T
Technical
echnical
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Specification
pecification
IQ18050QT
IQ18050QTA20
A20
Product # IQ18050QTA20 Phone 1-888-567-9596 www.synqor.com Doc.# 005-I805020 Rev. C 9/14/07 Page 1
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• High efficiency, >81% at full rated load current
• Delivers up to 20 amps of output current (100W) with
minimal derating - no heatsink required
• Wide operating input voltage range: 9V – 36V
• Fixed frequency switching provides predictable EMI per-
formance
•No minimum load requirement means no preload resis-
tors required
Operational Features
Operational Features
•Input under-voltage lockout disables converter at low
input voltage conditions
• Output current limit and short circuit protection protects
converter and load from permanent damage and conse-
quent hazardous conditions
• Active back bias limit prevents damage to converter
from external load induced pre-bias
• Output over-voltage protection protects load from dam-
aging voltages
• Thermal shutdown protects converter from abnormal
environmental conditions
Pr
Protection Features
otection Features
• 2250V, 30 MWinput-to-output isolation provides
input/output ground separation
• UL/cUL 60950-1 recognized (US & Canada), basic
insulation rating (pending)
• TUV certified to EN60950-1 (pending)
• Meets 72/23/EEC and 93/68/EEC directives which
facilitates CE Marking in user’s end product
• Board and plastic components meet UL94V-0 flammabil-
ity requirements
Safety Features
Safety Features
•Industry standard quarter-brick pin-out configuration
• Industry standard size: 1.45” x 2.3” (36.8x58.4mm)
• Total open frame height less than 0.43” (10.9mm), per-
mits better airflow and smaller card pitch
• Total open frame weight: 1.5 oz. (42 grams)
• Flanged pins designed to permit surface mount soldering
(allowing to avoid wave solder) using FPiP technique
Mechanical Features
Mechanical Features
• On/Off control referenced to input side
• Remote sense for the output voltage compensates for
output distribution drops
• Output voltage trim permits custom voltages and voltage
margining
Contr
Control Features
ol Features
Open Frame
Encased
12/24V
12/24Vin
in 5.0V
5.0Vout
out 20Amp
20Amp 2250Vdc
2250Vdc Quar
Quarter-brick
ter-brick
Input
Input Output
Output Current
Current Isolation
Isolation DC/DC Conver
DC/DC Converter
ter
Product # IQ18050QTA20 Phone 1-888-567-9596 www.synqor.com Doc.# 005-I805020 Rev. C 9/14/07 Page 2
T
Technical S
echnical S pecification
pecification
Input:
Input:
Output:
Output:
Current:
Current:
P
Package:
ackage:
9-36 V
9-36 V
5.0 V
5.0 V
20 A
20 A
Quarter-brick
Quarter-brick
ParameterPMin. Typ. Max. Units Notes & Conditions
ABSOLUTE MAXIMUM RATINGS
Input Voltage
Non-Operating 40 V Continuous
Operating 36 V Continuous
Isolation Voltage Basic insulation, Pollution Degree 2
Input to Output 2250 Vdc
Input to Base-Plate 2250 Vdc
Output to Base-Plate 2250 Vdc
Operating Temperature -40 100 °C
Storage Temperature -55 125 °C
Voltage at ON/OFF input pin -2 18 V
INPUT CHARACTERISTICS
Operating Input Voltage Range 9 18 36 V 40V transient for 100ms; see Note 1
Input Under-Voltage Lockout
Turn-On Voltage Threshold 10.0 10.3 10.5 V
Turn-Off Voltage Threshold 8.0 8.3 8.6 V
Lockout Voltage Hysteresis 2 V
Maximum Input Current 18.1 A 9 Vin, trim up, in current limit
No-Load Input Current 184 230 mA
Disabled Input Current 2.6 6.0 mA
Response to Input Transient 0.2 V 300V/ms input transient
Input Terminal Ripple Current 366 mA RMS
Recommended Input Fuse 30 A Fast acting external fuse recommended
Input Filter Component Values (L\C) 0.47\18 µH\µF Internal values; see Figure E
Recommended External Input Capacitance 470 µF Typical ESR 0.1-0.2W
OUTPUT CHARACTERISTICS
Output Voltage Set Point 4.950 5.000 5.050 V
Output Voltage Regulation
Over Line +0.1 +0.3 %
Over Load +0.1 +0.3 %
Over Temperature -75 75 mV
Total Output Voltage Range 4.875 5.125 VOver sample, line, load, temperature & life
