Data Sheet
March 27, 2008
QBK025A0B Series DC-DC Converter Power Modules:
36- 55Vdc Input, 12Vdc Output and 25A Output Current
* UL is a registered trademark of Underwriters Laboratories, Inc.
† CSA is a registered trademark of Canadian Standards Association.
‡ VDE is a trademark of Verband Deutscher Elektrotechniker e.V.
** ISO is a registered trademark of the International Organization of Standards
Document No: DS03-096 ver. 1.46
PDF name: qbus_qbk025a0b_ds.pdf
Applications
Distributed power architectures
Servers and storage applications
Optical and Access Network Equipment
Enterprise Networks
Options
Negative logic, Remote On/Off
Active load sharing (Parallel Operation)
Baseplate option (-H)
Auto restart after fault shutdown
Case ground pin
Features
Compliant to RoHS EU Directive 2002/95/EC (-Z
versions)
Compliant to RoHS EU Directive 2002/95/EC with
lead solder exemption (non-Z versions)
Delivers up to 25A Output current
High efficiency – 94% at 12V full load
Industry standard Quarter brick footprint
57.9mm x 36.8mm x 10.6mm
(2.28in x 1.45in x 0.42in)
Low output ripple and noise
Cost efficient open frame design
Intermediate input voltage range
Output overcurrent/voltage protection
Over-temperature protection
Single optimal regulated output
Wide operating temperature range (-400C to 850C)
Positive logic, Remote On/Off
Complies with and is licensed for Basic Insulation
rating per EN60950-1
CE mark meets 73/23/EEC and 93/68/EEC
directives§
UL* 60950-1Recognized, CSA† C22.2 No. 60950-1-
03 Certified, and VDE‡ 0805:2001-12 (EN60950-1)
Licensed
ISO** 9001 and ISO 14001 certified manufacturing
facilities
Description
The QBK025A0B series of DC-DC converters are an expansion of a new generation of DC/DC power modules
designed to support 12Vdc intermediate bus applications where multiple low voltages are subsequently generated
using discrete/modular point of load (POL) converters. The QBK025A0B series provide up to 25A output current in
an industry standard quarter brick, which makes it an ideal choice for small space, high current and 12V
intermediate bus voltage applications. The converter incorporates synchronous rectification technology and
innovative packaging techniques to achieve efficiency reaching 94% at 12V full load. This leads to lower power
dissipations such that for many applications a heat sink is not required. The output is fully isolated from the input,
allowing versatile polarity configurations and grounding connections. Built-in filtering for both input and output
minimizes the need for external filtering.
RoHS Compliant
Data Sheet
March 27, 2008
QBK025A0B DC-DC Power Modules:
36-55Vdc Input; 12Vdc Output Voltage; 25A Output Current
LINEAGE POWER 2
Absolute Maximum Ratings
Stresses in excess of the absolute maximum ratings can cause permanent damage to the device. These are absolute
stress ratings only, functional operation of the device is not implied at these or any other conditions in excess of those
given in the operations sections of the data sheet. Exposure to absolute maximum ratings for extended periods can
adversely affect the device reliability.
Parameter Device Symbol Min Max Unit
Input Voltage*
Continuous VIN -0.3 55 Vdc
Non- operating continuous VIN -0.3 75 Vdc
Operating Ambient Temperature All TA -40 85 °C
(See Thermal Considerations section)
Storage Temperature All Tstg -55 125 °C
I/O Isolation Voltage (100% factory Hi-Pot tested) All ⎯ ⎯ 1500 Vdc
* Input over voltage protection will shutdown the output voltage when the input voltage exceeds threshold level.
Electrical Specifications
Unless otherwise indicated, specifications apply over all operating input voltage, resistive load, and temperature
conditions.
