REV. SEP 14, 2005 Page 1 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
Applications
• Telecommunications
• Data communications
• Wireless communications
• Servers
Benefits
• High efficiency – no heat sink required
• For output voltages ranging from 3.3 to 1.0 V, 40%
higher current capability at elevated temperatures
than most competitors' 20-25A quarter-bricks
• Extremely small footprint: 0.896” x 2.30” (2.06 in2),
40% smaller than conventional quarter-bricks
Features
• “G” option designates RoHS for all six substances;
Standard configurations are RoHS compliant with
Pb solder exemption 1
• Delivers up to 15 A (50 W)
• Industry-standard quarter-brick pinout
• Outputs available in 12.0, 8.0, 6.0, 5.0, 3.3, 2.5, 2.0,
1.8, 1.5, 1.2, and 1.0 V
• Available in through-hole and SMT packages
• Lowest profile in industry: 0.258” (6.55 mm)
• Lowest weight in industry: 0.53 oz (15 g)
• On-board input differential LC-filter
• Startup into pre-biased output
• No minimum load required
• Meets Basic Insulation requirements of EN60950
• Withstands 100 V input transient for 100 ms
• Fixed frequency operation
• Fully protected
• Remote output sense
• Positive or negative logic ON/OFF option
• Output voltage trim range: +10%/20% with
industry-standard trim equations (except 1.2 V and
1.0 V outputs with trim range ±10%)
• High reliability: MTBF = 3.4 million hours, calculated
per Telcordia TR-332, Method I Case 1
• UL60950 recognized in US and Canada and
DEMKO certified per IEC/EN60950
• Designed to meet Class B conducted emissions per
FCC and EN55022 when used with external filter
• All materials meet UL94, V-0 flammability rating
Description
The SemiQ™ Family of dc-dc converters provide a high efficiency single output in a size that is only 60% of
industry-standard quarter-bricks, while preserving the same pinout and functionality.
In high temperature environments, for output voltages ranging from 3.3 V to 1.0 V, the thermal performance of
SemiQ™ converters exceeds that of most competitors' 20-25 A quarter-bricks. This performance is accomplished
through the use of patent-pending circuit, packaging, and processing techniques to achieve ultra-high efficiency,
excellent thermal management, and a very low body profile.
Low body profile and the preclusion of heat sinks minimize airflow shadowing, thus enhancing cooling for
downstream devices. The use of 100% automation for assembly, coupled with advanced electronic circuits and
thermal design, results in a product with extremely high reliability.
Operating from a 36-75 V input, the SQ48 Series converters provide any standard output voltage from 12 V down
to 1.0 V. Outputs can be trimmed from –20% to +10% of the nominal output voltage (±10% for output voltages
1.2 V and 1.0 V), thus providing outstanding design flexibility.
With a standard pinout and trim equations, the SQ48 Series converters are perfect drop-in replacements for
existing quarter-brick designs. Inclusion of this converter in new designs can result in significant board space and
cost savings. In both cases the designer can expect reliability improvement over other available converters
because of the SQ48 Series’ optimized thermal efficiency.
1 The solder exemption is for customers choosing to use the exemptions for lead in solders for servers, storage and storage array systems, and
network infrastructure equipment for switching, signaling, transmission, and network management for telecommunications.
REV. SEP 14, 2005 Page 2 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
Electrical Specifications (common for all versions)
Conditions: TA = 25 ºC, Airflow = 300 LFM (1.5 m/s), Vin = 48 VDC, All output voltages, unless otherwise specified.
Parameter Notes Min Typ Max Units
Absolute Maximum Ratings
Input Voltage Continuous 0 80 VDC
Operating Ambient Temperature -40 85 °C
Storage Temperature -55 125 °C
Input Characteristics
Operating Input Voltage Range 36 48 75 VDC
Input Undervoltage Lockout Non-latching
Turn-on Threshold 33 34 35 VDC
Turn-off Threshold 31 32 33 VDC
Input Voltage Transient 100 ms 100 VDC
Isolation Characteristics
I/O Isolation 2000 VDC
Isolation Capacitance 1.0 - 3.3 V 160 pF
5.0 - 6.0 V 260 pF
8.0 - 12 V 230 pF
Isolation Resistance 10 M
Feature Characteristics
Switching Frequency 415 kHz
Industry-std. equations (1.5 - 12V) -20 +10 %
Output Voltage Trim Range1 Use trim equation on Page 4 (1.0 -1.2 V) -10 +10 %
Remote Sense Compensation1 Percent of VOUT(NOM) +10 %
Output Overvoltage Protection Non-latching (1.5 - 12 V) 117 122 127 %
Non-latching (1.0 - 1.2 V) 124 132 140 %
Auto-Restart Period Applies to all protection features 100 ms
Turn-On Time See Figs. F, G and H 4 ms
ON/OFF Control (Positive Logic)
Converter Off (logic low) -20 0.8 VDC
Converter On (logic high) 2.4 20 VDC
ON/OFF Control (Negative Logic)
Converter Off (logic high) 2.4 20 VDC
Converter On (logic low) -20 0.8 VDC
Additional Notes:
1 Vout can be increased up to 10% via the sense leads or up to 10% via the trim function. However, the total output voltage trim from all
sources should not exceed 10% of VOUT(NOM), in order to ensure specified operation of overvoltage protection circuitry.
REV. SEP 14, 2005 Page 3 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
Operations
Input and Output Impedance
These power converters have been designed to be
stable with no external capacitors when used in low
inductance input and output circuits.
In many applications, the inductance associated with
the distribution from the power source to the input of
the converter can affect the stability of the converter.
The addition of a 33 µF electrolytic capacitor with an
ESR < 1 across the input helps to ensure stability
of the converter. In many applications, the user has
to use decoupling capacitance at the load. The
power converter will exhibit stable operation with
external load capacitance up to 1000 µF on 12 V,
2,200 µF on 8.0 V, 10,000 µF on 5.0 – 6.0 V, and
15,000 µF on 3.3 – 1.0 V outputs.
Additionally, see the EMC section of this data sheet
for discussion of other external components which
may be required for control of conducted emissions.
ON/OFF (Pin 2)
The ON/OFF pin is used to turn the power converter
on or off remotely via a system signal. There are two
remote control options available, positive logic and
negative logic, with both referenced to Vin(-). A
typical connection is shown in Fig. A.
Rload
Vin
CONTROL
INPUT
Vin (+)
Vin (-)
ON/OFF
Vout (+)
Vout (-)
TRIM
SENSE (+)
SENSE (-)
(Top View)
Converter
SemiQTM Family
Fig. A: Circuit configuration for ON/OFF function.
The positive logic version turns on when the ON/OFF
pin is at a logic high and turns off when at a logic low.
The converter is on when the ON/OFF pin is left
open. See Electrical Specifications for logic high/low
definitions.
The negative logic version turns on when the pin is at
a logic low and turns off when the pin is at a logic
high. The ON/OFF pin can be hardwired directly to
Vin(-) to enable automatic power up of the converter
without the need of an external control signal.
The ON/OFF pin is internally pulled up to 5V through
a resistor. A properly debounced mechanical switch,
open collector transistor, or FET can be used to drive
the input of the ON/OFF pin. The device must be
capable of sinking up to 0.2 mA at a low level voltage
of ≤ 0.8 V. An external voltage source (±20 V
maximum) may be connected directly to the ON/OFF
input, in which case it must be capable of sourcing or
sinking up to 1 mA depending on the signal polarity.
See the Startup Information section for system timing
waveforms associated with use of the ON/OFF pin.
Remote Sense (Pins 5 and 7)
The remote sense feature of the converter
compensates for voltage drops occurring between the
output pins of the converter and the load. The
SENSE(-) (Pin 5) and SENSE(+) (Pin 7) pins should
be connected at the load or at the point where
regulation is required (see Fig. B).
100
10
Rw
Rw
Rload
Vin
Vin (+)
Vin (-)
ON/OFF
Vout (+)
Vout (-)
TRI
M
SENSE (+)
SENSE (-)
(Top View)
Converter
SemiQTM Family
Fig. B: Remote sense circuit configuration.
CAUTION
If remote sensing is not utilized, the SENSE(-) pin must be
connected to the Vout(-) pin (Pin 4), and the SENSE(+) pin
must be connected to the Vout(+) pin (Pin 8) to ensure the
converter will regulate at the specified output voltage. If these
connections are not made, the converter will deliver an output
voltage that is slightly higher than the specified data sheet
value.
Because the sense leads carry minimal current, large
traces on the end-user board are not required.
However, sense traces should be run side by side and
located close to a ground plane to minimize system
noise and ensure optimum performance.
When using the remote sense function, the
converter’s output overvoltage protection (OVP)
senses the voltage across Vout(+) and Vout(-), and
not across the sense lines, so the resistance (and
resulting voltage drop) between the output pins of the
converter and the load should be minimized to
prevent unwanted triggering of the OVP.
When utilizing the remote sense feature, care must be
taken not to exceed the maximum allowable output
power capability of the converter, which is equal to the
product of the nominal output voltage and the
allowable output current for the given conditions.
When using remote sense, the output voltage at the
converter can be increased by as much as 10%
above the nominal rating in order to maintain the
required voltage across the load. Therefore, the
REV. SEP 14, 2005 Page 4 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
designer must, if necessary, decrease the maximum
current (originally obtained from the derating curves)
by the same percentage to ensure the converter’s
actual output power remains at or below the
maximum allowable output power.
Output Voltage Adjust /TRIM (Pin 6)
The output voltage can be adjusted up 10% or down
20% for Vout 1.5 V, and ±10% for Vout = 1.2 V
relative to the rated output voltage by the addition of
an externally connected resistor. For output voltage
3.3 V, trim up to 10% is guaranteed only at
Vin 40 V, and it is marginal (8% to 10%) at
Vin = 36 V.
The TRIM pin should be left open if trimming is not
being used. To minimize noise pickup, a 0.1 µF
capacitor is connected internally between the TRIM
and SENSE(-) pins.
To increase the output voltage, refer to Fig. C. A trim
resistor, RT-INCR, should be connected between the
TRIM (Pin 6) and SENSE(+) (Pin 7), with a value of:
10.22
1.225∆
626∆)V5.11(100
RNOMO
INCRT −
−+
=−
− [k],
for 1.5 – 12 V.
7.2
∆
84.6
RINCRT −=− [k] (1.2 V)
9
∆
120
RINCRT −=− [k] (1.0 V)
where,
=−INCRTRRequired value of trim-up resistor [k]
=−NOMOVNominal value of output voltage [V]
100X
V
)V(V
∆
NOM- O
NOM-OREQ-O −
= [%]
=−REQOVDesired (trimmed) output voltage [V].
Rload
Vin
Vin (+)
Vin (-)
ON/OFF
Vout (+)
Vout (-)
TRIM
SENSE (+)
SENSE (-)
RT-INCR
(Top View)
Converter
SemiQTM Family
Fig. C: Configuration for increasing output voltage.
When trimming up, care must be taken not to exceed
the converter‘s maximum allowable output power. See
the previous section for a complete discussion of this
requirement.
To decrease the output voltage (Fig. D), a trim
resistor, RT-DECR, should be connected between the
TRIM (Pin 6) and SENSE(-) (Pin 5), with a value of:
10.22
∆
511
RDECRT −=− [k] (1.5 – 12 V)
15
∆
700
RDECRT −=− [k] (1.2 V)
17
|∆|
700
RDECRT −=− [k] (1.0 V)
where,
=
−DECRTRRequired value of trim-down resistor [k]
and
∆
is defined above.
Note:
The above equations for calculation of trim resistor values match
those typically used in conventional industry-standard quarter-
bricks and one-eighth bricks (except for 1.2 V and 1.0 V outputs).
Converters with output voltages 1.2 V and 1.0 V are
available with alternative trim feature to provide the
customers with the flexibility of second sourcing.
These converters have a “T” character in the part
number. The trim equations of “T” version of
converters and more information can be found in
Application Note 103.
Rload
Vin
Vin (+)
Vin (-)
ON/OFF
Vout (+)
Vout (-)
TRIM
SENSE (+)
SENSE (-)
RT-DECR
(Top View)
Converter
SemiQTM Family
Fig. D: Configuration for decreasing output voltage.
Trimming/sensing beyond 110% of the rated output
voltage is not an acceptable design practice, as this
condition could cause unwanted triggering of the
output overvoltage protection (OVP) circuit. The
designer should ensure that the difference between
the voltages across the converter’s output pins and its
sense pins does not exceed 10% of VOUT(NOM), or:
X NOM-O SENSESENSEOUTOUT 10%V)](V)([V)](V)([V ≤−−+
−
−
−
+
[V]
This equation is applicable for any condition of output
sensing and/or output trim.
REV. SEP 14, 2005 Page 5 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
Protection Features
Input Undervoltage Lockout
Input undervoltage lockout is standard with this
converter. The converter will shut down when the
input voltage drops below a pre-determined voltage.
The input voltage must be typically 34 V for the
converter to turn on. Once the converter has been
turned on, it will shut off when the input voltage drops
typically below 32 V. This feature is beneficial in
preventing deep discharging of batteries used in
telecom applications.
Output Overcurrent Protection (OCP)
The converter is protected against overcurrent or
short circuit conditions. Upon sensing an overcurrent
condition, the converter will switch to constant
current operation and thereby begin to reduce output
voltage. When the output voltage drops below 50%
of the nominal value of output voltage, the converter
will shut down (Fig. x.17).
Once the converter has shut down, it will attempt to
restart nominally every 100 ms with a typical 1-2%
duty cycle (Fig. x.18). The attempted restart will
continue indefinitely until the overload or short circuit
conditions are removed or the output voltage rises
above 50% of its nominal value.
Once the output current is brought back into its
specified range, the converter automatically exits the
hiccup mode and continues normal operation.
Output Overvoltage Protection (OVP)
The converter will shut down if the output voltage
across Vout(+) (Pin 8) and Vout(-) (Pin 4) exceeds
the threshold of the OVP circuitry. The OVP circuitry
contains its own reference, independent of the output
voltage regulation loop. Once the converter has shut
down, it will attempt to restart every 100 ms until the
OVP condition is removed.
Overtemperature Protection (OTP)
The converter will shut down under an
overtemperature condition to protect itself from
overheating caused by operation outside the thermal
derating curves, or operation in abnormal conditions
such as system fan failure. After the converter has
cooled to a safe operating temperature, it will
automatically restart.
Safety Requirements
The converters meet North American and
International safety regulatory requirements per
UL60950 and EN60950. Basic Insulation is provided
between input and output.
To comply with safety agencies’ requirements, an
input line fuse must be used external to the converter.
The Table below provides the recommended fuse
rating for use with this family of products.
Output Voltage Fuse Rating
3.3 V 4 A
12 - 5.0 V, 2.5 V 3 A
2.0 - 1.2 V 2 A
All SQ converters are UL approved for a maximum
fuse rating of 15 Amps. To protect a group of
converters with a single fuse, the rating can be
increased from the recommended values above.
Electromagnetic Compatibility (EMC)
EMC requirements must be met at the end-product
system level, as no specific standards dedicated to
EMC characteristics of board mounted component dc-
dc converters exist. However, Power-One tests its
converters to several system level standards, primary
of which is the more stringent EN55022, Information
technology equipment - Radio disturbance
characteristics - Limits and methods of measurement.
An effective internal LC differential filter significantly
reduces input reflected ripple current, and improves
EMC.
With the addition of a simple external filter (see
Application Note 100), all versions of the SQ48 Series
converters pass the requirements of Class B
conducted emissions per EN55022 and FCC
requirements. Please contact Power-One Applications
Engineering for details of this testing.