Output Voltage Ripple and Noise 20MHz bandwidth; see note 2
Peak-to-Peak 68 140 mV Full Load
RMS 10.0 20.0 mV Full Load
Operating Output Current Range 0 20 A Subject to thermal derating
Output DC Current-Limit Inception 22 24 26 A Output Voltage 10% Low
Output DC Current-Limit Shutdown Voltage 2.3 V
Back-Drive Current Limit while Enabled 0.6 A Negative current drawn from output
Back-Drive Current Limit while Disabled 0 15 50 mA Negative current drawn from output
Maximum Output Capacitance 8,000 µF Vout nominal at full load (resistive load)
DYNAMIC CHARACTERISTICS
Output Voltage during Load Current Transient
For a Step Change in Output Current (0.1A/µs) 120 mV 50% to 75% to 50% Iout max
Settling Time 100 µs To within 1% Vout nom
Turn-On Transient
Turn-On Time 9 ms Full load, Vout=90% nom.
Start-Up Inhibit Time 200 230 250 ms -40°C to +125°C; Figure F
Output Voltage Overshoot 0 % 10,000 µF load capacitance, Iout = 0A
EFFICIENCY
100% Load 88.4 % See Figure 1 for efficiency curve
50% Load 89.7 % See Figure 1 for efficiency curve
ISOLATION CHARACTERISTICS
Isolation Voltage (dielectric strength)
Input to Output 2250 Vdc
Input to Base-Plate 2250 Vdc
Output to Base-Plate 2250 Vdc
Isolation Resistance 30 MW
Isolation Capacitance (input to output) 1,000 pF See note 3
IQ18050QTA20 ELECTRICAL CHARACTERISTICS
TA=25°C, airflow rate=300 LFM, Vin=18Vdc unless otherwise noted; full operating temperature range is -40°C to +100°C ambient
temperature with appropriate power derating.
Specifications subject to change without notice.
Note 1: Start-up guaranteed above 10.5V, but will operate down to 9V.
Note 2: Output is terminated with 1 µF ceramic and 15 µF low-ESR tantalum capacitors (only 1µF ceramic for Vout > 18 V).
Note 3: Higher values of isolation capacitance can be added external to the module.
Product # IQ18050QTA20 Phone 1-888-567-9596 www.synqor.com Doc.# 005-I805020 Rev. C 9/14/07 Page 3
T
Technical S
echnical S pecification
pecification
Input:
Input:
Output:
Output:
Current:
Current:
P
Package:
ackage:
9-36 V
9-36 V
5.0 V
5.0 V
20 A
20 A
Quarter-brick
Quarter-brick
ParameterPMin. Typ. Max. Units Notes & Conditions
TEMPERATURE LIMITS FOR POWER DERATING CURVES
Semiconductor Junction Temperature 125 °C Package rated to 150°C
Board Temperature 125 °C UL rated max operating temp 130°C
Transformer Temperature 125 °C See Figure 3 for derating curve
Maximum Baseplate Temperature, TB100 °C Applies to baseplated and encased units only
FEATURE CHARACTERISTICS
Switching Frequency 230 250 270 kHz Regulation and Isolation stages
ON/OFF Control
Off-State Voltage 2.4 18 V
On-State Voltage -2 0.8 V
ON/OFF Control Figures A & B
Pull-Up Voltage 5 V
Pull-Up Resistance 50 kW
Output Voltage Trim Range -20 +10 % Measured across Pins 8 & 4; Figure C
Output Voltage Remote Sense Range +10 % Measured across Pins 8 & 4
Output Over-Voltage Protection 117 122 127 % Over full temp range; % of nominal Vout
Over-Temperature Shutdown 125 °C Average PCB Temperature
Over-Temperature Shutdown Restart Hysteresis 10 °C
Load Current Scale Factor 1000 See Output Load Current app. note on our web
RELIABILITY CHARACTERISTICS
Calculated MTBF (Telcordia) 2.5 106Hrs. TR-NWT-000332; 80% load,300LFM, 40oC Ta
Calculated MTBF (MIL-217) 1.8 106Hrs. MIL-HDBK-217F; 80% load, 300LFM, 40oC Ta
Field Demonstrated MTBF 106Hrs. See our website for details
STANDARDS COMPLIANCE
ParameterPNotes
STANDARDS COMPLIANCE
UL/cUL 60950-1 File # E194341, Basic insulation & pollution degree 2
EN60950-1 Certified by TUV
72/23/EEC
93/68/EEC
Needle Flame Test (IEC 695-2-2) Test on entire assembly; board & plastic components UL94V-0 compliant
IEC 61000-4-2 ESD test, 8kV - NP, 15kV air - NP (Normal Performance)
GR-1089-CORE Section 7 - electrical safety, Section 9 - bonding/grounding
Telcordia (Bellcore) GR-513
• An external input fuse must always be used to meet these safety requirements. Contact SynQor for official safety
certificates on new releases or download from the SynQor website.