Parameter Device Symbol Min Typ Max Unit
Operating Input Voltage VIN 36 48 55 Vdc
Maximum Input Current IIN,max - - 9.5 Adc
(VIN=0V to 55V, IO=IO, max)
Inrush Transient All I2t - - 1 A2s
Input Reflected Ripple Current, peak-to-peak
(5Hz to 20MHz, 12μH source impedance; VIN=
48V, IO= IOmax ; see Figure 9)
All - 24 - mAp-p
Input Ripple Rejection (120Hz) All - -50 - dB
CAUTION: This power module is not internally fused. An input line fuse must always be used.
This power module can be used in a wide variety of applications, ranging from simple standalone operation to an
integrated part of a sophisticated power architecture. To preserve maximum flexibility, internal fusing is not included,
however, to achieve maximum safety and system protection, always use an input line fuse. The safety agencies require a
fast-acting fuse with a maximum rating of 15A (see Safety Considerations section). Based on the information provided in
this data sheet on inrush energy and maximum dc input current, the same type of fuse with a lower rating can be used.
Refer to the fuse manufacturer’s data sheet for further information.
Data Sheet
March 27, 2008
QBK025A0B DC-DC Power Modules:
36-55Vdc Input; 12Vdc Output Voltage; 25A Output Current
LINEAGE POWER 3
Electrical Specifications (continued)
Parameter Device Symbol Min Typ Max Unit
Output Voltage Set-point 12 VO, set 12 Vdc
(VIN=VIN,nom, IO=15A, Ta =25°C)
Output Voltage VO 11.4 ⎯ 12.6 Vdc
(Over all operating input voltage, resistive
load, and temperature conditions until end of
life)
Output Regulation
Line (VIN = VIN, min to VIN, max) All
⎯ 0.2 ⎯ %Vo
Load (IO = IO, min to IO, max) All
⎯ 3 ⎯ %Vo
Temperature (Tref =TA, min to TA, max) All
⎯ 150 ⎯ mV
Output Ripple and Noise on nominal output
(VIN =VIN, nom and IO = IO, min to IO, max,
RMS (5Hz to 20MHz bandwidth) All ⎯ 70 ⎯ mVrms
Peak-to-Peak (5Hz to 20MHz bandwidth) All ⎯ 200 ⎯ mVpk-pk
External Capacitance All CO, max ⎯ ⎯ 10,000 μF
Output Current 12V Io 0 25 Adc
Output Current Limit Inception (Hiccup Mode)
(Vo = 90% Vo, set ) 12V IO, lim ⎯ 28.5 ⎯ Adc
Efficiency 12V η __
94
⎯
%
VIN= 48V, T
A
=25°C, IO= IO
,
max
Switching Frequency fsw ⎯ 300 ⎯ KHz
Dynamic Load Response
(dIO/dt=0.1A/μs; VIN=VIN, nom; TA=25°C)
Load change from IO = 50% to 75% of IO, max
Peak Deviation 12V Vpk ⎯ 2 ⎯ % VO
Settling Time (VO<10% peak deviation) ts ⎯ 200 ⎯ μs
Load change from IO = 50% to 25% of IO, max,
Peak Deviation 12V Vpk ⎯ 2 ⎯ % VO
Settling Time (VO<10% peak deviation) ts ⎯ 200 ⎯ μs
Isolation Specifications
Parameter Symbol Min Typ Max Unit
Isolation Capacitance Ciso ⎯ 2000 ⎯ pF
Isolation Resistance Riso 10 ⎯ ⎯ MΩ
General Specifications
Parameter Min Typ Max Unit
Calculated MTBF (IO=80% of IO, max, TA=25°C,
airflow=1m/s(200LFM)) 2,600,000 Hours
Weight ⎯ 44 (1.55) g (oz.)
Data Sheet
March 27, 2008
QBK025A0B DC-DC Power Modules:
36-55Vdc Input; 12Vdc Output Voltage; 25A Output Current
LINEAGE POWER 4
Feature Specifications
Unless otherwise indicated, specifications apply over all operating input voltage, resistive load, and temperature
conditions. See Feature Descriptions for additional information.