Characterization
General Information
The converter has been characterized for many
operational aspects, to include thermal derating
(maximum load current as a function of ambient
temperature and airflow) for vertical and horizontal
mounting, efficiency, startup and shutdown
parameters, output ripple and noise, transient
response to load step-change, overload, and short
circuit.
The figures are numbered as Fig. x.y, where x
indicates the different output voltages, and y
associates with specific plots (y = 1 for the vertical
thermal derating, …). For example, Fig. x.1 will refer
to the vertical thermal derating for all the output
voltages in general.
The following pages contain specific plots or
waveforms associated with the converter. Additional
comments for specific data are provided below.
REV. SEP 14, 2005 Page 6 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
Test Conditions
All data presented were taken with the converter
soldered to a test board, specifically a 0.060” thick
printed wiring board (PWB) with four layers. The top
and bottom layers were not metalized. The two inner
layers, comprised of two-ounce copper, were used to
provide traces for connectivity to the converter.
The lack of metalization on the outer layers as well
as the limited thermal connection ensured that heat
transfer from the converter to the PWB was
minimized. This provides a worst-case but consistent
scenario for thermal derating purposes.
All measurements requiring airflow were made in the
vertical and horizontal wind tunnel using Infrared (IR)
thermography and thermocouples for thermometry.
Ensuring components on the converter do not
exceed their ratings is important to maintaining high
reliability. If one anticipates operating the converter
at or close to the maximum loads specified in the
derating curves, it is prudent to check actual
operating temperatures in the application.
Thermographic imaging is preferable; if this capability
is not available, then thermocouples may be used.
The use of AWG #40 gauge thermocouples is
recommended to ensure measurement accuracy.
Careful routing of the thermocouple leads will further
minimize measurement error. Refer to Fig. E for the
optimum measuring thermocouple location.
Fig. E: Location of the thermocouple for thermal testing.
Thermal Derating
Load current vs. ambient temperature and airflow
rates are given in Fig. x.1 to Fig. x.4 for through-hole
and surface-mount versions. Ambient temperature
was varied between 25 °C and 85 °C, with airflow
rates from 30 to 500 LFM (0.15 to 2.5 m/s), and
vertical and horizontal converter mounting.
For each set of conditions, the maximum load current
was defined as the lowest of:
(i) The output current at which any FET junction
temperature does not exceed a maximum specified
temperature (120°C) as indicated by the
thermographic image, or
(ii) The nominal rating of the converter (4 A on 12 V,
5.3 A on 8.0 V, 8 A on 6.0 V, 10 A on 5.0 V, and 15 A
on 3.3 – 1.0 V)).
During normal operation, derating curves with
maximum FET temperature less or equal to 120 °C
should not be exceeded. Temperature on the PCB at
thermocouple location shown in Fig. E should not
exceed 118 °C in order to operate inside the derating
curves.
Efficiency
Fig. x.5 shows the efficiency vs. load current plot for
ambient temperature of 25 ºC, airflow rate of 300 LFM
(1.5 m/s) with vertical mounting and input voltages of
36 V, 48 V and 72 V. Also, a plot of efficiency vs. load
current, as a function of ambient temperature with
Vin = 48 V, airflow rate of 200 LFM (1 m/s) with
vertical mounting is shown in Fig. x.6.
Power Dissipation
Fig. x.7 shows the power dissipation vs. load current
plot for Ta = 25 ºC, airflow rate of 300 LFM (1.5 m/s)
with vertical mounting and input voltages of 36 V, 48
V and 72 V. Also, a plot of power dissipation vs. load
current, as a function of ambient temperature with
Vin = 48 V, airflow rate of 200 LFM (1 m/s) with
vertical mounting is shown in Fig. x.8.
Startup
Output voltage waveforms, during the turn-on
transient using the ON/OFF pin for full rated load
currents (resistive load) are shown without and with
external load capacitance in Fig. x.9 and Fig. x.10,
respectively.
Ripple and Noise
Fig. x.13 shows the output voltage ripple waveform,
measured at full rated load current with a 10 µF
tantalum and 1 µF ceramic capacitor across the
output. Note that all output voltage waveforms are
measured across a 1 µF ceramic capacitor.
The input reflected ripple current waveforms are
obtained using the test setup shown in Fig x.14. The
corresponding waveforms are shown in Fig. x.15 and
Fig. x.16.
REV. SEP 14, 2005 Page 7 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
Startup Information (using negative ON/OFF)
Scenario #1: Initial Startup From Bulk Supply
ON/OFF function enabled, converter started via application
of VIN. See Figure F.
Time Comments
t0 ON/OFF pin is ON; system front end power is
toggled on, VIN to converter begins to rise.
t1 V
IN crosses Undervoltage Lockout protection
circuit threshold; converter enabled.
t2 Converter begins to respond to turn-on
command (converter turn-on delay).
t3 Converter VOUT reaches 100% of nominal value.
For this example, the total converter startup time (t3- t1) is
typically 4 ms.
Scenario #2: Initial Startup Using ON/OFF Pin
With VIN previously powered, converter started via
ON/OFF pin. See Figure G.
Time Comments
t0 V
INPUT at nominal value.
t1 Arbitrary time when ON/OFF pin is enabled
(converter enabled).
t2 End of converter turn-on delay.
t3 Converter VOUT reaches 100% of nominal value.
For this example, the total converter startup time (t3- t1) is
typically 4 ms.
Scenario #3: Turn-off and Restart Using ON/OFF Pin
With VIN previously powered, converter is disabled and
then enabled via ON/OFF pin. See Figure H.
Time Comments
t0 V
IN and VOUT are at nominal values; ON/OFF pin
ON.
t1 ON/OFF pin arbitrarily disabled; converter output
falls to zero; turn-on inhibit delay period (100 ms
typical) is initiated, and ON/OFF pin action is
internally inhibited.
t2 ON/OFF pin is externally re-enabled.
If (t2- t1) ≤ 100 ms, external action of
ON/OFF pin is locked out by startup inhibit
timer.
If (t2- t1) > 100 ms, ON/OFF pin action is
internally enabled.
t3 Turn-on inhibit delay period ends. If ON/OFF pin
is ON, converter begins turn-on; if off, converter
awaits ON/OFF pin ON signal; see Figure G.
t4 End of converter turn-on delay.
t5 Converter VOUT reaches 100% of nominal value.
For the condition, (t2- t1) ≤ 100 ms, the total converter
startup time (t5- t2) is typically 104 ms. For (t2- t1) > 100 ms,
startup will be typically 4 ms after release of ON/OFF pin.
VIN
ON/OFF
STATE
VOUT
t
t0t1t2t3
ON
OFF
Fig. F: Startup scenario #1.
ON/OFF
STATE
VOUT
t0t1t2t3
ON
OFF
VIN
t
Fig. G: Startup scenario #2.
ON/OFF
STATE OFF
ON
VOUT
t0t2t1t5
VIN
t
t4t3
100 ms
Fig. H: Startup scenario #3.
REV. SEP 14, 2005 Page 8 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
Electrical Specifications: SQ48T/S04120 (12 Volt Out)
Conditions: TA = 25 ºC, Airflow = 300 LFM (1.5 m/s), Vin = 48 VDC, Vout = 12 VDC, unless otherwise specified.
Parameter Notes Min Typ Max Units
Input Characteristics
Maximum Input Current 4 ADC, 12 VDC Out @ 36 VDC In 1.53 ADC
Input Stand-by Current Vin = 48 V, converter disabled 3 mADC
Input No Load Current (0 load on the output) Vin = 48 V, converter enabled 45 mADC
Input Reflected-Ripple Current 25 MHz bandwidth 6 mAPK-PK
Input Voltage Ripple Rejection 120 Hz TBD dB
Output Characteristics
Output Voltage Set Point (no load) 11.880 12.000 12.120 VDC
Output Regulation
Over Line ±4 ±5 mV
Over Load ±4 ±5 mV
Output Voltage Range Over line, load and temperature1 11.820 12.180 VDC
Output Ripple and Noise - 25 MHz
bandwidth
Full load + 10 µF tantalum + 1 µF
ceramic 80 120 mVPK-PK
External Load Capacitance Plus full load (resistive) 1,000 µF
Output Current Range 0 4 ADC
Current Limit Inception Non-latching 4.5 5 5.5 ADC
Peak Short-Circuit Current Non-latching, Short =10 m. 7.5 10 A
RMS Short-Circuit Current Non-latching 4 Arms
Dynamic Response
Load Change 25% of Iout Max, di/dt = 0.1 A/µs Co = 1 µF ceramic 200 mV
di/dt = 5 A/µs Co = 47 µF tantalum + 1 µF ceramic 200 mV
Settling Time to 1% 400 µs
Efficiency
100% Load 87.0 %
50% Load 87.0 %
1 -40 ºC to 85 ºC.
Ambient Temperature [°C]
20 30 40 50 60 70 80 90
Load Current [Adc]
0
1
2
3
4
5
500 LFM (2.5 m/s)
400 LFM (2.0 m/s)
300 LFM (1.5 m/s)
200 LFM (1.0 m/s)
100 LFM (0.5 m/s)
30 LFM (0.15 m/s)
Fig. 12V.1: Available load current vs. ambient air
temperature and airflow rates for SQ48T04120 converter
with D height pins mounted vertically with Vin = 48 V, air
flowing from pin 3 to pin 1, and maximum FET
temperature ≤ 120 °C.
Ambient Temperature [°C]
20 30 40 50 60 70 80 90
Load Current [Adc]
0
1
2
3
4
5
500 LFM (2.5 m/s)
400 LFM (2.0 m/s)
300 LFM (1.5 m/s)
200 LFM (1.0 m/s)
100 LFM (0.5 m/s)
30 LFM (0.15 m/s)
Fig. 12V.2: Available load current vs. ambient air
temperature and airflow rates for SQ48T04120 converter
with D height pins mounted horizontally with Vin = 48 V,
air flowing from pin 3 to pin 1, and maximum FET
temperature ≤ 120 °C.
REV. SEP 14, 2005 Page 9 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
SQ48T/S04120 (12 Volt Out)
Ambient Temperature [°C]
20 30 40 50 60 70 80 90
Load Current [Adc]
0
1
2
3
4
5
500 LFM (2.5 m/s)
400 LFM (2.0 m/s)
300 LFM (1.5 m/s)
200 LFM (1.0 m/s)
100 LFM (0.5 m/s)
30 LFM (0.15 m/s)
Fig. 12V.3: Available load current vs. ambient air
temperature and airflow rates for SQ48S04120 converter
mounted vertically with Vin = 48 V, air flowing from pin 3
to pin 1, and maximum FET temperature ≤ 120 °C.
Load Current [Adc]
012345
Efficiency
0.65
0.70
0.75
0.80
0.85
0.90
0.95
72 V
48 V
36 V
Fig. 12V.5: Efficiency vs. load current and input voltage for
SQ48T/S04120 converter mounted vertically with air
flowing from pin 3 to pin 1 at a rate of 300 LFM (1.5 m/s)
and Ta = 25 °C.
Ambient Temperature [°C]
20 30 40 50 60 70 80 90
Load Current [Adc]
0
1
2
3
4
5
500 LFM (2.5 m/s)
400 LFM (2.0 m/s)
300 LFM (1.5 m/s)
200 LFM (1.0 m/s)
100 LFM (0.5 m/s)
30 LFM (0.15 m/s)
Fig. 12V.4: Available load current vs. ambient air
temperature and airflow rates for SQ48S04120 converter
mounted horizontally with Vin = 48 V, air flowing from pin
3 to pin 1, and maximum FET temperature ≤ 120 °C.
Load Current [Adc]
012345
Efficiency
0.65
0.70
0.75
0.80
0.85
0.90
0.95
70 C
55 C
40 C
Fig. 12V.6: Efficiency vs. load current and ambient
temperature for SQ48T/S04120 converter mounted
vertically with Vin = 48 V and air flowing from pin 3 to pin
1 at a rate of 200 LFM (1.0 m/s).
REV. SEP 14, 2005 Page 10 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
SQ48T/S04120 (12 Volt Out)
Load Current [Adc]
012345
P
ower
Di
ss
i
pa
ti
on
[W]
0.00
2.00
4.00
6.00
8.00
10.00
72 V
48 V
36 V
Fig. 12V.7: Power dissipation vs. load current and
input voltage for SQ48T/S04120 converter mounted
vertically with air flowing from pin 3 to pin 1 at a rate of
300 LFM (1.5 m/s) and Ta = 25 °C.
Fig. 12V.9: Turn-on transient at full rated load current
(resistive) with no output capacitor at Vin = 48 V,
triggered via ON/OFF pin. Top trace: ON/OFF signal
(5 V/div.). Bottom trace: output voltage (5 V/div.). Time
scale: 1 ms/div.
Load Current [Adc]
012345
P
ower
Di
ss
i
pa
ti
on
[W]
0.00
2.00
4.00
6.00
8.00
10.00
70 C
55 C
40 C
Fig. 12V.8: Power dissipation vs. load current and
ambient temperature for SQ48T/S04120 converter
mounted vertically with Vin = 48 V and air flowing from
pin 3 to pin 1 at a rate of 200 LFM (1.0 m/s).
Fig. 12V.10: Turn-on transient at full rated load current
(resistive) plus 1,000 µF at Vin = 48 V, triggered via
ON/OFF pin. Top trace: ON/OFF signal (5 V/div.).
Bottom trace: output voltage (5 V/div.). Time scale:
2 ms/div.
REV. SEP 14, 2005 Page 11 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
SQ48T/S04120 (12 Volt Out)
Fig. 12V.11: Output voltage response to load current
step-change (1 A – 2 A – 1 A) at Vin = 48 V. Top trace:
output voltage (200 mV/div.). Bottom trace: load current
(1 A/div.). Current slew rate: 0.1 A/µs. Co = 1 µF
ceramic. Time scale: 0.5 ms/div.
Fig. 12V.13: Output voltage ripple (50 mV/div.) at full
rated load current into a resistive load with Co = 10 µF
tantalum + 1 µF ceramic and Vin = 48 V. Time scale:
1 µs/div.
Fig. 12V.12: Output voltage response to load current
step-change (1 A – 2 A – 1 A) at Vin = 48 V. Top trace:
output voltage (200 mV/div.). Bottom trace: load current
(1 A/div.). Current slew rate: 5 A/µs. Co = 47 µF
tantalum + 1 µF ceramic. Time scale: 0.5 ms/div.
Vout
Vsource
iSiC
1 µF
ceramic
capacitor
10 µH
source
inductance SemiQTM Family
DC-DC
Converter
33 µF
ESR <1
electrolytic
capacitor
Ω
Fig. 12V.14: Test Setup for measuring input reflected
ripple currents, ic and is.
REV. SEP 14, 2005 Page 12 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
SQ48T/S04120 (12 Volt Out)
Fig. 12V.15: Input reflected ripple current, ic
(100 mA/div.), measured at input terminals at full rated
load current and Vin = 48 V. Refer to Fig. 12V.14 for test
setup. Time scale: 1 µs/div.
14
6
15
Iout [Adc]
Vout [Vdc]
0
0
10
5
23 5
Fig. 12V.17: Output voltage vs. load current showing
current limit point and converter shutdown point. Input
voltage has almost no effect on current limit
characteristic.
Fig. 12V.16: Input reflected ripple current, is
(10 mA/div.), measured through 10 µH at the source at
full rated load current and Vin = 48 V. Refer to
Fig. 12V.14 for test setup. Time scale: 1 µs/div.
Fig. 12V.18: Load current (top trace, 5 A/div.,
20 ms/div.) into a 10 m short circuit during restart, at
Vin = 48 V. Bottom trace (5 A/div., 1 ms/div.) is an
expansion of the on-time portion of the top trace.