ELECTRICAL CHARACTERISTICS (Continued)
OPTIONS
SynQor provides various options for Pin Length and Feature Set for
this family of Power Interface Modules. Please consult the last page
for information on available options.
PATENTS
SynQor is protected under various patents. Please consult the last
page for further information.
Product # IQ18050QTA20 Phone 1-888-567-9596 www.synqor.com Doc.# 005-I805020 Rev. C 9/14/07 Page 4
T
Technical S
echnical S pecification
pecification
Input:
Input:
Output:
Output:
Current:
Current:
P
Package:
ackage:
9-36 V
9-36 V
5.0 V
5.0 V
20 A
20 A
Quarter-brick
Quarter-brick
0
2
4
6
8
10
12
14
16
0 5 10 15 20
Load Curr ent (A)
Power Dissipation (W)
9 V in
18 V in
36 Vin
60
65
70
75
80
85
90
95
100
0 5 10 15 20
Load Curr ent (A)
Efficiency (%)
9 V in
18 V in
36 V in
Figure 1: Efficiency at nominal output voltage vs. load current for min-
imum, nominal, and maximum input voltage at 25
°
C. Figure 2: Power dissipation at nominal output voltage vs. load current
for minimum, nominal, and maximum input voltage at 25
°
C.
Ambient Ai r Temperature (°C)
Iout (A)
400 LFM (2.0 m/s)
300 LFM (1.5 m/s)
200 LFM (1.0 m/s)
100 LFM (0.5 m/s)
Figure 3: Open frame converter maximum output power derating vs.
ambient air temperature for airflow rates of 100 LFM through 400 LFM.
Air flows across the converter from pin 3 to pin 1 (nominal input voltage).
Figure 4: Open frame converter thermal plot at 35.2 amp load current
(63.4 W) with 55
°
C air flowing at the rate of 200 LFM. Air flows across
the converter from pin 3 to pin 1 (nominal input voltage).
A mbi ent Air Temper at ure ( ° C)
Iout (A)
400 LFM (2.0 m/s)
300 LFM (1.5 m/s)
200 LFM (1.0 m/s)
100 LFM (0.5 m/s)
Ambient Ai r Temperature (°C)
Iout (A)
400 LFM (2.0 m/s)
300 LFM (1.5 m/s)
200 LFM (1.0 m/s)
100 LFM (0.5 m/s)
Figure 5: Base-plated converter (without heatsink) max. output power derating
vs. ambient air temperatur e for airflow rates of 100 LFM thr ough 400 LFM. Air
flows acr oss the converter fr om pin 3 to pin 1 (nominal input voltage, TB=100ºC).
Figure 6: Base-plated converter (with 1/2” heatsink) max. output power derating
vs. ambient air temperatur e for airflow rates of 100 LFM thr ough 400 LFM. Air
flows acr oss the converter fr om pin 3 to pin 1 (nominal input voltage, TB=100ºC).