Parameter Device Symbol Min Typ Max Unit
Remote On/Off Signal Interface
(VIN=VIN, min to VIN, max , Signal referenced to VIN-
terminal)
Negative Logic: Device code suffix “1”
Logic Low = module On, Logic High = module Off
Positive Logic: No device code suffix required
Logic Low = module Off, Logic High = module On
On/Off Thresholds:
Remote On/Off Current – Logic Low All Ion/off 5 10 15 μA
Logic Low Voltage All Von/off 0.0 ⎯ 0.8 V
Logic High Voltage – (Typ = Open Collector) All Von/off 2.0 ⎯ 5.0 V
Logic High maximum allowable leakage current
(Von/off = 2.0V) All Ion/off ⎯ ⎯ 6.0 μA
Maximum voltage allowed on On/Off pin All Von/off ⎯ ⎯ 14.0 V
Turn-On Delay and Rise Times
(IO= IO, max , VIN=VIN, nom, TA = 25 oC)
Case 1: Time until VO = 10% of VO,set from
application of Vin with Remote On/Off set to On 12 Tdelay
Enable with Vin ― 15 ― msec
Case 2: Time until VO = 10% of VO,set from
operation of Remote On/Off from Off to On with Vin
already applied for at least one second.
Tdelay
Enable with on/off ― 1.5 ― msec
Output Voltage Rise time (time for Vo to rise from
10% of Vo, set to 90% of Vo, set)
Trise ― 1 ― msec
Over Temperature Protection All Tref ⎯ 125 ⎯ °C
(See Thermal Considerations section)
Input Under Voltage Lockout VUVLO
Turn-on Threshold ⎯ 35 36 V
Turn-off Threshold 32 34
⎯ V
Over Voltage Protection 12V 13 ⎯ 15 V
Data Sheet
March 27, 2008
QBK025A0B DC-DC Power Modules:
36-55Vdc Input; 12Vdc Output Voltage; 25A Output Current
LINEAGE POWER 5
Characteristic Curves
The following figures provide typical characteristics for QBK025A0B (12V, 25A) at 25ºC. The figures are identical for
either positive or negative Remote On/Off logic.
0
1
2
3
4
5
6
7
8
9
10
30 35 40 45 50 55
Io=25A
Io=12.5A
Io=0 A
INPUT CURRENT, Ii (A)
INPUT VOLTAGE, VO (V)
On/Off VOLTAGE OUTPUT VOLTAGE
VON/OFF(V) (2V/div) VO (V) (5V/div)
TIME, t (500 μs/div)
Figure 1. Typical Input Characteristic at Room
Temperature.
Figure 4. Typical Start-Up Using Remote On/Off,
negative logic version shown.
70
75
80
85
90
95
100
0 5 10 15 20 25
Vin=36V
Vin=48V
Vin=55V
EFFCIENCY, η (%)
OUTPUT CURRENT, IO (A)
OUTPUT CURRENT, OUTPUT VOLTAGE
IO (A) (5A/div) VO (V) (500mV/div)
TIME, t (200 μs/div)
Figure 2. Typical Converter Efficiency Vs. Output
current at Room Temperature.
Figure 5. Typical Transient Response to Step
change in Load from 25% to 50% to 25% of Full
Load at Room Temperature and 48 Vdc Input.
OUTPUT VOLTAGE,
VO (V) (100mV/div)
TIME, t (1μs/div)
OUTPUT CURRENT, OUTPUT VOLTAGE
IO (A) (5A/div) VO (V) (500mV/div)
TIME, t (200 μs/div)
Figure 3. Typical Output Ripple and Noise at Room
Temperature and Io = Io,max .
Figure 6. Typical Transient Response to Step
Change in Load from 50% to 75% to 50% of Full
Load at Room Temperature and 48 Vdc Input.
55 Vin
48 Vin
36 Vin
Data Sheet
March 27, 2008
QBK025A0B DC-DC Power Modules:
36-55Vdc Input; 12Vdc Output Voltage; 25A Output Current
LINEAGE POWER 6
Characteristic Curves (continued)
11.7
11.8
11.9
12
12.1
12.2
12.3
36 41 46 51 56
Io=25A
Io=12.5A
Io=0 A
OUTPUT VOLTAGE, VO (V)
INPUT VOLTAGE, Vin (V)
Figure 7. Typical Output voltage regulation vs. Input
voltage at Room Temperature.