REV. SEP 14, 2005 Page 13 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
Electrical Specifications: SQ48T/S05080 (8.0 Volt Out)
Conditions: TA = 25 ºC, Airflow = 300 LFM (1.5 m/s), Vin = 48 VDC, Vout = 8.0 VDC, unless otherwise specified.
Parameter Notes Min Typ Max Units
Input Characteristics
Maximum Input Current 5.3 ADC, 8.0 VDC Out @ 36 VDC In 1.38 ADC
Input Stand-by Current Vin = 48 V, converter disabled 3 mADC
Input No Load Current (0 load on the output) Vin = 48 V, converter enabled 33 mADC
Input Reflected-Ripple Current 25 MHz bandwidth 6 mAPK-PK
Input Voltage Ripple Rejection 120 Hz TBD dB
Output Characteristics
Output Voltage Set Point (no load) 7.920 8.000 8.080 VDC
Output Regulation
Over Line ±4 ±10 mV
Over Load ±4 ±10 mV
Output Voltage Range Over line, load and temperature1 7.880 8.120 VDC
Output Ripple and Noise - 25 MHz
bandwidth
Full load + 10 µF tantalum + 1 µF
ceramic 70 100 mVPK-PK
External Load Capacitance Plus full load (resistive) 2,200 µF
Output Current Range 0 5.3 ADC
Current Limit Inception Non-latching 5.75 6.25 6.75 ADC
Peak Short-Circuit Current Non-latching, Short =10 m. 10 12 A
RMS Short-Circuit Current Non-latching 4 Arms
Dynamic Response
Load Change 25% of Iout Max, di/dt = 0.1 A/µs Co = 1 µF ceramic 160 mV
di/dt = 5 A/µs Co = 94 µF tantalum + 1 µF ceramic 160 mV
Settling Time to 1% 400 µs
Efficiency
100% Load 85.5 %
50% Load 87.0 %
1 -40 ºC to 85 ºC.
Ambient Temperature [°C]
20 30 40 50 60 70 80 90
Load Current [Adc]
0
1
2
3
4
5
6
500 LFM (2.5 m/s)
400 LFM (2.0 m/s)
300 LFM (1.5 m/s)
200 LFM (1.0 m/s)
100 LFM (0.5 m/s)
30 LFM (0.15 m/s)
Fig. 8.0V.1: Available load current vs. ambient air
temperature and airflow rates for SQ48T05080 converter
with D height pins mounted vertically with Vin = 48 V, air
flowing from pin 3 to pin 1, and maximum FET
temperature ≤ 120 °C.
Ambient Temperature [°C]
20 30 40 50 60 70 80 90
Load Current [Adc]
0
1
2
3
4
5
6
500 LFM (2.5 m/s)
400 LFM (2.0 m/s)
300 LFM (1.5 m/s)
200 LFM (1.0 m/s)
100 LFM (0.5 m/s)
30 LFM (0.15 m/s)
Fig. 8.0V.2: Available load current vs. ambient air
temperature and airflow rates for SQ48T05080 converter
with D height pins mounted horizontally with Vin = 48 V,
air flowing from pin 3 to pin 1, and maximum FET
temperature ≤ 120 °C.
REV. SEP 14, 2005 Page 14 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
SQ48T/S05080 (8.0 Volt Out)
Ambient Temperature [°C]
20 30 40 50 60 70 80 90
Load Current [Adc]
0
1
2
3
4
5
6
500 LFM (2.5 m/s)
400 LFM (2.0 m/s)
300 LFM (1.5 m/s)
200 LFM (1.0 m/s)
100 LFM (0.5 m/s)
30 LFM (0.15 m/s)
Fig. 8.0V.3: Available load current vs. ambient air
temperature and airflow rates for SQ48S05080 converter
mounted vertically with Vin = 48 V, air flowing from pin 3
to pin 1, and maximum FET temperature ≤ 120 °C.
Load Current [Adc]
0123456
Efficiency
0.65
0.70
0.75
0.80
0.85
0.90
0.95
72 V
48 V
36 V
Fig. 8.0V.5: Efficiency vs. load current and input voltage
for SQ48T/S05080 converter mounted vertically with air
flowing from pin 3 to pin 1 at a rate of 300 LFM (1.5 m/s)
and Ta = 25 °C.
Ambient Temperature [°C]
20 30 40 50 60 70 80 90
Load Current [Adc]
0
1
2
3
4
5
6
500 LFM (2.5 m/s)
400 LFM (2.0 m/s)
300 LFM (1.5 m/s)
200 LFM (1.0 m/s)
100 LFM (0.5 m/s)
30 LFM (0.15 m/s)
Fig. 8.0V.4: Available load current vs. ambient air
temperature and airflow rates for SQ48S05080 converter
mounted horizontally with Vin = 48 V, air flowing from pin
3 to pin 1, and maximum FET temperature ≤ 120 °C.
Load Current [Adc]
0123456
Efficiency
0.65
0.70
0.75
0.80
0.85
0.90
0.95
70 C
55 C
40 C
Fig. 8.0V.6: Efficiency vs. load current and ambient
temperature for SQ48T/S05080 converter mounted
vertically with Vin = 48 V and air flowing from pin 3 to pin
1 at a rate of 200 LFM (1.0 m/s).
REV. SEP 14, 2005 Page 15 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
SQ48T/S05080 (8.0 Volt Out)
Load Current [Adc]
0123456
P
ower
Di
ss
i
pa
ti
on
[W]
0.00
2.00
4.00
6.00
8.00
10.00
72 V
48 V
36 V
Fig. 8.0V.7: Power dissipation vs. load current and
input voltage for SQ48T/S05080 converter mounted
vertically with air flowing from pin 3 to pin 1 at a rate of
300 LFM (1.5 m/s) and Ta = 25 °C.
Fig. 8.0V.9: Turn-on transient at full rated load current
(resistive) with no output capacitor at Vin = 48 V,
triggered via ON/OFF pin. Top trace: ON/OFF signal
(5 V/div.). Bottom trace: output voltage (2 V/div.). Time
scale: 1 ms/div.
Load Current [Adc]
0123456
P
ower
Di
ss
i
pa
ti
on
[W]
0.00
2.00
4.00
6.00
8.00
10.00
70 C
55 C
40 C
Fig. 8.0V.8: Power dissipation vs. load current and
ambient temperature for SQ48T/S05080 converter
mounted vertically with Vin = 48 V and air flowing from
pin 3 to pin 1 at a rate of 200 LFM (1.0 m/s).
Fig. 8.0V.10: Turn-on transient at full rated load
current (resistive) plus 2,200 µF at Vin = 48 V,
triggered via ON/OFF pin. Top trace: ON/OFF signal
(5 V/div.). Bottom trace: output voltage (2 V/div.). Time
scale: 2 ms/div.
REV. SEP 14, 2005 Page 16 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
SQ48T/S05080 (8.0 Volt Out)
Fig. 8.0V.11: Output voltage response to load current
step-change (1.325 A – 2.65 A – 1.325 A) at Vin = 48 V.
Top trace: output voltage (200 mV/div.). Bottom trace:
load current (1 A/div.). Current slew rate: 0.1 A/µs.
Co = 1 µF ceramic. Time scale: 0.5 ms/div.
Fig. 8.0V.13: Output voltage ripple (50 mV/div.) at full
rated load current into a resistive load with Co = 10 µF
tantalum + 1 µF ceramic and Vin = 48 V. Time scale:
1 µs/div.
Fig. 8.0V.12: Output voltage response to load current
step-change (1.325 A – 2.65 A – 1.325 A) at Vin = 48 V.
Top trace: output voltage (200 mV/div.). Bottom trace:
load current (1 A/div.). Current slew rate: 5 A/µs.
Co = 94 µF tantalum + 1 µF ceramic. Time scale:
0.5 ms/div.
Vout
Vsource
iSiC
1 µF
ceramic
capacitor
10 µH
source
inductance SemiQTM Family
DC-DC
Converter
33 µF
ESR <1
electrolytic
capacitor
Ω
Fig. 8.0V.14: Test Setup for measuring input reflected
ripple currents, ic and is.
REV. SEP 14, 2005 Page 17 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
SQ48T/S05080 (8.0 Volt Out)
Fig. 8.0V.15: Input reflected ripple current, ic
(100 mA/div.), measured at input terminals at full rated
load current and Vin = 48 V. Refer to Fig. 8.0V.14 for
test setup. Time scale: 1 µs/div.
28
Iout [Adc]
Vout [Vdc]
0
0
46
12
8
4
Fig. 8.0V.17: Output voltage vs. load current showing
current limit point and converter shutdown point. Input
voltage has almost no effect on current limit
characteristic.
Fig. 8.0V.16: Input reflected ripple current, is
(10 mA/div.), measured through 10 µH at the source at
full rated load current and Vin = 48 V. Refer to
Fig. 8.0V.14 for test setup. Time scale: 1 µs/div.
Fig. 8.0V.18: Load current (top trace, 5 A/div.,
20 ms/div.) into a 10 m short circuit during restart, at
Vin = 48 V. Bottom trace (5 A/div., 1 ms/div.) is an
expansion of the on-time portion of the top trace.
REV. SEP 14, 2005 Page 18 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
Electrical Specifications: SQ48T/S08060 (6.0 Volt Out)
Conditions: TA = 25 ºC, Airflow = 300 LFM (1.5 m/s), Vin = 48 VDC, Vout = 6.0 VDC, unless otherwise specified.
Parameter Notes Min Typ Max Units
Input Characteristics
Maximum Input Current 8 ADC, 6.0 VDC Out @ 36 VDC In 1.5 ADC
Input Stand-by Current Vin = 48 V, converter disabled 3 mADC
Input No Load Current (0 load on the output) Vin = 48 V, converter enabled 45 mADC
Input Reflected-Ripple Current 25 MHz bandwidth 6 mAPK-PK
Input Voltage Ripple Rejection 120 Hz TBD dB
Output Characteristics
Output Voltage Set Point (no load) 5.940 6.000 6.060 VDC
Output Regulation
Over Line ±2 ±5 mV
Over Load ±2 ±5 mV
Output Voltage Range Over line, load and temperature1 5.910 6.090 VDC
Output Ripple and Noise - 25 MHz
bandwidth
Full load + 10 µF tantalum + 1 µF
ceramic 45 60 mVPK-PK
External Load Capacitance Plus full load (resistive) 10,000 µF
Output Current Range 0 8 ADC
Current Limit Inception Non-latching 8.4 10 11.5 ADC
Peak Short-Circuit Current Non-latching, Short =10 m. 15 25 A
RMS Short-Circuit Current Non-latching 5.3 Arms
Dynamic Response
Load Change 25% of Iout Max, di/dt = 0.1 A/µs Co = 1 µF ceramic 100 mV
di/dt = 5 A/µs Co = 450 µF tantalum + 1 µF ceramic 80 mV
Settling Time to 1% 200 µs
Efficiency
100% Load 89.0 %
50% Load 89.0 %
1 -40 ºC to 85 ºC.
Ambient Temperature [°C]
20 30 40 50 60 70 80 90
Load Current [Adc]
0
2
4
6
8
10
500 LFM (2.5 m/s)
400 LFM (2.0 m/s)
300 LFM (1.5 m/s)
200 LFM (1.0 m/s)
100 LFM (0.5 m/s)
30 LFM (0.15 m/s)
Fig. 6.0V.1: Available load current vs. ambient air
temperature and airflow rates for SQ48T08060 converter
with D height pins mounted vertically with Vin = 48 V, air
flowing from pin 3 to pin 1, and maximum FET
temperature ≤ 120 °C.
Ambient Temperature [°C]
20 30 40 50 60 70 80 90
Load Current [Adc]
0
2
4
6
8
10
500 LFM (2.5 m/s)
400 LFM (2.0 m/s)
300 LFM (1.5 m/s)
200 LFM (1.0 m/s)
100 LFM (0.5 m/s)
30 LFM (0.15 m/s)
Fig. 6.0V.2: Available load current vs. ambient air
temperature and airflow rates for SQ48T08060 converter
with D height pins mounted horizontally with Vin = 48 V,
air flowing from pin 3 to pin 1, and maximum FET
temperature ≤ 120 °C.
REV. SEP 14, 2005 Page 19 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
SQ48T/S08060 (6.0 Volt Out)
Ambient Temperature [°C]
20 30 40 50 60 70 80 90
Load Current [Adc]
0
2
4
6
8
10
500 LFM (2.5 m/s)
400 LFM (2.0 m/s)
300 LFM (1.5 m/s)
200 LFM (1.0 m/s)
100 LFM (0.5 m/s)
30 LFM (0.15 m/s)
Fig. 6.0V.3: Available load current vs. ambient air
temperature and airflow rates for SQ48S08060 converter
mounted vertically with Vin = 48 V, air flowing from pin 3
to pin 1, and maximum FET temperature ≤ 120 °C.
Load Current [Adc]
0246810
Efficiency
0.65
0.70
0.75
0.80
0.85
0.90
0.95
72 V
48 V
36 V
Fig. 6.0V.5: Efficiency vs. load current and input voltage for
SQ48T/S08060 converter mounted vertically with air
flowing from pin 3 to pin 1 at a rate of 300 LFM (1.5 m/s)
and Ta = 25 °C.
Ambient Temperature [°C]
20 30 40 50 60 70 80 90
Load Current [Adc]
0
2
4
6
8
10
500 LFM (2.5 m/s)
400 LFM (2.0 m/s)
300 LFM (1.5 m/s)
200 LFM (1.0 m/s)
100 LFM (0.5 m/s)
30 LFM (0.15 m/s)
Fig. 6.0V.4: Available load current vs. ambient air
temperature and airflow rates for SQ48S08060 converter
mounted horizontally with Vin = 48 V, air flowing from pin
3 to pin 1, and maximum FET temperature ≤ 120 °C.
Load Current [Adc]
0246810
Efficiency
0.65
0.70
0.75
0.80
0.85
0.90
0.95
70 C
55 C
40 C
Fig. 6.0V.6: Efficiency vs. load current and ambient
temperature for SQ48T/S08060 converter mounted
vertically with Vin = 48 V and air flowing from pin 3 to pin
1 at a rate of 200 LFM (1.0 m/s).
REV. SEP 14, 2005 Page 20 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
SQ48T/S08060 (6.0 Volt Out)
Load Current [Adc]
0246810
Power Dissipation [W]
0.00
2.00
4.00
6.00
8.00
72 V
48 V
36 V
Fig. 6.0V.7: Power dissipation vs. load current and
input voltage for SQ48T/S08060 converter mounted
vertically with air flowing from pin 3 to pin 1 at a rate of
300 LFM (1.5 m/s) and Ta = 25 °C.
Fig. 6.0V.9: Turn-on transient at full rated load current
(resistive) with no output capacitor at Vin = 48 V,
triggered via ON/OFF pin. Top trace: ON/OFF signal
(5 V/div.). Bottom trace: output voltage (2 V/div.). Time
scale: 2 ms/div.
Load Current [Adc]
0246810
Power Dissipation [W]
0.00
2.00
4.00
6.00
8.00
70 C
55 C
40 C
Fig. 6.0V.8: Power dissipation vs. load current and
ambient temperature for SQ48T/S08060 converter
mounted vertically with Vin = 48 V and air flowing from
pin 3 to pin 1 at a rate of 200 LFM (1.0 m/s).
Fig. 6.0V.10: Turn-on transient at full rated load
current (resistive) plus 10,000 µF at Vin = 48 V,
triggered via ON/OFF pin. Top trace: ON/OFF signal
(5 V/div.). Bottom trace: output voltage (2 V/div.). Time
scale: 5 ms/div.
REV. SEP 14, 2005 Page 21 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
SQ48T/S08060 (6.0 Volt Out)
Fig. 6.0V.11: Output voltage response to load current
step-change (2 A – 4 A – 2 A) at Vin = 48 V. Top trace:
output voltage (100 mV/div.). Bottom trace: load current
(2 A/div.). Current slew rate: 0.1 A/µs. Co = 1 µF
ceramic. Time scale: 0.2 ms/div.