Semiconductor junction temperature is
within 1
°
C of surface temperature
Product # IQ18050QTA20 Phone 1-888-567-9596 www.synqor.com Doc.# 005-I805020 Rev. C 9/14/07 Page 5
T
Technical S
echnical S pecification
pecification
Input:
Input:
Output:
Output:
Current:
Current:
P
Package:
ackage:
9-36 V
9-36 V
5.0 V
5.0 V
20 A
20 A
Quarter-brick
Quarter-brick
Figure 7: Output voltage response to step-change in load current (50%-75%-50%
of Iout(max); dI/dt = 0.1 A/
µ
s). Load cap: 1
µ
F ceramic cap. Ch 1: Vout (200
mV/div), Ch 2: Iout (5 A/div).
Figure 8: Output voltage response to step-change in input voltage
(300 V/ms). Load cap: 100
µ
F, electrolytic output capacitance. Ch 1: Vout
(200 mV/div), Ch 2: Vin (10 V/div).
0
1
2
3
4
5
6
0 5 10 15 20 25
Load Curr ent (A)
Output Voltage (V)
9 V in
18 V in
36 V in
Figure 9: Turn-on transient at full load (resistive load) (2 ms/div).
Input voltage pre-applied. Ch 1: Vout (2 V/div). Ch 2: ON/OFF input
(2 V/div).
Figure 10: Output voltage vs. load current showing typical current limit
curves and converter shutdown points.
Product # IQ18050QTA20 Phone 1-888-567-9596 www.synqor.com Doc.# 005-I805020 Rev. C 9/14/07 Page 6
T
Technical S
echnical S pecification
pecification
Input:
Input:
Output:
Output:
Current:
Current:
P
Package:
ackage:
9-36 V
9-36 V
5.0 V
5.0 V
20 A
20 A
Quarter-brick
Quarter-brick
BASIC OPERATION AND FEATURES
The InQor series converter uses a two-stage power conversion
topology. The first stage is a buck-converter that keeps the output
voltage constant over variations in line, load, and temperature.
The second stage uses a transformer to provide the functions of
input/output isolation and voltage step-up or step-down to
achieve the output voltage required.
Both the first stage and the second stage switch at a fixed fre-
quency for predictable EMI performance. Rectification of the
transformer’s output is accomplished with synchronous rectifiers.
These devices, which are MOSFETs with a very low on-state resis-
tance, dissipate far less energy than Schottky diodes. This is the
primary reason that the InQor converter has such high efficiency,
even at very low output voltages and very high output currents.
Dissipation throughout the converter is so low that it does not
require a heatsink for operation in many applications. Since a
heatsink is not required, the InQor converter does not need a
metal baseplate or potting material to help conduct the dissipat-
ed energy to the heatsink. The InQor converter can thus be built
more simply and reliably using high yield surface mount tech-
niques on a PCB substrate.
Nevertheless, for those thermally demanding applications that
require heatsinks or cold-plate mounting, an optional base-plated
version of the InQor is available. In addition, for applications
having a harsh environment, a totally encased and base-plated
version is also available.
The InQor series of half-brick and quarter-brick converters uses
the industry standard footprint and pin-out configuration.
CONTROL FEATURES
REMOTE ON/OFF (Pin 2): The ON/OFF input, Pin 2, permits
the user to control when the converter is on or off. This input is
referenced to the return terminal of the input bus, Vin(-). The
ON/OFF signal is active low (meaning that a low turns the con-
verter on). Figure A details four possible circuits for driving the
ON/OFF pin. Figure B is a detailed look of the internal ON/OFF
circuitry.
REMOTE SENSE(+) (Pins 7 and 5): The SENSE(+) inputs cor-
rect for voltage drops along the conductors that connect the con-
verter’s output pins to the load.
Pin 7 should be connected to Vout(+) and Pin 5 should be con-
nected to Vout(-) at the point on the board where regulation is
desired. A remote connection at the load can adjust for a voltage
drop only as large as that specified in this datasheet, that is
[Vout(+) - Vout(-)]– [Vsense(+) - Vsense(-)]<
Sense Range % x Vout
Pins 7 and 5 must be connected for proper regulation of the out-
put voltage. If these connections are not made, the converter will
deliver an output voltage that is slightly higher than its specified
value.