OUTPUT VOLTAGE, VO (V)
OUTPUT CURRENT, IO (A)
Figure 8. Typical Output voltage regulation Vs. Output
current at Room Temperature.
11.7
11.8
11.9
12
12.1
12.2
0 5 10 15 20 25
Vin=36V
Vin=48V
Vin=55V
Data Sheet
March 27, 2008
QBK025A0B DC-DC Power Modules:
36-55Vdc Input; 12Vdc Output Voltage; 25A Output Current
LINEAGE POWER 7
Test Configurations
Note: Measure input reflected-ripple current with a simulated
source inductance (LTEST) of 12 µH. Capacitor CS offsets
possible battery impedance. Measure current as shown
above.
Figure 9. Input Reflected Ripple Current Test
Setup.
Note: Use a 1.0 µF ceramic capacitor and a 10 µF aluminum
or tantalum capacitor. Scope measurement should be made
using a BNC socket. Position the load between 51 mm and
76 mm (2 in. and 3 in.) from the module.
Figure 10. Output Ripple and Noise Test Setup.
LOAD
CONTACT AND
SUPPLY
I
I
CONTACT
V
I
(+)
V
I
(–)
V
O1
DISTRIBUTION LOSSES
RESISTANCE
I
O
V
O2
Note: All measurements are taken at the module terminals.
When socketing, place Kelvin connections at module
terminals to avoid measurement errors due to socket contact
resistance.
Figure 11. Output Voltage and Efficiency Test
Setup.
Design Considerations
Input Source Impedance
The power module should be connected to a low
ac-impedance source. A highly inductive source
impedance can affect the stability of the power
module. For the test configuration in Figure 9, a 100μF
electrolytic capacitor (ESR<0.7Ω at 100kHz), mounted
close to the power module helps ensure the stability of
the unit. Consult the factory for further application
guidelines.
Safety Considerations
For safety-agency approval of the system in which the
power module is used, the power module must be
installed in compliance with the spacing and
separation requirements of the end-use safety agency
standard, i.e., UL 1950, CSA C22.2 No. 60950-00,
and VDE 0805:2001-12 (IEC60950 3rd Ed).
If the input source is non-SELV, for the module’s
output to be considered as meeting the requirements
for safety extra-low voltage (SELV), all of the following
must be true:
The input source is to be provided with reinforced
insulation from any other hazardous voltages,
including the ac mains.
One VIN pin and one VOUT pin are to be grounded,
or both the input and output pins are to be kept
floating.
The input pins of the module are not operator
accessible.
Another SELV reliability test is conducted on the
whole system (combination of supply source and
subject module), as required by the safety
agencies, to verify that under a single fault,
hazardous voltages do not appear at the
module’s output.
Note: Do not ground either of the input pins of the
module without grounding one of the output
pins. This may allow a non-SELV voltage to
appear between the output pins and ground.
The power module has extra-low voltage (ELV)
outputs when all inputs are ELV.
The input to these units is to be provided with a
maximum 15 A fast-acting (or time-delay) fuse in the
unearthed lead.
Data Sheet
March 27, 2008
QBK025A0B DC-DC Power Modules:
36-55Vdc Input; 12Vdc Output Voltage; 25A Output Current
LINEAGE POWER 8
Feature Description
Remote On/Off
Two remote on/off options are available. Positive logic
remote on/off turns the module on during a logic-high
voltage on the ON/OFF pin, and off during a logic low.