Fig. 6.0V.13: Output voltage ripple (50 mV/div.) at full
rated load current into a resistive load with Co = 10 µF
tantalum + 1 µF ceramic and Vin = 48 V. Time scale:
1 µs/div.
Fig. 6.0V.12: Output voltage response to load current
step-change (2 A – 4 A – 2 A) at Vin = 48 V. Top trace:
output voltage (100 mV/div.). Bottom trace: load current
(2 A/div.). Current slew rate: 5 A/µs. Co = 450 µF
tantalum + 1 µF ceramic. Time scale: 0.2 ms/div.
Vout
Vsource
iSiC
1 µF
ceramic
capacitor
10 µH
source
inductance SemiQTM Family
DC-DC
Converter
33 µF
ESR <1
electrolytic
capacitor
Ω
Fig. 6.0V.14: Test Setup for measuring input reflected
ripple currents, ic and is.
REV. SEP 14, 2005 Page 22 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
SQ48T/S08060 (6.0 Volt Out)
Fig. 6.0V.15: Input reflected ripple current, ic
(100 mA/div.), measured at input terminals at full rated
load current and Vin = 48 V. Refer to Fig. 6.0V.14 for
test setup. Time scale: 1 µs/div.
312
8
Iout [Adc]
Vout [Vdc]
0
0
4
2
69
6
Fig. 6.0V.17: Output voltage vs. load current showing
current limit point and converter shutdown point. Input
voltage has almost no effect on current limit
characteristic.
Fig. 6.0V.16: Input reflected ripple current, is
(10 mA/div.), measured through 10 µH at the source at
full rated load current and Vin = 48 V. Refer to
Fig. 6.0V.14 for test setup. Time scale: 1 µs/div.
Fig. 6.0V.18: Load current (top trace, 10 A/div.,
20 ms/div.) into a 10 m short circuit during restart, at
Vin = 48 V. Bottom trace (10 A/div., 1 ms/div.) is an
expansion of the on-time portion of the top trace.
REV. SEP 14, 2005 Page 23 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
Electrical Specifications: SQ48T/S10050 (5.0 Volt Out)
Conditions: TA = 25 ºC, Airflow = 300 LFM (1.5 m/s), Vin = 48 VDC, Vout = 5.0 VDC, unless otherwise specified.
Parameter Notes Min Typ Max Units
Input Characteristics
Maximum Input Current 10 ADC, 5.0 VDC Out @ 36 VDC In 1.65 ADC
Input Stand-by Current Vin = 48 V, converter disabled 2.6 mADC
Input No Load Current (0 load on the output) Vin = 48 V, converter enabled 40 mADC
Input Reflected-Ripple Current 25 MHz bandwidth 6 mAPK-PK
Input Voltage Ripple Rejection 120 Hz TBD dB
Output Characteristics
Output Voltage Set Point (no load) 4.950 5.000 5.050 VDC
Output Regulation
Over Line ±2 ±5 mV
Over Load ±2 ±5 mV
Output Voltage Range Over line, load and temperature1 4.925 5.075 VDC
Output Ripple and Noise - 25 MHz
bandwidth
Full load + 10 µF tantalum + 1 µF
ceramic 45 80 mVPK-PK
External Load Capacitance Plus full load (resistive) 10,000 µF
Output Current Range 0 10 ADC
Current Limit Inception Non-latching 10.5 12.5 14 ADC
Peak Short-Circuit Current Non-latching, Short =10 m. 20 30 A
RMS Short-Circuit Current Non-latching 5.3 Arms
Dynamic Response
Load Change 25% of Iout Max, di/dt = 0.1 A/µs Co = 1 µF ceramic 200 mV
di/dt = 5 A/µs Co = 450 µF tantalum + 1 µF ceramic 180 mV
Settling Time to 1% 400 µs
Efficiency
100% Load 87.0 %
50% Load 88.0 %
1 -40 ºC to 85 ºC.
Ambient Temperature [°C]
20 30 40 50 60 70 80 90
Load Current [Adc]
0
2
4
6
8
10
12
500 LFM (2.5 m/s)
400 LFM (2.0 m/s)
300 LFM (1.5 m/s)
200 LFM (1.0 m/s)
100 LFM (0.5 m/s)
30 LFM (0.15 m/s)
Fig. 5.0V.1: Available load current vs. ambient air
temperature and airflow rates for SQ48T10050 converter
with D height pins mounted vertically with Vin = 48 V, air
flowing from pin 3 to pin 1, and maximum FET
temperature ≤ 120 °C.
Ambient Temperature [°C]
20 30 40 50 60 70 80 90
Load Current [Adc]
0
2
4
6
8
10
12
500 LFM (2.5 m/s)
400 LFM (2.0 m/s)
300 LFM (1.5 m/s)
200 LFM (1.0 m/s)
100 LFM (0.5 m/s)
30 LFM (0.15 m/s)
Fig. 5.0V.2: Available load current vs. ambient air
temperature and airflow rates for SQ48T10050 converter
with D height pins mounted horizontally with Vin = 48 V,
air flowing from pin 3 to pin 1, and maximum FET
temperature ≤ 120 °C.
REV. SEP 14, 2005 Page 24 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
SQ48T/S10050 (5.0 Volt Out)
Ambient Temperature [°C]
20 30 40 50 60 70 80 90
Load Current [Adc]
0
2
4
6
8
10
12
500 LFM (2.5 m/s)
400 LFM (2.0 m/s)
300 LFM (1.5 m/s)
200 LFM (1.0 m/s)
100 LFM (0.5 m/s)
30 LFM (0.15 m/s)
Fig. 5.0V.3: Available load current vs. ambient air
temperature and airflow rates for SQ48S10050 converter
mounted vertically with Vin = 48 V, air flowing from pin 3
to pin 1, and maximum FET temperature ≤ 120 °C.
Load Current [Adc]
024681012
Efficiency
0.65
0.70
0.75
0.80
0.85
0.90
0.95
72 V
48 V
36 V
Fig. 5.0V.5: Efficiency vs. load current and input voltage for
SQ48T/S10050 converter mounted vertically with air
flowing from pin 3 to pin 1 at a rate of 300 LFM (1.5 m/s)
and Ta = 25 °C.
Ambient Temperature [°C]
20 30 40 50 60 70 80 90
Load Current [Adc]
0
2
4
6
8
10
12
500 LFM (2.5 m/s)
400 LFM (2.0 m/s)
300 LFM (1.5 m/s)
200 LFM (1.0 m/s)
100 LFM (0.5 m/s)
30 LFM (0.15 m/s)
Fig. 5.0V.4: Available load current vs. ambient air
temperature and airflow rates for SQ48S10050 converter
mounted horizontally with Vin = 48 V, air flowing from pin
3 to pin 1, and maximum FET temperature ≤ 120 °C.
Load Current [Adc]
024681012
Efficiency
0.65
0.70
0.75
0.80
0.85
0.90
0.95
70 C
55 C
40 C
Fig. 5.0V.6: Efficiency vs. load current and ambient
temperature for SQ48T/S10050 converter mounted
vertically with Vin = 48 V and air flowing from pin 3 to pin
1 at a rate of 200 LFM (1.0 m/s).
REV. SEP 14, 2005 Page 25 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
SQ48T/S10050 (5.0 Volt Out)
Load Current [Adc]
024681012
P
ower
Di
ss
i
pa
ti
on
[W]
0.00
2.00
4.00
6.00
8.00
10.00
72 V
48 V
36 V
Fig. 5.0V.7: Power dissipation vs. load current and
input voltage for SQ48T/S10050 converter mounted
vertically with air flowing from pin 3 to pin 1 at a rate of
300 LFM (1.5 m/s) and Ta = 25 °C.
Fig. 5.0V.9: Turn-on transient at full rated load current
(resistive) with no output capacitor at Vin = 48 V,
triggered via ON/OFF pin. Top trace: ON/OFF signal
(5 V/div.). Bottom trace: output voltage (2 V/div.). Time
scale: 2 ms/div.
Load Current [Adc]
024681012
P
ower
Di
ss
i
pa
ti
on
[W]
0.00
2.00
4.00
6.00
8.00
10.00
70 C
55 C
40 C
Fig. 5.0V.8: Power dissipation vs. load current and
ambient temperature for SQ48T/S10050 converter
mounted vertically with Vin = 48 V and air flowing from
pin 3 to pin 1 at a rate of 200 LFM (1.0 m/s).
Fig. 5.0V.10: Turn-on transient at full rated load
current (resistive) plus 10,000 µF at Vin = 48 V,
triggered via ON/OFF pin. Top trace: ON/OFF signal
(5 V/div.). Bottom trace: output voltage (2 V/div.). Time
scale: 2 ms/div.
REV. SEP 14, 2005 Page 26 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
SQ48T/S10050 (5.0 Volt Out)
Fig. 5.0V.11: Output voltage response to load current
step-change (2.5 A – 5 A – 2.5 A) at Vin = 48 V. Top
trace: output voltage (200 mV/div.). Bottom trace: load
current (2 A/div.). Current slew rate: 0.1 A/µs. Co = 1 µF
ceramic. Time scale: 0.2 ms/div.
Fig. 5.0V.13: Output voltage ripple (20 mV/div.) at full
rated load current into a resistive load with Co = 10 µF
tantalum + 1 µF ceramic and Vin = 48 V. Time scale:
1 µs/div.
Fig. 5.0V.12: Output voltage response to load current
step-change (2.5 A – 5 A – 2.5 A) at Vin = 48 V. Top
trace: output voltage (200 mV/div.). Bottom trace: load
current (2 A/div.). Current slew rate: 5 A/µs.
Co = 450 µF tantalum + 1 µF ceramic. Time scale:
0.2 ms/div.
Vout
Vsource
iSiC
1 µF
ceramic
capacitor
10 µH
source
inductance SemiQTM Family
DC-DC
Converter
33 µF
ESR <1
electrolytic
capacitor
Ω
Fig. 5.0V.14: Test Setup for measuring input reflected
ripple currents, ic and is.
REV. SEP 14, 2005 Page 27 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
SQ48T/S10050 (5.0 Volt Out)
Fig. 5.0V.15: Input reflected ripple current, ic
(100 mA/div.), measured at input terminals at full rated
load current and Vin = 48 V. Refer to Fig. 5.0V.14 for
test setup. Time scale: 1 µs/div.
515
6
Iout [Adc]
Vout [Vdc]
0
0
5
2
1
10
4
3
Fig. 5.0V.17: Output voltage vs. load current showing
current limit point and converter shutdown point. Input
voltage has almost no effect on current limit
characteristic.
Fig. 5.0V.16: Input reflected ripple current, is
(10 mA/div.), measured through 10 µH at the source at
full rated load current and Vin = 48 V. Refer to
Fig. 5.0V.14 for test setup. Time scale: 1 µs/div.
Fig. 5.0V.18: Load current (top trace, 10 A/div.,
20 ms/div.) into a 10 m short circuit during restart, at
Vin = 48 V. Bottom trace (10 A/div., 1 ms/div.) is an
expansion of the on-time portion of the top trace.
REV. SEP 14, 2005 Page 28 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
Electrical Specifications: SQ48T/S15033 (3.3 Volt Out)
Conditions: TA = 25 ºC, Airflow = 300 LFM (1.5 m/s), Vin = 48 VDC, Vout = 3.3 VDC, unless otherwise specified.
Parameter Notes Min Typ Max Units
Input Characteristics
Maximum Input Current 15 ADC, 3.3 VDC Out @ 36 VDC In 1.6 ADC
Input Stand-by Current Vin = 48 V, converter disabled 2.6 mADC
Input No Load Current (0 load on the output) Vin = 48 V, converter enabled 42 mADC
Input Reflected-Ripple Current 25 MHz bandwidth 6 mAPK-PK
Input Voltage Ripple Rejection 120 Hz TBD dB
Output Characteristics
Output Voltage Set Point (no load) 3.267 3.300 3.333 VDC
Output Regulation
Over Line ±2 ±5 mV
Over Load ±2 ±5 mV
Output Voltage Range Over line, load and temperature1 3.250 3.350 VDC
Output Ripple and Noise - 25 MHz
bandwidth
Full load + 10 µF tantalum + 1 µF
ceramic 30 50 mVPK-PK
External Load Capacitance Plus full load (resistive) 15,000 µF
Output Current Range 0 15 ADC
Current Limit Inception Non-latching 15.75 18 20 ADC
Peak Short-Circuit Current Non-latching, Short =10 m. 30 40 A
RMS Short-Circuit Current Non-latching 5.3 Arms
Dynamic Response
Load Change 25% of Iout Max, di/dt = 0.1 A/µs Co = 1 µF ceramic 80 mV
di/dt = 5 A/µs Co = 450 µF POS + 1 µF ceramic 140 mV
Settling Time to 1% 100 µs
Efficiency
100% Load 89.5 %
50% Load 89.5 %
1 -40 ºC to 85 ºC.
Ambient Temperature [°C]
20 30 40 50 60 70 80 90
Load Current [Adc]
0
5
10
15
20
500 LFM (2.5 m/s)
400 LFM (2.0 m/s)
300 LFM (1.5 m/s)
200 LFM (1.0 m/s)
100 LFM (0.5 m/s)
30 LFM (0.15 m/s)
Fig. 3.3V.1: Available load current vs. ambient air
temperature and airflow rates for SQ48T15033 converter
with D height pins mounted vertically with Vin = 48 V, air
flowing from pin 3 to pin 1, and maximum FET
temperature ≤ 120 °C.
Ambient Temperature [°C]
20 30 40 50 60 70 80 90
Load Current [Adc]
0
5
10
15
20
500 LFM (2.5 m/s)
400 LFM (2.0 m/s)
300 LFM (1.5 m/s)
200 LFM (1.0 m/s)
100 LFM (0.5 m/s)
30 LFM (0.15 m/s)
Fig. 3.3V.2: Available load current vs. ambient air
temperature and airflow rates for SQ48T15033 converter
with D height pins mounted horizontally with Vin = 48 V,
air flowing from pin 3 to pin 1, and maximum FET
temperature ≤ 120 °C.
REV. SEP 14, 2005 Page 29 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
SQ48T/S15033 (3.3 Volt Out)
Ambient Temperature [°C]
20 30 40 50 60 70 80 90
Load Current [Adc]
0
5
10
15
20
500 LFM (2.5 m/s)
400 LFM (2.0 m/s)
300 LFM (1.5 m/s)
200 LFM (1.0 m/s)
100 LFM (0.5 m/s)
30 LFM (0.15 m/s)
Fig. 3.3V.3: Available load current vs. ambient air
temperature and airflow rates for SQ48S15033 converter
mounted vertically with Vin = 48 V, air flowing from pin 3
to pin 1, and maximum FET temperature ≤ 120 °C.
Load Current [Adc]
0246810121416
Efficiency
0.65
0.70
0.75
0.80
0.85
0.90
0.95
72 V
48 V
36 V
Fig. 3.3V.5: Efficiency vs. load current and input voltage
for SQ48T/S15033 converter mounted vertically with air
flowing from pin 3 to pin 1 at a rate of 300 LFM (1.5 m/s)
and Ta = 25 °C.
Ambient Temperature [°C]
20 30 40 50 60 70 80 90
Load Current [Adc]
0
5
10
15
20
500 LFM (2.5 m/s)
400 LFM (2.0 m/s)
300 LFM (1.5 m/s)
200 LFM (1.0 m/s)
100 LFM (0.5 m/s)
30 LFM (0.15 m/s)
Fig. 3.3V.4: Available load current vs. ambient air
temperature and airflow rates for SQ48S15033 converter
mounted horizontally with Vin = 48 V, air flowing from pin
3 to pin 1, and maximum FET temperature ≤ 120 °C.