Note: the output over-voltage protection circuit senses the voltage
across the output (pins 8 and 4) to determine when it should trig-
ger, not the voltage across the converter’s sense leads (pins 7
and 5). Therefore, the resistive drop on the board should be
small enough so that output OVP does not trigger, even during
load transients.
Open Collector Enable Circuit
Figure A: Various circuits for driving the ON/OFF pin. Figure B: Internal ON/OFF pin circuitry
Remote Enable Circuit
Direct Logic Drive
Negative Logic
(Permanently Enabled)
ON/OFF
Vin(_)
ON/OFF
ON/OFF
Vin(_)
ON/OFF
5V
TTL/
CMOS
Vin(_)
Vin(_)
TTL
5V
50k
50k
ON/OFF
Vin(_)
100pF
Product # IQ18050QTA20 Phone 1-888-567-9596 www.synqor.com Doc.# 005-I805020 Rev. C 9/14/07 Page 7
T
Technical S
echnical S pecification
pecification
Input:
Input:
Output:
Output:
Current:
Current:
P
Package:
ackage:
9-36 V
9-36 V
5.0 V
5.0 V
20 A
20 A
Quarter-brick
Quarter-brick
OUTPUT VOLTAGE TRIM (Pin 6): The TRIM input permits the
user to adjust the output voltage across the sense leads up or
down according to the trim range specifications.
To decrease the output voltage, the user should connect a resistor
between Pin 6 and Pin 5 (SENSE(-) input). For a desired decrease
of the nominal output voltage, the value of the resistor should be
Rtrim-down =
(
511
)
- 10.22 (kW)
D%
where
D% =Vnominal – Vdesired x100%
Vnominal
To increase the output voltage, the user should connect a resistor
between Pin 6 and Pin 7 (SENSE(+) input). For a desired increase
of the nominal output voltage, the value of the resistor should be
Figure C graphs the relationship between the trim resistor value
and Rtrim-up and Rtrim-down, showing the total range the output
voltage can be trimmed up or down.
Figure C: Trim Graph
Note: the TRIM feature does not affect the voltage at which the
output over-voltage protection circuit is triggered. Trimming the
output voltage too high may cause the over-voltage protection cir-
cuit to engage, particularly during transients.
It is not necessary for the user to add capacitance at the Trim pin.
The node is internally bypassed to eliminate noise.
Total DC Variation of Vout: For the converter to meet its full
specifications, the maximum variation of the DC value of Vout,
due to both trimming and remote load voltage drops, should not
be greater than that specified for the output voltage trim range.
PROTECTION FEATURES
Input Under-Voltage Lockout: The converter is designed to
turn off when the input voltage is too low, helping avoid an input
system instability problem, described in more detail in the appli-
cation note titled “Input System Instability”. The lockout circuitry
is a comparator with DC hysteresis. When the input voltage is ris-
ing, it must exceed the typical Turn-On Voltage Threshold value
(listed on the specifications page) before the converter will turn
on. Once the converter is on, the input voltage must fall below
the typical Turn-Off Voltage Threshold value before the converter
will turn off.
Output Current Limit: The maximum current limit remains con-
stant as the output voltage drops. However, once the impedance
of the short across the output is small enough to make the output
voltage drop below the specified Output DC Current-Limit
Shutdown Voltage, the converter turns off.
The converter then enters a “hiccup mode” where it repeatedly
turns on and off at a 5 Hz (nominal) frequency with a 5% duty
cycle until the short circuit condition is removed. This prevents
excessive heating of the converter or the load board.
Output Over-Voltage Limit: If the voltage across the output
pins exceeds the Output Over-Voltage Protection threshold, the
converter will immediately stop switching. This prevents damage
to the load circuit due to 1) excessive series resistance in output
current path from converter output pins to sense point, 2) a
release of a short-circuit condition, or 3) a release of a current
limit condition. Load capacitance determines exactly how high
the output voltage will rise in response to these conditions. After
200 ms the converter will automatically restart.
Over-Temperature Shutdown: A temperature sensor on the
converter senses the average temperature of the module. The
thermal shutdown circuit is designed to turn the converter off
when the temperature at the sensed location reaches the Over-
Temperature Shutdown value. It will allow the converter to turn on
again when the temperature of the sensed location falls by the
amount of the Over-Temperature Shutdown Restart Hysteresis
value.