Negative logic remote on/off turns the module off
during a logic high and on during a logic low. Negative
logic, device code suffix "1," is the factory-preferred
configuration. The on/off circuit is powered from an
internal bias supply. To turn the power module on and
off, the user must supply a switch to control the
voltage between the on/off terminal and the Vi (-)
terminal (Von/off). The switch can be an open
collector or equivalent (see Figure 12). A logic low is
Von/off = 0.0V to 0.8V. The typical Ion/off during a
logic low is 10 µA. The switch should maintain a logic-
low voltage while sinking 10µA. During a logic high,
the maximum Von/off generated by the power module
is 5.0V. The maximum allowable leakage current of
the switch at Von/off = 2.0V is 6.0µA. If using an
external voltage source, the maximum voltage V on/off
on the pin is 14.0V with respect to the Vi (-) terminal. If
not using the remote on/off feature, perform one of the
following to turn the unit on:
For negative logic, short ON/OFF pin to VI(-).
For positive logic: leave ON/OFF pin open.
V
O
(+)
V
O
(–)
V
I
(–)
+
–
I
on/off
ON/OFF
V
I
(+)
LOA
D
V
on/off
Figure 10. Circuit configuration for using Remote
On/Off Implementation.
Over Current Protection
To provide protection in a fault output overload
condition, the module is equipped with internal
current-limiting circuitry and can endure current
limiting for a few mili-seconds. If the over current
condition persists beyond a few milliseconds, the
module will shut down and remain latched off. The
over current latch is reset by either cycling the input
power or by toggling the on/off pin for one second. If
the output overload condition still exists when the
module restarts, it will shut down again. This operation
will continue indefinitely until the over current condition
is corrected.
An auto-restart option is also available. An auto-restart
feature continually attempts to restore the operation
until fault condition is cleared.
Input Under/Over Voltage Lockout
At input voltages above or below the input under/over
voltage lockout limits, module operation is disabled.
The module will begin to operate when the input
voltage level changes to within the under and
overvoltage lockout limits.
Over Temperature Protection
These modules feature an over temperature
protection circuit to safeguard against thermal
damage. The circuit shuts down and latches off the
module when the maximum device reference
temperature is exceeded. The module can be
restarted by cycling the dc input power for at least one
second or by toggling the remote on/off signal for at
least one second.
Output Over Voltage Clamp
The output overvoltage clamp consists of a control
circuit, independent of the primary regulation loop, that
monitors the voltage on the output terminals and
clamps the voltage when it exceeds the overvoltage
set point. The control loop of the clamp has a higher
voltage set point than the primary loop. This provides
a redundant voltage control that reduces the risk of
output overvoltage.
Data Sheet
March 27, 2008
QBK025A0B DC-DC Power Modules:
36-55Vdc Input; 12Vdc Output Voltage; 25A Output Current
LINEAGE POWER 9
Feature Description (continued)
Forced Load Sharing (Parallel Operation with
– P option)
For additional power requirements, the power module
can be configured for parallel operation with active
load current sharing. Good layout techniques should
be observed for noise immunity when using multiple
modules in parallel. To implement active load sharing,
the following recommendations must be followed:
• The parallel pins of all units in parallel must be
connected together. The path of these
connections should be as direct as possible, but
should not pass beneath the perimeter of the
module body, except immediately adjacent to the
parallel pin location.
• Parallel modules must use the same 48V source.
The VIN (-) input pin is the return path for the
active current share signal of the parallel pin.
Separate 48V sources will prevent the active
current share return signal from being connected
to other modules.
• The VIN (-) input connection should never be
disconnected from any of the parallel modules,
while another of the parallel modules is operating,
unless the VIN (+) pin, or the parallel pin is also
disconnected. The VIN (-) input provides the
internal logic ground and for the module’s primary
circuits, including the active current share circuit;
and there are sneak paths through the module’s
internal control ICs, when the VIN (-) pin is
disconnected (allowing the internal logic circuit to
float), while the parallel pin and VIN (+) pin are
connected to other operating modules. These
sneak paths do not cause permanent damage,
but do create false conditions that can affect the
module’s internal logic configuration.
• The on/off pins of all modules should also be tied
together to the same external control circuitry, so
that the modules are turned on and off at the
same time, unless all parallel modules’ on/off pins
are tied to the input pins for automatic start upon
application of input voltage.