Load Current [Adc]
0246810121416
Efficiency
0.65
0.70
0.75
0.80
0.85
0.90
0.95
70 C
55 C
40 C
Fig. 3.3V.6: Efficiency vs. load current and ambient
temperature for SQ48T/S15033 converter mounted
vertically with Vin = 48 V and air flowing from pin 3 to pin
1 at a rate of 200 LFM (1.0 m/s).
REV. SEP 14, 2005 Page 30 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
SQ48T/S15033 (3.3 Volt Out)
Load Current [Adc]
0246810121416
Power Dissipation [W]
0.00
2.00
4.00
6.00
8.00
72 V
48 V
36 V
Fig. 3.3V.7: Power dissipation vs. load current and
input voltage for SQ48T/S15033 converter mounted
vertically with air flowing from pin 3 to pin 1 at a rate of
300 LFM (1.5 m/s) and Ta = 25 °C.
Fig. 3.3V.9: Turn-on transient at full rated load current
(resistive) with no output capacitor at Vin = 48 V,
triggered via ON/OFF pin. Top trace: ON/OFF signal
(5 V/div.). Bottom trace: output voltage (1 V/div.). Time
scale: 2 ms/div.
Load Current [Adc]
0246810121416
Power Dissipation [W]
0.00
2.00
4.00
6.00
8.00
70 C
55 C
40 C
Fig. 3.3V.8: Power dissipation vs. load current and
ambient temperature for SQ48T/S15033 converter
mounted vertically with Vin = 48 V and air flowing from
pin 3 to pin 1 at a rate of 200 LFM (1.0 m/s).
Fig. 3.3V.10: Turn-on transient at full rated load
current (resistive) plus 10,000 µF at Vin = 48 V,
triggered via ON/OFF pin. Top trace: ON/OFF signal
(5 V/div.). Bottom trace: output voltage (1 V/div.). Time
scale: 2 ms/div.
REV. SEP 14, 2005 Page 31 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
SQ48T/S15033 (3.3 Volt Out)
Fig. 3.3V.11: Output voltage response to load current
step-change (3.75 A – 7.5 A – 3.75 A) at Vin = 48 V.
Top trace: output voltage (100 mV/div.). Bottom trace:
load current (5 A/div.). Current slew rate: 0.1 A/µs.
Co = 1 µF ceramic. Time scale: 0.2 ms/div.
Fig. 3.3V.13: Output voltage ripple (20 mV/div.) at full
rated load current into a resistive load with Co = 10 µF
tantalum + 1 µF ceramic and Vin = 48 V. Time scale:
1 µs/div.
Fig. 3.3V.12: Output voltage response to load current
step-change (3.75 A – 7.5 A – 3.75 A) at Vin = 48 V.
Top trace: output voltage (100 mV/div.). Bottom trace:
load current (5 A/div.). Current slew rate: 5 A/µs. Co =
450 µF tantalum + 1 µF ceramic. Time scale: 0.2 ms/div.
Vout
Vsource
iSiC
1 µF
ceramic
capacitor
10 µH
source
inductance SemiQTM Family
DC-DC
Converter
33 µF
ESR <1
electrolytic
capacitor
Ω
Fig. 3.3V.14: Test Setup for measuring input reflected
ripple currents, ic and is.
REV. SEP 14, 2005 Page 32 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
SQ48T/S15033 (3.3 Volt Out)
Fig. 3.3V.15: Input reflected ripple current, ic
(100 mA/div.), measured at input terminals at full rated
load current and Vin = 48 V. Refer to Fig. 3.3V.14 for
test setup. Time scale: 1 µs/div.
20
5
4
Iout [Adc]
Vout [Vdc]
0
0
2
1
10 15
3
Fig. 3.3V.17: Output voltage vs. load current showing
current limit point and converter shutdown point. Input
voltage has almost no effect on current limit
characteristic.
Fig. 3.3V.16: Input reflected ripple current, is
(10 mA/div.), measured through 10 µH at the source at
full rated load current and Vin = 48 V. Refer to
Fig. 3.3V.14 for test setup. Time scale: 1 µs/div.
Fig. 3.3V.18: Load current (top trace, 20 A/div.,
20 ms/div.) into a 10 m short circuit during restart, at
Vin = 48 V. Bottom trace (20 A/div., 1 ms/div.) is an
expansion of the on-time portion of the top trace.
REV. SEP 14, 2005 Page 33 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
Electrical Specifications: SQ48T/S15025 (2.5 Volt Out)
Conditions: TA = 25ºC, Airflow = 300 LFM (1.5 m/s), Vin = 48 VDC, Vout = 2.5 VDC, unless otherwise specified.
Parameter Notes Min Typ Max Units
Input Characteristics
Maximum Input Current 15 ADC, 2.5 VDC Out @ 36 VDC In 1.2 ADC
Input Stand-by Current Vin = 48 V, converter disabled 2.6 mADC
Input No Load Current (0 load on the output) Vin = 48 V, converter enabled 34 mADC
Input Reflected-Ripple Current 25 MHz bandwidth 6 mAPK-PK
Input Voltage Ripple Rejection 120 Hz TBD dB
Output Characteristics
Output Voltage Set Point (no load) 2.475 2.500 2.525 VDC
Output Regulation
Over Line ±2 ±5 mV
Over Load ±2 ±5 mV
Output Voltage Range Over line, load and temperature1 2.462 2.538 VDC
Output Ripple and Noise - 25 MHz
bandwidth
Full load + 10 µF tantalum + 1 µF
ceramic 30 50 mVPK-PK
External Load Capacitance Plus full load (resistive) 15,000 µF
Output Current Range 0 15 ADC
Current Limit Inception Non-latching 15.75 18 20 ADC
Peak Short-Circuit Current Non-latching, Short =10 m. 30 40 A
RMS Short-Circuit Current Non-latching 5.3 Arms
Dynamic Response
Load Change 25% of Iout Max, di/dt = 0.1 A/µs Co = 1 µF ceramic 120 mV
di/dt = 5 A/µs Co = 450 µF POS + 1 µF ceramic 120 mV
Settling Time to 1% 100 µs
Efficiency
100% Load 87.0 %
50% Load 87.5 %
1 -40 ºC to 85 ºC.
Ambient Temperature [°C]
20 30 40 50 60 70 80 90
Load Current [Adc]
0
5
10
15
20
500 LFM (2.5 m/s)
400 LFM (2.0 m/s)
300 LFM (1.5 m/s)
200 LFM (1.0 m/s)
100 LFM (0.5 m/s)
30 LFM (0.15 m/s)
Fig. 2.5V.1: Available load current vs. ambient air
temperature and airflow rates for SQ48T15025 converter
with D height pins mounted vertically with Vin = 48 V, air
flowing from pin 3 to pin 1, and maximum FET
temperature ≤ 120 °C.
Ambient Temperature [°C]
20 30 40 50 60 70 80 90
Load Current [Adc]
0
5
10
15
20
500 LFM (2.5 m/s)
400 LFM (2.0 m/s)
300 LFM (1.5 m/s)
200 LFM (1.0 m/s)
100 LFM (0.5 m/s)
30 LFM (0.15 m/s)
Fig. 2.5V.2: Available load current vs. ambient air
temperature and airflow rates for SQ48T15025 converter
with D height pins mounted horizontally with Vin = 48 V, air
flowing from pin 3 to pin 1, and maximum FET temperature
≤ 120 °C.
REV. SEP 14, 2005 Page 34 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
SQ48T/S15025 (2.5 Volt Out)
Ambient Temperature [°C]
20 30 40 50 60 70 80 90
Load Current [Adc]
0
5
10
15
20
500 LFM (2.5 m/s)
400 LFM (2.0 m/s)
300 LFM (1.5 m/s)
200 LFM (1.0 m/s)
100 LFM (0.5 m/s)
30 LFM (0.15 m/s)
Fig. 2.5V.3: Available load current vs. ambient air
temperature and airflow rates for SQ48S15025 converter
mounted vertically with Vin = 48 V, air flowing from pin 3
to pin 1, and maximum FET temperature ≤ 120 °C.
Load Current [Adc]
0246810121416
Efficiency
0.65
0.70
0.75
0.80
0.85
0.90
0.95
72 V
48 V
36 V
Fig. 2.5V.5: Efficiency vs. load current and input voltage
for SQ48T/S15025 converter mounted vertically with air
flowing from pin 3 to pin 1 at a rate of 300 LFM (1.5 m/s)
and Ta = 25 °C.
Ambient Temperature [°C]
20 30 40 50 60 70 80 90
Load Current [Adc]
0
5
10
15
20
500 LFM (2.5 m/s)
400 LFM (2.0 m/s)
300 LFM (1.5 m/s)
200 LFM (1.0 m/s)
100 LFM (0.5 m/s)
30 LFM (0.15 m/s)
Fig. 2.5V.4: Available load current vs. ambient air
temperature and airflow rates for SQ48S15025 converter
mounted horizontally with Vin = 48 V, air flowing from pin
3 to pin 1, and maximum FET temperature ≤ 120 °C.
Load Current [Adc]
0246810121416
Efficiency
0.65
0.70
0.75
0.80
0.85
0.90
0.95
70 C
55 C
40 C
Fig. 2.5V.6: Efficiency vs. load current and ambient
temperature for SQ48T/S15025 converter mounted
vertically with Vin = 48 V and air flowing from pin 3 to pin
1 at a rate of 200 LFM (1.0 m/s).
REV. SEP 14, 2005 Page 35 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
SQ48T/S15025 (2.5 Volt Out)
Load Current [Adc]
0246810121416
Power Dissipation [W]
0.00
2.00
4.00
6.00
8.00
72 V
48 V
36 V
Fig. 2.5V.7: Power dissipation vs. load current and
input voltage for SQ48T/S15025 converter mounted
vertically with air flowing from pin 3 to pin 1 at a rate of
300 LFM (1.5 m/s) and Ta = 25 °C.
Fig. 2.5V.9: Turn-on transient at full rated load current
(resistive) with no output capacitor at Vin = 48 V,
triggered via ON/OFF pin. Top trace: ON/OFF signal
(5 V/div.). Bottom trace: output voltage (1 V/div.). Time
scale: 2 ms/div.
Load Current [Adc]
0246810121416
Power Dissipation [W]
0.00
2.00
4.00
6.00
8.00
70 C
55 C
40 C
Fig. 2.5V.8: Power dissipation vs. load current and
ambient temperature for SQ48T/S15025 converter
mounted vertically with Vin = 48 V and air flowing from
pin 3 to pin 1 at a rate of 200 LFM (1.0 m/s).
Fig. 2.5V.10: Turn-on transient at full rated load
current (resistive) plus 10,000 µF at Vin = 48 V,
triggered via ON/OFF pin. Top trace: ON/OFF signal
(5 V/div.). Bottom trace: output voltage (1 V/div.). Time
scale: 2 ms/div.
REV. SEP 14, 2005 Page 36 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
SQ48T/S15025 (2.5 Volt Out)
Fig. 2.5V.11: Output voltage response to load current
step-change (3.75 A – 7.5 A – 3.75 A) at Vin = 48 V.
Top trace: output voltage (100 mV/div.). Bottom trace:
load current (5 A/div.). Current slew rate: 0.1 A/µs.
Co = 1 µF ceramic. Time scale: 0.2 ms/div.
Fig. 2.5V.13: Output voltage ripple (20 mV/div.) at full
rated load current into a resistive load with Co = 10 µF
tantalum + 1 µF ceramic and Vin = 48 V. Time scale:
1 µs/div.
Fig. 2.5V.12: Output voltage response to load current
step-change (3.75 A – 7.5 A – 3.75 A) at Vin = 48 V.
Top trace: output voltage (100 mV/div.). Bottom trace:
load current (5 A/div.). Current slew rate: 5 A/µs. Co =
450 µF tantalum + 1 µF ceramic. Time scale: 0.2 ms/div.
Vout
Vsource
iSiC
1 µF
ceramic
capacitor
10 µH
source
inductance SemiQTM Family
DC-DC
Converter
33 µF
ESR <1
electrolytic
capacitor
Ω
Fig. 2.5V.14: Test Setup for measuring input reflected
ripple currents, ic and is.
REV. SEP 14, 2005 Page 37 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
SQ48T/S15025 (2.5 Volt Out)
Fig. 2.5V.15: Input reflected ripple current, ic
(100 mA/div.), measured at input terminals at full rated
load current and Vin = 48 V. Refer to Fig. 2.5V.14 for
test setup. Time scale: 1 µs/div.
520
3
Iout [Adc]
Vout [Vdc]
0
0
1
10 15
2
Fig. 2.5V.17: Output voltage vs. load current showing
current limit point and converter shutdown point. Input
voltage has almost no effect on current limit
characteristic.
Fig. 2.5V.16: Input reflected ripple current, is
(10 mA/div.), measured through 10 µH at the source at
full rated load current and Vin = 48 V. Refer to
Fig. 2.5V.14 for test setup. Time scale: 1 µs/div.
Fig. 2.5V.18: Load current (top trace, 20 A/div.,
20 ms/div.) into a 10 m short circuit during restart, at
Vin = 48 V. Bottom trace (20 A/div., 1 ms/div.) is an
expansion of the on-time portion of the top trace.
REV. SEP 14, 2005 Page 38 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
Electrical Specifications: SQ48T/S15020 (2.0 Volt Out)
Conditions: TA = 25 ºC, Airflow = 300 LFM (1.5 m/s), Vin = 48 VDC, Vout = 2.0 VDC, unless otherwise specified.
Parameter Notes Min Typ Max Units
Input Characteristics
Maximum Input Current 15 ADC, 2.0 VDC Out @ 36 VDC In 1.0 ADC
Input Stand-by Current Vin = 48 V, converter disabled 3 mADC
Input No Load Current (0 load on the output) Vin = 48 V, converter enabled 31 mADC
Input Reflected-Ripple Current 25 MHz bandwidth 6 mAPK-PK
Input Voltage Ripple Rejection 120 Hz TBD dB
Output Characteristics
Output Voltage Set Point (no load) 1.98 2.000 2.02 VDC
Output Regulation
Over Line ±2 ±5 mV
Over Load ±2 ±5 mV
Output Voltage Range Over line, load and temperature1 1.970 2.030 VDC
Output Ripple and Noise - 25 MHz
bandwidth
Full load + 10 µF tantalum + 1 µF
ceramic 30 50 mVPK-PK
External Load Capacitance Plus full load (resistive) 15,000 µF
Output Current Range 0 15 ADC
Current Limit Inception Non-latching 15.75 18 20 ADC
Peak Short-Circuit Current Non-latching, Short =10 m. 30 40 A
RMS Short-Circuit Current Non-latching 5.3 Arms
Dynamic Response
Load Change 25% of Iout Max, di/dt = 0.1 A/µs Co = 1 µF ceramic 80 mV
di/dt = 5 A/µs Co = 450 µF POS + 1 µF ceramic 60 mV
Settling Time to 1% 60 µs
Efficiency
100% Load 86.5 %
50% Load 87.0 %
1 -40 ºC to 85 ºC.
Ambient Temperature [°C]
20 30 40 50 60 70 80 90
Load Current [Adc]
0
5
10
15
20
500 LFM (2.5 m/s)
400 LFM (2.0 m/s)
300 LFM (1.5 m/s)
200 LFM (1.0 m/s)
100 LFM (0.5 m/s)
30 LFM (0.15 m/s)
Fig. 2.0V.1: Available load current vs. ambient air
temperature and airflow rates for SQ48T15020 converter
with D height pins mounted vertically with Vin = 48 V, air
flowing from pin 3 to pin 1, and maximum FET
temperature ≤ 120 °C.