Rtrim-up
(k
W)
)
where VOUT = Nominal Output Voltage
= (
_511 _10.22
5.11VOUT(100+
D%)
1.225D%D%
10.0
100.0
1,000.0
10,000.0
100,000.0
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
Trim Resistance (kOhms)
% Incr ea se in Vout % Decrease in Vout
Product # IQ18050QTA20 Phone 1-888-567-9596 www.synqor.com Doc.# 005-I805020 Rev. C 9/14/07 Page 8
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Input:
Input:
Output:
Output:
Current:
Current:
P
Package:
ackage:
9-36 V
9-36 V
5.0 V
5.0 V
20 A
20 A
Quarter-brick
Quarter-brick
APPLICATION CONSIDERATIONS
Input System Instability: This
condition can occur because
any DC/DC converter appears incrementally as a negative
resistance load. A detailed application note titled “Input
System Instability” is available on the SynQor website which
provides an understanding of why this instability arises, and
shows the preferred solution for correcting it.
Application Circuits: Figure D provides a typical circuit dia-
gram which details the input filtering and voltage trimming.
Input Filtering and External Capacitance: Figure E pro-
vides a diagram showing the internal input filter components.
This filter dramatically reduces input terminal ripple current,
which otherwise could exceed the rating of an external elec-
trolytic input capacitor. The recommended external input capac-
itance is specified in the Input Characteristics section on the
Electrical Specifications page. More detailed information is
available in the application note titled “EMI Characteristics” on
the SynQor website.
Startup Inhibit Period: The Startup Inhibit Period ensures that
the converter will remain off for approximately 200ms when it is
shut down for any reason. When an output short is present, this
generates a 5Hz "hiccup mode," which prevents the converter
from overheating. In all, there are seven ways that the converter
can be shut down, initiating a Startup Inhibit Period:
• Input Under-Voltage Lockout
• Input Over-Voltage Shutdown (not present in Quarter-brick)
• Output Over-Voltage Protection
• Over Temperature Shutdown
• Current Limit
• Short Circuit Protection
• Turned off by the ON/OFF input
Figure F shows three turn-on scenarios, where a Startup Inhibit
Period is initiated at t0, t1, and t2:
Before time t0, when the input voltage is below the UVL threshold,
the unit is disabled by the Input Under-Voltage Lockout feature.
When the input voltage rises above the UVL threshold, the Input
Under-Voltage Lockout is released, and a Startup Inhibit Period is
initiated. At the end of this delay, the ON/OFF pin is evaluated,
and since it is active, the unit turns on.
Vin External
Input
Filter
Trim
Vin(+)
Iload
Cload
L
Vout(+)
Rtrim-up
or
Rtrim-down
Vsense(+)
ON/OFF
Vin(_)
Vin(+)
Vin(_)
Vout(_)
Vsense(_)
Electrolytic
Capacitor
Figure D: Typical application circuit (negative logic unit, permanently enabled).
Figure E: Internal Input Filter Diagram (component values listed on the specifications page).
C
Product # IQ18050QTA20 Phone 1-888-567-9596 www.synqor.com Doc.# 005-I805020 Rev. C 9/14/07 Page 9
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Technical S
echnical S pecification
pecification
Input:
Input:
Output:
Output:
Current:
Current:
P
Package:
ackage:
9-36 V
9-36 V
5.0 V
5.0 V
20 A
20 A
Quarter-brick
Quarter-brick
At time t1, the unit is disabled by the ON/OFF pin, and it cannot
be enabled again until the Startup Inhibit Period has elapsed.
When the ON/OFF pin goes high after t2, the Startup Inhibit
Period has elapsed, and the output turns on within the typical
Turn-On Time.
An optional base-plated version is available for applications that
require heatsinks, and an encased version is available for harsh
environments.
Thermal Considerations: Because the InQor series of con-
verters are so efficient, they don’t need a heatsink in many appli-
cations. Figure 3 shows a power derating curve of an open frame
converter for various ambient temperatures and airflow rates.
These curves represent a condition which results in a maximum
semiconductor junction temperature of 125ºC, which is comfort-
able below the 150ºC ratings of these components.