• When modules in parallel applications contain the
auto-restart (4) option, it is required that the total
maximum load current value be less than 90% of
[n-1] times the individual module output current
rating, where n is the number of modules in
parallel. For example, if the application is using
three modules rated at 25A, then the maximum
total load shall be less than 0.9 x (3-1) x 25A =
0.9 x 2 x 25A = 45A. This insures that a single
module can shutdown without causing the total
load to exceed the capability of the remaining
operating module(s). The shutdown module can
then automatically restart, and assume its share
of the total load.
• In all parallel applications (including applications
meeting the [n-1] sizing criteria discussed earlier),
if it is expected that a protective shutdown event
could cause more than one parallel module to
shutdown (for example, over temperature due to
a common fan failure, or gross over current
affecting two or more modules simultaneously),
then the use of the auto-restart (4) option is not
recommended. The auto-restart interval of these
modules is not synchronized to other modules,
nor is it precise. There will not be a successful
restart following multiple module shutdowns,
because the individual module’s restart timings
will be different. There will not be sufficient
module capacity to prevent the first module which
restarts from experiencing an over current, and
then again shutting down before the slowest
module has restarted. Meanwhile, the slowest
module will then restart, and then shutdown
during the interval the fastest module is waiting
for its next restart. And so on and so on. In these
cases, only latching shutdown modules should be
used; and either toggling the Vin source or the
on/off pin to simultaneously restart the modules,
following a shutdown, is advised.
When not using the parallel feature, leave the share
pin open.
Data Sheet
March 27, 2008
QBK025A0B DC-DC Power Modules:
36-55Vdc Input; 12Vdc Output Voltage; 25A Output Current
LINEAGE POWER 10
Thermal Considerations
The power modules operate in a variety of thermal
environments and sufficient cooling should be
provided to help ensure reliable operation.
Thermal considerations include ambient temperature,
airflow, module power dissipation, and the need for
increased reliability. A reduction in the operating
temperature of the module will result in an increase in
reliability. The thermal data presented here is based
on physical measurements taken in a wind tunnel.
Heat-dissipating components are mounted on the top
side of the module. Heat is removed by conduction,
convection and radiation to the surrounding
environment. Proper cooling can be verified by
measuring the thermal reference temperature (TH).
Peak temperature (TH) occurs at the position indicated
in Figure 13. For reliable operation this temperature
should not exceed the listed temperature threshold.
Figure 13. Location of the thermal reference
temperature TH.
The output power of the module should not exceed
the rated power for the module as listed in the
Ordering Information table.
Although the maximum TH temperature of the power
modules is 110 °C - 115 °C, you can limit this
temperature to a lower value for extremely high
reliability.
Please refer to the Application Note “Thermal
Characterization Process For Open-Frame Board-
Mounted Power Modules” for a detailed discussion of
thermal aspects including maximum device
temperatures.
Heat Transfer via Convection
Increased airflow over the module enhances the heat
transfer via convection. The thermal derating figures
(14-16) show the maximum output current that can be
delivered by each module in the respective orientation
without exceeding the maximum TH temperature
versus local ambient temperature (TA) for air flows of 1
m/s (200 ft./min) and 2m/s (400 ft./min).
Note that the natural convection condition was
measured at 0.05 m/s to 0.1 m/s (10ft./min. to 20
ft./min.); however, systems in which these power
modules may be used typically generate natural
convection airflow rates of 0.3 m/s (60 ft./min.) due to
other heat dissipating components in the system. The
use of Figures 14 - 15 are shown in the following
example:
Example
What is the minimum airflow necessary for a
QBK025A0B operating at VI = 48 V, an output current
of 12A, and a maximum ambient temperature of 70 °C
in transverse orientation.
Solution:
Given: VI = 48V, Io = 12A, TA = 70 °C
Determine required airflow (V) (Use Figure 14):
V = T1 m/sec. ( 200 ft./min.) or greater.