Ambient Temperature [°C]
20 30 40 50 60 70 80 90
Load Current [Adc]
0
5
10
15
20
500 LFM (2.5 m/s)
400 LFM (2.0 m/s)
300 LFM (1.5 m/s)
200 LFM (1.0 m/s)
100 LFM (0.5 m/s)
30 LFM (0.15 m/s)
Fig. 2.0V.2: Available load current vs. ambient air
temperature and airflow rates for SQ48T15020 converter
with D height pins mounted horizontally with Vin = 48 V,
air flowing from pin 3 to pin 1, and maximum FET
temperature ≤ 120 °C.
REV. SEP 14, 2005 Page 39 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
SQ48T/S15020 (2.0 Volt Out)
Ambient Temperature [°C]
20 30 40 50 60 70 80 90
Load Current [Adc]
0
5
10
15
20
500 LFM (2.5 m/s)
400 LFM (2.0 m/s)
300 LFM (1.5 m/s)
200 LFM (1.0 m/s)
100 LFM (0.5 m/s)
30 LFM (0.15 m/s)
Fig. 2.0V.3: Available load current vs. ambient air
temperature and airflow rates for SQ48S15020 converter
mounted vertically with Vin = 48 V, air flowing from pin 3
to pin 1, and maximum FET temperature ≤ 120 °C.
Load Current [Adc]
0246810121416
Efficiency
0.65
0.70
0.75
0.80
0.85
0.90
0.95
72 V
48 V
36 V
Fig. 2.0V.5: Efficiency vs. load current and input voltage
for SQ48T/S15020 converter mounted vertically with air
flowing from pin 3 to pin 1 at a rate of 300 LFM (1.5 m/s)
and Ta = 25 °C.
Ambient Temperature [°C]
20 30 40 50 60 70 80 90
Load Current [Adc]
0
5
10
15
20
500 LFM (2.5 m/s)
400 LFM (2.0 m/s)
300 LFM (1.5 m/s)
200 LFM (1.0 m/s)
100 LFM (0.5 m/s)
30 LFM (0.15 m/s)
Fig. 2.0V.4: Available load current vs. ambient air
temperature and airflow rates for SQ48S15020 converter
mounted horizontally with Vin = 48 V, air flowing from pin
3 to pin 1, and maximum FET temperature ≤ 120 °C.
Load Current [Adc]
0246810121416
Efficiency
0.65
0.70
0.75
0.80
0.85
0.90
0.95
70 C
55 C
40 C
Fig. 2.0V.6: Efficiency vs. load current and ambient
temperature for SQ48T/S15020 converter mounted
vertically with Vin = 48 V and air flowing from pin 3 to pin
1 at a rate of 200 LFM (1.0 m/s).
REV. SEP 14, 2005 Page 40 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
SQ48T/S15020 (2.0 Volt Out)
Load Current [Adc]
0246810121416
Power Dissipation [W]
0.00
1.00
2.00
3.00
4.00
5.00
6.00
72 V
48 V
36 V
Fig. 2.0V.7: Power dissipation vs. load current and
input voltage for SQ48T/S15020 converter mounted
vertically with air flowing from pin 3 to pin 1 at a rate of
300 LFM (1.5 m/s) and Ta = 25 °C.
Fig. 2.0V.9: Turn-on transient at full rated load current
(resistive) with no output capacitor at Vin = 48 V,
triggered via ON/OFF pin. Top trace: ON/OFF signal
(5 V/div.). Bottom trace: output voltage (1 V/div.). Time
scale: 2 ms/div.
Load Current [Adc]
0246810121416
Power Dissipation [W]
0.00
1.00
2.00
3.00
4.00
5.00
6.00
70 C
55 C
40 C
Fig. 2.0V.8: Power dissipation vs. load current and
ambient temperature for SQ48T/S15020 converter
mounted vertically with Vin = 48 V and air flowing from
pin 3 to pin 1 at a rate of 200 LFM (1.0 m/s).
Fig. 2.0V.10: Turn-on transient at full rated load
current (resistive) plus 10,000 µF at Vin = 48 V,
triggered via ON/OFF pin. Top trace: ON/OFF signal
(5 V/div.). Bottom trace: output voltage (1 V/div.). Time
scale: 2 ms/div.
REV. SEP 14, 2005 Page 41 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
SQ48T/S15020 (2.0 Volt Out)
Fig. 2.0V.11: Output voltage response to load current
step-change (3.75 A – 7.5 A – 3.75 A) at Vin = 48 V.
Top trace: output voltage (100 mV/div.). Bottom trace:
load current (5 A/div.). Current slew rate: 0.1 A/µs.
Co = 1 µF ceramic. Time scale: 0.2 ms/div.
Fig. 2.0V.13: Output voltage ripple (20 mV/div.) at full
rated load current into a resistive load with Co = 10 µF
tantalum + 1 µF ceramic and Vin = 48 V. Time scale:
1 µs/div.
Fig. 2.0V.12: Output voltage response to load current
step-change (3.75 A – 7.5 A – 3.75 A) at Vin = 48 V.
Top trace: output voltage (100 mV/div.). Bottom trace:
load current (5 A/div.). Current slew rate: 5 A/µs. Co =
450 µF tantalum + 1 µF ceramic. Time scale: 0.2 ms/div.
Vout
Vsource
iSiC
1 µF
ceramic
capacitor
10 µH
source
inductance SemiQTM Family
DC-DC
Converter
33 µF
ESR <1
electrolytic
capacitor
Ω
Fig. 2.0V.14: Test Setup for measuring input reflected
ripple currents, ic and is.
REV. SEP 14, 2005 Page 42 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
SQ48T/S15020 (2.0 Volt Out)
Fig. 2.0V.15: Input reflected ripple current, ic
(100 mA/div.), measured at input terminals at full rated
load current and Vin = 48 V. Refer to Fig. 2.0V.14 for
test setup. Time scale: 1 µs/div.
520
3
Iout [Adc]
Vout [Vdc]
0
0
1
10 15
2
Fig. 2.0V.17: Output voltage vs. load current showing
current limit point and converter shutdown point. Input
voltage has almost no effect on current limit
characteristic.
Fig. 2.0V.16: Input reflected ripple current, is
(10 mA/div.), measured through 10 µH at the source at
full rated load current and Vin = 48 V. Refer to
Fig. 2.0V.14 for test setup. Time scale: 1 µs/div.
Fig. 2.0V.18: Load current (top trace, 20 A/div.,
20 ms/div.) into a 10 m short circuit during restart, at
Vin = 48 V. Bottom trace (20 A/div., 1 ms/div.) is an
expansion of the on-time portion of the top trace.
REV. SEP 14, 2005 Page 43 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
Electrical Specifications: SQ48T/S15018 (1.8 Volt Out)
Conditions: TA = 25 ºC, Airflow = 300 LFM (1.5 m/s), Vin = 48 VDC, Vout = 1.8 VDC, unless otherwise specified.
Parameter Notes Min Typ Max Units
Input Characteristics
Maximum Input Current 15 ADC, 1.8 VDC Out @ 36 VDC In 0.9 ADC
Input Stand-by Current Vin = 48 V, converter disabled 2.6 mADC
Input No Load Current (0 load on the output) Vin = 48 V, converter enabled 29 mADC
Input Reflected-Ripple Current 25 MHz bandwidth 6 mAPK-PK
Input Voltage Ripple Rejection 120 Hz TBD dB
Output Characteristics
Output Voltage Set Point (no load) 1.782 1.800 1.818 VDC
Output Regulation
Over Line ±2 ±4 mV
Over Load ±2 ±5 mV
Output Voltage Range Over line, load and temperature1 1.773 1.827 VDC
Output Ripple and Noise - 25 MHz
bandwidth
Full load + 10 µF tantalum + 1 µF
ceramic 30 50 mVPK-PK
External Load Capacitance Plus full load (resistive) 15,000 µF
Output Current Range 0 15 ADC
Current Limit Inception Non-latching 15.75 18 20 ADC
Peak Short-Circuit Current Non-latching, Short =10 m. 30 40 A
RMS Short-Circuit Current Non-latching 5.3 Arms
Dynamic Response
Load Change 25% of Iout Max, di/dt = 0.1 A/µs Co = 1 µF ceramic 80 mV
di/dt = 5 A/µs Co = 450 µF POS + 1 µF ceramic 100 mV
Settling Time to 1% 100 µs
Efficiency
100% Load 85.5 %
50% Load 86.0 %
1 -40 ºC to 85 ºC.
Ambient Temperature [°C]
20 30 40 50 60 70 80 90
Load Current [Adc]
0
5
10
15
20
500 LFM (2.5 m/s)
400 LFM (2.0 m/s)
300 LFM (1.5 m/s)
200 LFM (1.0 m/s)
100 LFM (0.5 m/s)
30 LFM (0.15 m/s)
Fig. 1.8V.1: Available load current vs. ambient air
temperature and airflow rates for SQ48T15018 converter
with D height pins mounted vertically with Vin = 48 V, air
flowing from pin 3 to pin 1, and maximum FET
temperature ≤ 120 °C.
Ambient Temperature [°C]
20 30 40 50 60 70 80 90
Load Current [Adc]
0
5
10
15
20
500 LFM (2.5 m/s)
400 LFM (2.0 m/s)
300 LFM (1.5 m/s)
200 LFM (1.0 m/s)
100 LFM (0.5 m/s)
30 LFM (0.15 m/s)
Fig. 1.8V.2: Available load current vs. ambient air
temperature and airflow rates for SQ48T15018 converter
with D height pins mounted horizontally with Vin = 48 V,
air flowing from pin 3 to pin 1, and maximum FET
temperature ≤ 120 °C.
REV. SEP 14, 2005 Page 44 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
SQ48T/S15018 (1.8 Volt Out)
Ambient Temperature [°C]
20 30 40 50 60 70 80 90
Load Current [Adc]
0
5
10
15
20
500 LFM (2.5 m/s)
400 LFM (2.0 m/s)
300 LFM (1.5 m/s)
200 LFM (1.0 m/s)
100 LFM (0.5 m/s)
30 LFM (0.15 m/s)
Fig. 1.8V.3: Available load current vs. ambient air
temperature and airflow rates for SQ48S15018 converter
mounted vertically with Vin = 48 V, air flowing from pin 3
to pin 1, and maximum FET temperature ≤ 120 °C.
Load Current [Adc]
0246810121416
Efficiency
0.65
0.70
0.75
0.80
0.85
0.90
0.95
72 V
48 V
36 V
Fig. 1.8V.5: Efficiency vs. load current and input voltage
for SQ48T/S15018 converter mounted vertically with air
flowing from pin 3 to pin 1 at a rate of 300 LFM (1.5 m/s)
and Ta = 25 °C.
Ambient Temperature [°C]
20 30 40 50 60 70 80 90
Load Current [Adc]
0
5
10
15
20
500 LFM (2.5 m/s)
400 LFM (2.0 m/s)
300 LFM (1.5 m/s)
200 LFM (1.0 m/s)
100 LFM (0.5 m/s)
30 LFM (0.15 m/s)
Fig. 1.8V.4: Available load current vs. ambient air
temperature and airflow rates for SQ48S15018 converter
mounted horizontally with Vin = 48 V, air flowing from pin
3 to pin 1, and maximum FET temperature ≤ 120 °C.
Load Current [Adc]
0246810121416
Efficiency
0.65
0.70
0.75
0.80
0.85
0.90
0.95
70 C
55 C
40 C
Fig. 1.8V.6: Efficiency vs. load current and ambient
temperature for SQ48T/S15018 converter mounted
vertically with Vin = 48 V and air flowing from pin 3 to pin
1 at a rate of 200 LFM (1.0 m/s).
REV. SEP 14, 2005 Page 45 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
SQ48T/S15018 (1.8 Volt Out)
Load Current [Adc]
0246810121416
Power Dissipation [W]
0.00
1.00
2.00
3.00
4.00
5.00
6.00
72 V
48 V
36 V
Fig. 1.8V.7: Power dissipation vs. load current and
input voltage for SQ48T/S15018 converter mounted
vertically with air flowing from pin 3 to pin 1 at a rate of
300 LFM (1.5 m/s) and Ta = 25 °C.
Fig. 1.8V.9: Turn-on transient at full rated load current
(resistive) with no output capacitor at Vin = 48 V,
triggered via ON/OFF pin. Top trace: ON/OFF signal
(5 V/div.). Bottom trace: output voltage (1 V/div.). Time
scale: 2 ms/div.
Load Current [Adc]
0246810121416
Power Dissipation [W]
0.00
1.00
2.00
3.00
4.00
5.00
6.00
70 C
55 C
40 C
Fig. 1.8V.8: Power dissipation vs. load current and
ambient temperature for SQ48T/S15018 converter
mounted vertically with Vin = 48 V and air flowing from
pin 3 to pin 1 at a rate of 200 LFM (1.0 m/s).
Fig. 1.8V.10: Turn-on transient at full rated load
current (resistive) plus 10,000 µF at Vin = 48 V,
triggered via ON/OFF pin. Top trace: ON/OFF signal
(5 V/div.). Bottom trace: output voltage (1 V/div.). Time
scale: 2 ms/div.
REV. SEP 14, 2005 Page 46 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
SQ48T/S15018 (1.8 Volt Out)
Fig. 1.8V.11: Output voltage response to load current
step-change (3.75 A – 7.5 A – 3.75 A) at Vin = 48 V.
Top trace: output voltage (100 mV/div.). Bottom trace:
load current (5 A/div.). Current slew rate: 0.1 A/µs.
Co = 1 µF ceramic. Time scale: 0.2 ms/div.
Fig. 1.8V.13: Output voltage ripple (20 mV/div.) at full
rated load current into a resistive load with Co = 10 µF
tantalum + 1 µF ceramic and Vin = 48 V. Time scale:
1 µs/div.
Fig. 1.8V.12: Output voltage response to load current
step-change (3.75 A – 7.5 A – 3.75 A) at Vin = 48 V.
Top trace: output voltage (100 mV/div.). Bottom trace:
load current (5 A/div.). Current slew rate: 5 A/µs. Co =
450 µF tantalum + 1 µF ceramic. Time scale: 0.2 ms/div.
Vout
Vsource
iSiC
1 µF
ceramic
capacitor
10 µH
source
inductance SemiQTM Family
DC-DC
Converter
33 µF
ESR <1
electrolytic
capacitor
Ω
Fig. 1.8V.14: Test Setup for measuring input reflected
ripple currents, ic and is.
REV. SEP 14, 2005 Page 47 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
SQ48T/S15018 (1.8 Volt Out)
Fig. 1.8V.15: Input reflected ripple current, ic
(100 mA/div.), measured at input terminals at full rated
load current and Vin = 48 V. Refer to Fig. 1.8V.14 for
test setup. Time scale: 1 µs/div.
520
3
Iout [Adc]
Vout [Vdc]
0
0
1
10 15
2
Fig. 1.8V.17: Output voltage vs. load current showing
current limit point and converter shutdown point. Input
voltage has almost no effect on current limit
characteristic.
Fig. 1.8V.16: Input reflected ripple current, is
(10 mA/div.), measured through 10 µH at the source at
full rated load current and Vin = 48 V. Refer to
Fig. 1.8V.14 for test setup. Time scale: 1 µs/div.
Fig. 1.8V.18: Load current (top trace, 20 A/div.,
20 ms/div.) into a 10 m short circuit during restart, at
Vin = 48 V. Bottom trace (20 A/div., 1 ms/div.) is an
expansion of the on-time portion of the top trace.
REV. SEP 14, 2005 Page 48 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
Electrical Specifications: SQ48T/S15015 (1.5 Volt Out)
Conditions: TA = 25 ºC, Airflow = 300 LFM (1.5 m/s), Vin = 48 VDC, Vout = 1.5 VDC, unless otherwise specified.