For those applications that are more demanding, or that require
a cold-plate mounting, the InQor converters may be purchased
with an optional base-plate. The maximum operating base-plate
temperature, TB, is 100ºC. As long as the user’s thermal system
keeps TB<100ºC, the converter can deliver its full rated power.
A power derating curve can be calculated for any heatsink that
is attached to the base-plate of the converter. It is only necessary
to determine the thermal resistance, RTHBA, of the chosen heatsink
between the base-plate and the ambient air for a given airflow
rate. This information is usually available from the heatsink ven-
dor. The following formula can the be used to determine the max-
imum power the converter can dissipate for a given thermal con-
dition if its base-plate is to be no higher than 100ºC.
Pdiss = 100ºC - TA
RTHBA
This value of power dissipation can then be used in conjunction
with the data shown in Figure 2 to determine the maximum load
current (and power) that the converter can deliver in the given
thermal condition.
For convenience, Figures 5 and 6 provide power derating curves
for a converter with a base-plate without a heatsink and with a
typical 1/2” high heatsink.
RoHS Compliance: The EU led RoHS (Restriction of Hazardous
Substances) Directive bans the use of Lead, Cadmium,
Hexavalent Chromium, Mercury, Polybrominated Biphenyls
(PBB), and Polybrominated Diphenyl Ether (PBDE) in Electrical
and Electronic Equipment. This SynQor product is 6/6 RoHS
compliant. For more information please refer to SynQor’s RoHS
addendum available at our RoHS Compliance / Lead Free
Initiative web page or e-mail us at rohs@synqor.com.
max
Under-Voltage
Lockout Turn-On
Threshold
ON/OFF
(neg logic)
Figure F: Startup Inhibit Period (turn-on time not to scale)
Vout
Vin
200ms 200ms
200ms
(typical start-up
inhibit period)
t0t1t2t
9ms (typical
turn on time)
ON ON ON
OFF OFF
Product # IQ18050QTA20 Phone 1-888-567-9596 www.synqor.com Doc.# 005-I805020 Rev. C 9/14/07 Page 10
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Technical S
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pecification
Input:
Input:
Output:
Output:
Current:
Current:
P
Package:
ackage:
9-36 V
9-36 V
5.0 V
5.0 V
20 A
20 A
Quarter-brick
Quarter-brick
Pin No. Name Function
1 Vin(+) Positive input voltage
2ON/OFF TTL input to turn converter
on and off, referenced to
Vin(-), with internal pull up.
3 Vin(–) Negative input voltage
4 Vout(–) Negative output voltage
5 SENSE(–) Negative remote sense1
6TRIM Output voltage trim2
7 SENSE(+) Positive remote sense3
8 Vout(+) Positive output voltage
Notes:
1. SENSE(–) should be connected to Vout(–) either remotely or at the converter.
2. Leave TRIM pin open for nominal output voltage.
3. SENSE(+) should be connected to Vout(+) either remotely or at the converter.
NOTES
1) Pins 1-3, 5-7 are 0.040” (1.02mm) diameter with 0.080” (2.03 mm) diameter
standoff shoulders.
2) Pins 4 and 8 are 0.062” (1.57 mm) diameter with 0.100” (2.54 mm) diame-
ter standoff shoulders.
3) Recommended pin length is 0.03” (0.76mm) greater than the PCB thickness.
4) All Pins: Material - Copper Alloy; Finish - Matte Tin over Nickel plate
5) Undimensioned components shown are for visual reference only.
6) Weight: Open frame: 1.5 oz. (42 g)
Base-plated: 2.5 oz. (69 g) typical
Encased: 3.02 oz. (85.7 g) typical
7) All dimensions in inches (mm)
Tolerances: x.xx +/-0.02 in. (x.x +/-0.5mm)
x.xxx +/-0.010 in. (x.xx +/-0.25mm)
8) Workmanship: Meets or exceeds IPC-A-610C Class II
9)
UL/TUV standards require a clearance greater than 0.04” (1.02mm)
between input and output for Basic insulation. This issue should be consid-
ered if any copper traces are on the top side of the user’s board. Note
that the ferrite cores are considered part of the input/primary circuit.