Parameter Notes Min Typ Max Units
Input Characteristics
Maximum Input Current 15 ADC, 1.5 VDC Out @ 36 VDC In 0.75 ADC
Input Stand-by Current Vin = 48 V, converter disabled 2.6 mADC
Input No Load Current (0 load on the output) Vin = 48 V, converter enabled 25 mADC
Input Reflected-Ripple Current 25 MHz bandwidth 6 mAPK-PK
Input Voltage Ripple Rejection 120 Hz TBD dB
Output Characteristics
Output Voltage Set Point (no load) 1.485 1.500 1.515 VDC
Output Regulation
Over Line ±2 ±4 mV
Over Load ±2 ±4 mV
Output Voltage Range Over line, load and temperature1 1.477 1.523 VDC
Output Ripple and Noise - 25 MHz
bandwidth
Full load + 10 µF tantalum + 1 µF
ceramic 30 50 mVPK-PK
External Load Capacitance Plus full load (resistive) 15,000 µF
Output Current Range 0 15 ADC
Current Limit Inception Non-latching 15.75 18 20 ADC
Peak Short-Circuit Current Non-latching, Short =10 m. 30 40 A
RMS Short-Circuit Current Non-latching 5.3 Arms
Dynamic Response
Load Change 25% of Iout Max, di/dt = 0.1 A/µs Co = 1 µF ceramic 80 mV
di/dt = 5 A/µs Co = 450 µF POS + 1 µF ceramic 120 mV
Settling Time to 1% 100 µs
Efficiency
100% Load 84.5 %
50% Load 85.0 %
1 -40 ºC to 85 ºC.
Ambient Temperature [°C]
20 30 40 50 60 70 80 90
Load Current [Adc]
0
5
10
15
20
500 LFM (2.5 m/s)
400 LFM (2.0 m/s)
300 LFM (1.5 m/s)
200 LFM (1.0 m/s)
100 LFM (0.5 m/s)
30 LFM (0.15 m/s)
Fig. 1.5V.1: Available load current vs. ambient air
temperature and airflow rates for SQ48T15015 converter
with D height pins mounted vertically with Vin = 48 V, air
flowing from pin 3 to pin 1, and maximum FET
temperature ≤ 120 °C
Ambient Temperature [°C]
20 30 40 50 60 70 80 90
Load Current [Adc]
0
5
10
15
20
500 LFM (2.5 m/s)
400 LFM (2.0 m/s)
300 LFM (1.5 m/s)
200 LFM (1.0 m/s)
100 LFM (0.5 m/s)
30 LFM (0.15 m/s)
Fig. 1.5V.2: Available load current vs. ambient air
temperature and airflow rates for SQ48T15015 converter
with D height pins mounted horizontally with Vin = 48 V,
air flowing from pin 3 to pin 1, and maximum FET
temperature ≤ 120 °C.
REV. SEP 14, 2005 Page 49 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
SQ48T/S15015 (1.5 Volt Out)
Ambient Temperature [°C]
20 30 40 50 60 70 80 90
Load Current [Adc]
0
5
10
15
20
500 LFM (2.5 m/s)
400 LFM (2.0 m/s)
300 LFM (1.5 m/s)
200 LFM (1.0 m/s)
100 LFM (0.5 m/s)
30 LFM (0.15 m/s)
Fig. 1.5V.3: Available load current vs. ambient air
temperature and airflow rates for SQ48S15015 converter
mounted vertically with Vin = 48 V, air flowing from pin 3
to pin 1, and maximum FET temperature ≤ 120 °C.
Load Current [Adc]
0246810121416
Efficiency
0.65
0.70
0.75
0.80
0.85
0.90
0.95
72 V
48 V
36 V
Fig. 1.5V.5: Efficiency vs. load current and input voltage
for SQ48T/S15015 converter mounted vertically with air
flowing from pin 3 to pin 1 at a rate of 300 LFM (1.5 m/s)
and Ta = 25 °C.
Ambient Temperature [°C]
20 30 40 50 60 70 80 90
Load Current [Adc]
0
5
10
15
20
500 LFM (2.5 m/s)
400 LFM (2.0 m/s)
300 LFM (1.5 m/s)
200 LFM (1.0 m/s)
100 LFM (0.5 m/s)
30 LFM (0.15 m/s)
Fig. 1.5V.4: Available load current vs. ambient air
temperature and airflow rates for SQ48S15015 converter
mounted horizontally with Vin = 48 V, air flowing from pin
3 to pin 1, and maximum FET temperature ≤ 120 °C.
Load Current [Adc]
0246810121416
Efficiency
0.65
0.70
0.75
0.80
0.85
0.90
0.95
70 C
55 C
40 C
Fig. 1.5V.6: Efficiency vs. load current and ambient
temperature for SQ48T/S15015 converter mounted
vertically with Vin = 48 V and air flowing from pin 3 to pin
1 at a rate of 200 LFM (1.0 m/s).
REV. SEP 14, 2005 Page 50 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
SQ48T/S15015 (1.5 Volt Out)
Load Current [Adc]
0246810121416
Power Dissipation [W]
0.00
1.00
2.00
3.00
4.00
5.00
6.00
72 V
48 V
36 V
Fig. 1.5V.7: Power dissipation vs. load current and
input voltage for SQ48T/S15015 converter mounted
vertically with air flowing from pin 3 to pin 1 at a rate of
300 LFM (1.5 m/s) and Ta = 25 °C.
Fig. 1.5V.9: Turn-on transient at full rated load current
(resistive) with no output capacitor at Vin = 48 V,
triggered via ON/OFF pin. Top trace: ON/OFF signal
(5 V/div.). Bottom trace: output voltage (0.5 V/div.). Time
scale: 2 ms/div.
Load Current [Adc]
0246810121416
Power Dissipation [W]
0.00
1.00
2.00
3.00
4.00
5.00
6.00
70 C
55 C
40 C
Fig. 1.5V.8: Power dissipation vs. load current and
ambient temperature for SQ48T/S15015 converter
mounted vertically with Vin = 48 V and air flowing from
pin 3 to pin 1 at a rate of 200 LFM (1.0 m/s).
Fig. 1.5V.10: Turn-on transient at full rated load
current (resistive) plus 10,000 µF at Vin = 48 V,
triggered via ON/OFF pin. Top trace: ON/OFF signal
(5 V/div.). Bottom trace: output voltage (0.5 V/div.).
Time scale: 2 ms/div.
REV. SEP 14, 2005 Page 51 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
SQ48T/S15015 (1.5 Volt Out)
Fig. 1.5V.11: Output voltage response to load current
step-change (3.75 A – 7.5 A – 3.75 A) at Vin = 48 V.
Top trace: output voltage (100 mV/div.). Bottom trace:
load current (5 A/div.). Current slew rate: 0.1 A/µs.
Co = 1 µF ceramic. Time scale: 0.2 ms/div.
Fig. 1.5V.13: Output voltage ripple (20 mV/div.) at full
rated load current into a resistive load with Co = 10 µF
tantalum + 1 µF ceramic and Vin = 48 V. Time scale:
1 µs/div.
Fig. 1.5V.12: Output voltage response to load current
step-change (3.75 A – 7.5 A – 3.75 A) at Vin = 48 V.
Top trace: output voltage (100 mV/div.). Bottom trace:
load current (5 A/div.). Current slew rate: 5 A/µs. Co =
450 µF tantalum + 1 µF ceramic. Time scale: 0.2 ms/div.
Vout
Vsource
iSiC
1 µF
ceramic
capacitor
10 µH
source
inductance SemiQTM Family
DC-DC
Converter
33 µF
ESR <1
electrolytic
capacitor
Ω
Fig. 1.5V.14: Test Setup for measuring input reflected
ripple currents, ic and is.
REV. SEP 14, 2005 Page 52 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
SQ48T/S15015 (1.5 Volt Out)
Fig. 1.5V.15: Input reflected ripple current, ic
(100 mA/div.), measured at input terminals at full rated
load current and Vin = 48 V. Refer to Fig. 1.5V.14 for
test setup. Time scale: 1 µs/div.
520
2.0
Iout [Adc]
Vout [Vdc]
0
0
1.5
1.0
0.5
10 15
Fig. 1.5V.17: Output voltage vs. load current showing
current limit point and converter shutdown point. Input
voltage has almost no effect on current limit
characteristic.
Fig. 1.5V.16: Input reflected ripple current, is
(10 mA/div.), measured through 10 µH at the source at
full rated load current and Vin = 48 V. Refer to
Fig. 1.5V.14 for test setup. Time scale: 1 µs/div.
Fig. 1.5V.18: Load current (top trace, 20 A/div.,
20 ms/div.) into a 10 m short circuit during restart, at
Vin = 48 V. Bottom trace (20 A/div., 1 ms/div.) is an
expansion of the on-time portion of the top trace.
REV. SEP 14, 2005 Page 53 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
Electrical Specifications: SQ48T/S15012 (1.2 Volt Out)
Conditions: TA = 25 ºC, Airflow = 300 LFM (1.5 m/s), Vin = 48 VDC, Vout = 1.2 VDC, unless otherwise specified.
Parameter Notes Min Typ Max Units
Input Characteristics
Maximum Input Current 15 ADC, 1.2 VDC Out @ 36 VDC In 0.62 ADC
Input Stand-by Current Vin = 48 V, converter disabled 2.6 mADC
Input No Load Current (0 load on the output) Vin = 48 V, converter enabled 22 mADC
Input Reflected-Ripple Current 25 MHz bandwidth 6 mAPK-PK
Input Voltage Ripple Rejection 120 Hz TBD dB
Output Characteristics
Output Voltage Set Point (no load) 1.188 1.200 1.212 VDC
Output Regulation
Over Line ±1 ±3 mV
Over Load ±1 ±3 mV
Output Voltage Range Over line, load and temperature1 1.182 1.218 VDC
Output Ripple and Noise - 25 MHz
bandwidth
Full load + 10 µF tantalum + 1 µF
ceramic 30 50 mVPK-PK
External Load Capacitance Plus full load (resistive) 15,000 µF
Output Current Range 0 15 ADC
Current Limit Inception Non-latching 15.75 18 20 ADC
Peak Short-Circuit Current Non-latching, Short =10 m. 30 40 A
RMS Short-Circuit Current Non-latching 5.3 Arms
Dynamic Response
Load Change 25% of Iout Max, di/dt = 0.1 A/µs Co = 1 µF ceramic 90 mV
di/dt = 5 A/µs Co = 450 µF tantalum + 1 µF ceramic 120 mV
Settling Time to 1% 100 µs
Efficiency
100% Load 82.0 %
50% Load 83.0 %
1 -40 ºC to 85 ºC.
Ambient Temperature [°C]
20 30 40 50 60 70 80 90
Load Current [Adc]
0
5
10
15
20
500 LFM (2.5 m/s)
400 LFM (2.0 m/s)
300 LFM (1.5 m/s)
200 LFM (1.0 m/s)
100 LFM (0.5 m/s)
30 LFM (0.15 m/s)
Fig. 1.2V.1: Available load current vs. ambient air
temperature and airflow rates for SQ48T15012 converter
with D height pins mounted vertically with Vin = 48 V, air
flowing from pin 3 to pin 1, and maximum FET
temperature ≤ 120 °C.
Ambient Temperature [°C]
20 30 40 50 60 70 80 90
Load Current [Adc]
0
5
10
15
20
500 LFM (2.5 m/s)
400 LFM (2.0 m/s)
300 LFM (1.5 m/s)
200 LFM (1.0 m/s)
100 LFM (0.5 m/s)
30 LFM (0.15 m/s)
Fig. 1.2V.2: Available load current vs. ambient air
temperature and airflow rates for SQ48T15012 converter
with D height pins mounted horizontally with Vin = 48 V,
air flowing from pin 3 to pin 1, and maximum FET
temperature ≤ 120 °C.
REV. SEP 14, 2005 Page 54 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
SQ48T/S15012 (1.2 Volt Out)
Ambient Temperature [°C]
20 30 40 50 60 70 80 90
Load Current [Adc]
0
5
10
15
20
500 LFM (2.5 m/s)
400 LFM (2.0 m/s)
300 LFM (1.5 m/s)
200 LFM (1.0 m/s)
100 LFM (0.5 m/s)
30 LFM (0.15 m/s)
Fig. 1.2V.3: Available load current vs. ambient air
temperature and airflow rates for SQ48S15012 converter
mounted vertically with Vin = 48 V, air flowing from pin 3
to pin 1, and maximum FET temperature ≤ 120 °C.
Load Current [Adc]
0246810121416
Efficiency
0.60
0.65
0.70
0.75
0.80
0.85
0.90
72 V
48 V
36 V
Fig. 1.2V.5: Efficiency vs. load current and input voltage for
SQ48T/S15012 converter mounted vertically with air
flowing from pin 3 to pin 1 at a rate of 300 LFM (1.5 m/s)
and Ta = 25 °C.
Ambient Temperature [°C]
20 30 40 50 60 70 80 90
Load Current [Adc]
0
5
10
15
20
500 LFM (2.5 m/s)
400 LFM (2.0 m/s)
300 LFM (1.5 m/s)
200 LFM (1.0 m/s)
100 LFM (0.5 m/s)
30 LFM (0.15 m/s)
Fig. 1.2V.4: Available load current vs. ambient air
temperature and airflow rates for SQ48S15012 converter
mounted horizontally with Vin = 48 V, air flowing from pin
3 to pin 1, and maximum FET temperature ≤ 120 °C.
Load Current [Adc]
0246810121416
Efficiency
0.60
0.65
0.70
0.75
0.80
0.85
0.90
70 C
55 C
40 C
Fig. 1.2V.6: Efficiency vs. load current and ambient
temperature for SQ48T/S15012 converter mounted
vertically with Vin = 48 V and air flowing from pin 3 to pin
1 at a rate of 200 LFM (1.0 m/s).
REV. SEP 14, 2005 Page 55 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
SQ48T/S15012 (1.2 Volt Out)
Load Current [Adc]
0246810121416
Power Dissipation [W]
0.00
1.00
2.00
3.00
4.00
5.00
72 V
48 V
36 V
Fig. 1.2V.7: Power dissipation vs. load current and
input voltage for SQ48T/S15012 converter mounted
vertically with air flowing from pin 3 to pin 1 at a rate of
300 LFM (1.5 m/s) and Ta = 25 °C.
Fig. 1.2V.9: Turn-on transient at full rated load current
(resistive) with no output capacitor at Vin = 48 V,
triggered via ON/OFF pin. Top trace: ON/OFF signal
(5 V/div.). Bottom trace: output voltage (0.5 V/div.). Time
scale: 2 ms/div.
Load Current [Adc]
0246810121416
Power Dissipation [W]
0.00
1.00
2.00
3.00
4.00
5.00
70 C
55 C
40 C
Fig. 1.2V.8: Power dissipation vs. load current and
ambient temperature for SQ48T/S15012 converter
mounted vertically with Vin = 48 V and air flowing from
pin 3 to pin 1 at a rate of 200 LFM (1.0 m/s).
Fig. 1.2V.10: Turn-on transient at full rated load
current (resistive) plus 10,000 µF at Vin = 48 V,
triggered via ON/OFF pin. Top trace: ON/OFF signal
(5 V/div.). Bottom trace: output voltage (0.5 V/div.).
Time scale: 2 ms/div.
REV. SEP 14, 2005 Page 56 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
SQ48T/S15012 (1.2 Volt Out)
Fig. 1.2V.11: Output voltage response to load current
step-change (3.75 A – 7.5 A – 3.75 A) at Vin = 48 V.
Top trace: output voltage (100 mV/div.). Bottom trace:
load current (5 A/div.). Current slew rate: 0.1 A/µs.
Co = 1 µF ceramic. Time scale: 0.2 ms/div.
Fig. 1.2V.13: Output voltage ripple (20 mV/div.) at full
rated load current into a resistive load with Co = 10 µF
tantalum + 1 µF ceramic and Vin = 48 V. Time scale:
1 µs/div.
Fig. 1.2V.12: Output voltage response to load current
step-change (3.75 A – 7.5 A – 3.75 A) at Vin = 48 V.
Top trace: output voltage (100 mV/div.). Bottom trace:
load current (5 A/div.). Current slew rate: 5 A/µs. Co =
450 µF tantalum + 1 µF ceramic. Time scale: 0.2 ms/div.
Vout
Vsource
iSiC
1 µF
ceramic
capacitor
10 µH
source
inductance SemiQTM Family
DC-DC
Converter
33 µF
ESR <1
electrolytic
capacitor
Ω
Fig. 1.2V.14: Test Setup for measuring input reflected
ripple currents, ic and is.
REV. SEP 14, 2005 Page 57 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
SQ48T/S15012 (1.2 Volt Out)
Fig. 1.2V.15: Input reflected ripple current, ic
(100 mA/div.), measured at input terminals at full rated
load current and Vin = 48 V. Refer to Fig. 1.2V.14 for
test setup. Time scale: 1 µs/div.
520
Iout [Adc]
Vout [Vdc]
0
0
10 15
1.5
1.0
0.5
Fig. 1.2V.17: Output voltage vs. load current showing
current limit point and converter shutdown point. Input
voltage has almost no effect on current limit
characteristic.
Fig. 1.2V.16: Input reflected ripple current, is
(10 mA/div.), measured through 10 µH at the source at
full rated load current and Vin = 48 V. Refer to
Fig. 1.2V.14 for test setup. Time scale: 1 µs/div.
Fig. 1.2V.18: Load current (top trace, 20 A/div.,
20 ms/div.) into a 10 m short circuit during restart, at
Vin = 48 V. Bottom trace (20 A/div., 1 ms/div.) is an
expansion of the on-time portion of the top trace.
REV. SEP 14, 2005 Page 58 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
Electrical Specifications: SQ48T/S15010 (1.0 Volt Out)
Conditions: TA = 25 ºC, Airflow = 300 LFM (1.5 m/s), Vin = 48 VDC, Vout = 1.0 VDC, unless otherwise specified.
Parameter Notes Min Typ Max Units
Input Characteristics
Maximum Input Current 15 ADC, 1.0 VDC Out @ 36 VDC In 0.52
ADC
Input Stand-by Current Vin = 48 V, converter disabled 3
mADC
Input No Load Current (0 load on the output) Vin = 48 V, converter enabled 22
mADC
Input Reflected-Ripple Current 25 MHz bandwidth 7.5
mAPK-PK
Input Voltage Ripple Rejection 120 Hz TBD dB
Output Characteristics
Output Voltage Set Point (no load) 0.990 1.000 1.010 VDC
Output Regulation
Over Line ±1 ±2
mV
Over Load ±1 ±3
mV
Output Voltage Range Over line, load and temperature1 0.985 1.015
VDC
Output Ripple and Noise - 25 MHz
bandwidth
Full load + 10 µF tantalum + 1 µF
ceramic 30 50
mVPK-PK
External Load Capacitance Plus full load (resistive) 15,000
µF
Output Current Range 0 15
ADC
Current Limit Inception Non-latching 15.75 18 20 ADC
Peak Short-Circuit Current Non-latching, Short =10 m. 30 40
A
RMS Short-Circuit Current Non-latching 5.3
Arms
Dynamic Response
Load Change 25% of Iout Max, di/dt = 0.1 A/µs Co = 1 µF ceramic 80
mV
di/dt = 5 A/µs Co = 450 µF tantalum + 1 µF ceramic 140 mV
Settling Time to 1% 100 µs
Efficiency
100% Load 80.5 %
50% Load 81.0 %
1 -40 ºC to 85 ºC.
Ambient Temperature [°C]
20 30 40 50 60 70 80 90
Load Current [Adc]
0
5
10
15
20
500 LFM (2.5 m/s)
400 LFM (2.0 m/s)
300 LFM (1.5 m/s)
200 LFM (1.0 m/s)
100 LFM (0.5 m/s)
30 LFM (0.15 m/s)
Fig. 1.0V.1: Available load current vs. ambient air
temperature and airflow rates for SQ48T15010 converter
with D height pins mounted vertically with Vin = 48 V, air
flowing from pin 3 to pin 1, and maximum FET
temperature ≤ 120 °C.
Ambient Temperature [°C]
20 30 40 50 60 70 80 90
Load Current [Adc]
0
5
10
15
20
500 LFM (2.5 m/s)
400 LFM (2.0 m/s)
300 LFM (1.5 m/s)
200 LFM (1.0 m/s)
100 LFM (0.5 m/s)
30 LFM (0.15 m/s)
Fig. 1.0V.2: Available load current vs. ambient air
temperature and airflow rates for SQ48T15010 converter
with D height pins mounted horizontally with Vin = 48 V,
air flowing from pin 3 to pin 1, and maximum FET
temperature ≤ 120 °C.
REV. SEP 14, 2005 Page 59 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
SQ48T/S15010 (1.0 Volt Out)
Ambient Temperature [°C]
20 30 40 50 60 70 80 90
Load Current [Adc]
0
5
10
15
20
500 LFM (2.5 m/s)
400 LFM (2.0 m/s)
300 LFM (1.5 m/s)
200 LFM (1.0 m/s)
100 LFM (0.5 m/s)
30 LFM (0.15 m/s)
Fig. 1.0V.3: Available load current vs. ambient air
temperature and airflow rates for SQ48S15010 converter
mounted vertically with Vin = 48 V, air flowing from pin 3
to pin 1, and maximum FET temperature ≤ 120 °C.
Load Current [Adc]
0246810121416
Efficiency
0.60
0.65
0.70
0.75
0.80
0.85
0.90
72 V
48 V
36 V
Fig. 1.0V.5: Efficiency vs. load current and input voltage for
SQ48T/S15010 converter mounted vertically with air
flowing from pin 3 to pin 1 at a rate of 300 LFM (1.5 m/s)
and Ta = 25 °C.
Ambient Temperature [°C]
20 30 40 50 60 70 80 90
Load Current [Adc]
0
5
10
15
20
500 LFM (2.5 m/s)
400 LFM (2.0 m/s)
300 LFM (1.5 m/s)
200 LFM (1.0 m/s)
100 LFM (0.5 m/s)
30 LFM (0.15 m/s)
Fig. 1.0V.4: Available load current vs. ambient air
temperature and airflow rates for SQ48S15010 converter
mounted horizontally with Vin = 48 V, air flowing from pin
3 to pin 1, and maximum FET temperature ≤ 120 °C.
Load Current [Adc]
0246810121416
Efficiency
0.60
0.65
0.70
0.75
0.80
0.85
0.90
70 C
55 C
40 C
Fig. 1.0V.6: Efficiency vs. load current and ambient
temperature for SQ48T/S15010 converter mounted
vertically with Vin = 48 V and air flowing from pin 3 to pin
1 at a rate of 200 LFM (1.0 m/s).
REV. SEP 14, 2005 Page 60 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
SQ48T/S15010 (1.0 Volt Out)
Load Current [Adc]
0246810121416
Power Dissipation [W]
0.00
1.00
2.00
3.00
4.00
5.00
72 V
48 V
36 V
Fig. 1.0V.7: Power dissipation vs. load current and
input voltage for SQ48T/S15010 converter mounted
vertically with air flowing from pin 3 to pin 1 at a rate of
300 LFM (1.5 m/s) and Ta = 25 °C.
Fig. 1.0V.9: Turn-on transient at full rated load current
(resistive) with no output capacitor at Vin = 48 V,
triggered via ON/OFF pin. Top trace: ON/OFF signal
(5 V/div.). Bottom trace: output voltage (0.5 V/div.). Time
scale: 2 ms/div.
Load Current [Adc]
0246810121416
Power Dissipation [W]
0.00
1.00
2.00
3.00
4.00
5.00
70 C
55 C
40 C
Fig. 1.0V.8: Power dissipation vs. load current and
ambient temperature for SQ48T/S15010 converter
mounted vertically with Vin = 48 V and air flowing from
pin 3 to pin 1 at a rate of 200 LFM (1.0 m/s).
Fig. 1.0V.10: Turn-on transient at full rated load
current (resistive) plus 10,000 µF at Vin = 48 V,
triggered via ON/OFF pin. Top trace: ON/OFF signal
(5 V/div.). Bottom trace: output voltage (0.5 V/div.).
Time scale: 2 ms/div.
REV. SEP 14, 2005 Page 61 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
SQ48T/S15010 (1.0 Volt Out)
Fig. 1.0V.11: Output voltage response to load current
step-change (3.75 A – 7.5 A – 3.75 A) at Vin = 48 V.
Top trace: output voltage (100 mV/div.). Bottom trace:
load current (5 A/div.). Current slew rate: 0.1 A/µs.
Co = 1 µF ceramic. Time scale: 0.2 ms/div.
Fig. 1.0V.13: Output voltage ripple (20 mV/div.) at full
rated load current into a resistive load with Co = 10 µF
tantalum + 1 µF ceramic and Vin = 48 V. Time scale:
1 µs/div.
Fig. 1.0V.12: Output voltage response to load current
step-change (3.75 A – 7.5 A – 3.75 A) at Vin = 48 V.
Top trace: output voltage (100 mV/div.). Bottom trace:
load current (5 A/div.). Current slew rate: 5 A/µs. Co =
450 µF tantalum + 1 µF ceramic. Time scale: 0.2 ms/div.
Vout
Vsource
iSiC
1 µF
ceramic
capacitor
10 µH
source
inductance SemiQTM Family
DC-DC
Converter
33 µF
ESR <1
electrolytic
capacitor
Ω
Fig. 1.0V.14: Test Setup for measuring input reflected
ripple currents, ic and is.
REV. SEP 14, 2005 Page 62 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
SQ48T/S15010 (1.0 Volt Out)
Fig. 1.0V.15: Input reflected ripple current, ic
(100 mA/div.), measured at input terminals at full rated
load current and Vin = 48 V. Refer to Fig. 1.0V.14 for
test setup. Time scale: 1 µs/div.
520
Iout [Adc]
Vout [Vdc]
0
0
10 15
1.5
1.0
0.5
Fig. 1.0V.17: Output voltage vs. load current showing
current limit point and converter shutdown point. Input
voltage has almost no effect on current limit
characteristic.
Fig. 1.0V.16: Input reflected ripple current, is
(10 mA/div.), measured through 10 µH at the source at
full rated load current and Vin = 48 V. Refer to
Fig. 1.0V.14 for test setup. Time scale: 1 µs/div.
Fig. 1.0V.18: Load current (top trace, 20 A/div.,
20 ms/div.) into a 10 m short circuit during restart, at
Vin = 48 V. Bottom trace (20 A/div., 1 ms/div.) is an
expansion of the on-time portion of the top trace.
REV. SEP 14, 2005 Page 63 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
Physical Information
TOP VIEW
1
2
3
7
8
6
5
4
SIDE VIEW
SQ48S Pinout (Surface Mount)
SIDE VIEW
TOP VIEW
1
2
3
7
8
6
5
4
SQ48T Pinout (Through-hole)
Pad/Pin Connections
Pad/Pin # Function
1 Vin (+)
2 ON/OFF
3 Vin (-)
4 Vout (-)
5 SENSE(-)
6 TRIM
7 SENSE(+)
8 Vout (+)
HT
(
Max. Hei
g
ht
)
CL
(
Min. Clea
r
ance
)
Height
Option +0.000 [+0.00]
-0.038 [- 0.97]
+0.016 [+0.41]
-0.000 [- 0.00]
A 0.303 [7.69] 0.030 [0.77]
B 0.336 [8.53] 0.063 [1.60]
C 0.500 [12.70] 0.227 [5.77]
D 0.400 [10.16] 0.127 [3.23]
E 0.282 [7.16] 0.009 [0.23]
PL
Pin Len
g
th
Pin
Option ±0.005 [±0.13]
A 0.188 [4.77]
B 0.145 [3.68]
C 0.110 [2.79]
SQ48T Platform Notes
• All dimensions are in inches [mm]
• Pins 1-3 and 5-7 are Ø 0.040” [1.02]
with Ø 0.078” [1.98] shoulder
• Pins 4 and 8 are Ø 0.062” [1.57]
without shoulder
• Pin material: Brass
• Pin Finish: Tin/Lead over Nickel or
Matte Tin over Nickel for “G” version
• Converter Weight: 0.53 oz [15 g]
SQ48S Platform Notes
• All dimensions are in inches [mm]
• Connector Material: Copper
• Connector Finish: Gold over Nickel
• Converter Weight: 0.66 oz [18.5 g]
• Recommended Surface-Mount Pads:
Min. 0.080” X 0.112” [2.03 x 2.84]
Max. 0.092” X 0.124” [2.34 x 3.15]
REV. SEP 14, 2005 Page 64 of 64 www.power-one.com
SQ48 DC-DC Series Data Sheet
36-75 VDC Input; 1.0-12 VDC Output
Converter Part Numbering Ordering Information
Product
Series
Input
Voltage
Mounting
Scheme
Rated Load
Current
Output
Voltage ON/OFF
Logic
Maximum
Height [HT]
Pin
Length
[PL]
Special
Features
Environ-
mental
SQ 48 T 15 012 - N B A 0
One-
Eighth
Brick
Format
36-75 V
S ⇒
Surface
Mount
T⇒
Through-
hole
15 ⇒ 15 A
(1.0 - 3.3 V)
10 ⇒ 10 A
(5.0 V)
08 ⇒ 8 A
(6.0 V)
05 ⇒ 5.3 A
(8.0 V)
04 ⇒ 4 A
(12.0 V)
010 ⇒ 1.0 V
012 ⇒ 1.2 V
015 ⇒ 1.5 V
018 ⇒ 1.8 V
020 ⇒ 2.0 V
025 ⇒ 2.5 V
033 ⇒ 3.3 V
050 ⇒ 5.0 V
060 ⇒ 6.0 V
080 ⇒ 8.0 V
120 ⇒ 12.0 V
N ⇒
Negative
P ⇒
Positive
SMT
S ⇒ 0.273”
Through
hole
A ⇒ 0.303”
B ⇒ 0.336”
C ⇒ 0.500”
D ⇒ 0.400”
E ⇒ 0.282”
SMT
0 ⇒ 0.00”
Through
hole
A ⇒ 0.188”
B ⇒ 0.145”
C ⇒ 0.110”
0 ⇒ STD
T ⇒
Alternative
Trim
Option
(For 1.2 V,
1.0 V only)
G ⇒ RoHS
Compliant
with Pb
free solder
The example above describes P/N SQ48T15012-NBA0: 36-75 V input, through-hole mounting, 15 A @ 1.2 V output, negative ON/OFF logic,
a maximum height of 0.336”, a through the board pin length of 0.188”, standard trim equations, and Eutectic Tin/Lead solder1. Please consult
factory for the complete list of available options.
1 The solder exemption is for customers choosing to use the exemptions for lead in solders for servers, storage and storage array systems,
and network infrastructure equipment for switching, signaling, transmission, and network management for telecommunications.
NUCLEAR AND MEDICAL APPLICATIONS - Power-One products are not designed, intended for use in, or authorized for use as critical
components in life support systems, equipment used in hazardous environments, or nuclear control systems without the express written
consent of the respective divisional president of Power-One, Inc.
TECHNICAL REVISIONS - The appearance of products, including safety agency certifications pictured on labels, may change depending on
the date manufactured. Specifications are subject to change without notice.