10) M3 screws used to bolt unit’s baseplate to other surfaces (such as a heatsink)
must not exceed 0.100” (2.54 mm) depth below the surface of the baseplate.
11) Applied torque per screw should not exceed 6in-lb. (0.7 Nm).
12) Baseplate flatness tolerance is 0.004” (.10mm) TIR for surface.
PIN DESIGNATIONS
MECHANICAL DIAGRAM
Open Frame
Product # IQ18050QTA20 Phone 1-888-567-9596 www.synqor.com Doc.# 005-I805020 Rev. C 9/14/07 Page 11
T
Technical S
echnical S pecification
pecification
Input:
Input:
Output:
Output:
Current:
Current:
P
Package:
ackage:
9-36 V
9-36 V
5.0 V
5.0 V
20 A
20 A
Quarter-brick
Quarter-brick
MECHANICAL DIAGRAM (continued)
Encased
Base-plated
Product # IQ18050QTA20 Phone 1-888-567-9596 www.synqor.com Doc.# 005-I805020 Rev. C 9/14/07 Page 12
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Technical S
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pecification
Input:
Input:
Output:
Output:
Current:
Current:
P
Package:
ackage:
9-36 V
9-36 V
5.0 V
5.0 V
20 A
20 A
Quarter-brick
Quarter-brick
PART NUMBERING SYSTEM
The part numbering system for SynQor’s InQor DC/DC con-
verters follows the format shown in the example below.
The first 12 characters comprise the base part number and the
last 3 characters indicate available options. The “-G” suffix
indicates 6/6 RoHS compliance.
Application Notes
A variety of application notes and technical white papers can
be downloaded in pdf format from our website.
PATENTS (additional patent applications may be filed)
SynQor holds the following patents, one or more of which
might apply to this product:
5,999,417 6,222,742 6,545,890 6,577,109
6,594,159 6,731,520 6,894,468 6,896,526
6,927,987 7,050,309 7,072,190 7,085,146
ORDERING INFORMATION
The tables below show the valid model numbers and ordering
options for converters in this product family. When ordering
SynQor converters, please ensure that you use the complete
15 character part number consisting of the 12 character base
part number and the additional 3 characters for options.
A “-G” suffix indicates the product is 6/6 RoHS compliant.
The following option choices must be included in place of the
x y z spaces in the model numbers listed above.
Output Max Output
Voltage Current
IQ18018QTw40xyz 9 - 36 V 1.8 V 40 A
IQ18033QTw30xyz 9 - 36 V 3.3 V 30 A
IQ18050QTw20xyz 9 - 36 V 5 V 20 A
IQ18070QTw14xyz 9 - 36 V 7 V 14 A
IQ18120QTw08xyz 9 - 36 V 12 V 8 A
IQ18150QTw07xyz 9 - 36 V 15 V 7 A
IQ18240QTw04xyz 9 - 36 V 24 V 4 A
IQ18300QTw03xyz 9 - 36 V 30 V 3 A
IQ18480QTw02xyz 9 - 36 V 48 V 2 A
Model Number
Input Voltage
Thermal Enable Pin Feature
Design Logic Length Set
A - Open Frame
B - Baseplated
C - Encased
N - Negati v e R - 0.180" S - Standard
Options Description: w x y z
Warranty
SynQor offers a three (3) year limited warranty. Complete warranty
information is listed on our website or is available upon request from
SynQor.
Information furnished by SynQor is believed to be accurate and reliable.
However, no responsibility is assumed by SynQor for its use, nor for any
infringements of patents or other rights of third parties which may result
from its use. No license is granted by implication or otherwise under any
patent or patent rights of SynQor.
Contact SynQor for further information:
Phone: 978-849-0600
Toll Free: 888-567-9596
Fax: 978-849-0602
E-mail: power@synqor.com
Web: www.synqor.com
Address: 155 Swanson Road
Boxborough, MA 01719
USA
IQ 18 050 Q T A 20 N R S -G
Product Family
Package Size
Performance Level
Thermal Design (see Ordering Info)
Output Current
6/6 RoHS
Options (see
Ordering Information)
Input Voltage
Output Voltage