0
5
10
15
20
25
30
0 20406080100
Natural Convection
1m/s (200LFM)
2m/s (400LFM)
3m/s
(
600LFM
)
OUTPUT CURRENT, IO (A)
LOCAL AMBIENT TEMPERATURE, TA (°C)
Figure 14. Output Current Derating for the
QBK025A0B in the Transverse Orientation with no
baseplate; Airflow Direction from Vin(+) to Vin(-); Vin
= 48V.
Data Sheet
March 27, 2008
QBK025A0B DC-DC Power Modules:
36-55Vdc Input; 12Vdc Output Voltage; 25A Output Current
LINEAGE POWER 11
Thermal Derating Curves
0
5
10
15
20
25
30
0 20406080100
Natural Convection
1m/s
(
200LFM
)
2m/s
(
400LFM
)
3m/s
(
600LFM
)
OUTPUT CURRENT, IO (A)
LOCAL AMBIENT TEMPERATURE, TA (°C)
Figure 15. Output Current Derating for the
QBK025A0B (Vo = 12V) in the Transverse Orientation
with baseplate.
0
5
10
15
20
25
30
0 20406080100
1m/s
(
200LFM
)
2m/s
(
400LFM
)
3m/s
(
600LFM
)
OUTPUT CURRENT, IO (A)
LOCAL AMBIENT TEMPERATURE, TA (°C)
Figure 16. Output Current Derating for the
QBK025A0B (Vo = 12V) in the Transverse Orientation
with baseplate and 0.25-inch high heatsink.
0
5
10
15
20
25
30
0 20406080100
1m/s
(
200LFM
)
2m/s
(
400LFM
)
3m/s
(
600LFM
)
OUTPUT CURRENT, IO (A)
LOCAL AMBIENT TEMPERATURE, TA (°C)
Figure 17. Output Current Derating for the
QBK025A0B (Vo = 12V) in the Transverse Orientation
with baseplate and 0.5-inch high heatsink.
Data Sheet
March 27, 2008
QBK025A0B DC-DC Power Modules:
36-55Vdc Input; 12Vdc Output Voltage; 25A Output Current
LINEAGE POWER 12
Layout Considerations
The QBK025 power module series are low profile in
order to be used in fine pitch system card architectures.
As such, component clearance between the bottom of
the power module and the mounting board is limited.
Avoid placing copper areas on the outer layer directly
underneath the power module. Also avoid placing via
interconnects underneath the power module.
For additional layout guide-lines, refer to FLTR100V10
data sheet.
Through-Hole Lead-Free Soldering
Information
The RoHS-compliant through-hole products use the
SAC (Sn/Ag/Cu) Pb-free solder and RoHS-compliant
components. They are designed to be processed
through single or dual wave soldering machines. The
pins have an RoHS-compliant finish that is compatible
with both Pb and Pb-free wave soldering processes. A
maximum preheat rate of 3°C/s is suggested. The
wave preheat process should be such that the
temperature of the power module board is kept below
210°C. For Pb solder, the recommended pot
temperature is 260°C, while the Pb-free solder pot is
270°C max. Not all RoHS-compliant through-hole
products can be processed with paste-through-hole Pb
or Pb-free reflow process. If additional information is
needed, please consult with your Lineage Power
representative for more details.
Post Solder Cleaning and Drying
Considerations
Post solder cleaning is usually the final circuit-board
assembly process prior to electrical board testing. The
result of inadequate cleaning and drying can affect both
the reliability of a power module and the testability of the
finished circuit-board assembly. For guidance on
appropriate soldering, cleaning and drying procedures,
refer to Lineage Power Board Mounted Power Modules:
Soldering and Cleaning Application Note
(AP01-056EPS).
Data Sheet
March 27, 2008
QBK025A0B DC-DC Power Modules:
36-55Vdc Input; 12Vdc Output Voltage; 25A Output Current
LINEAGE POWER 13
Mechanical Outline
Dimensions are in millimeters and (inches).
Tolerances: x.x mm ± 0.5 mm (x.xx in. ± 0.02 in.) [Unless otherwise indicated]
x.xx mm ± 0.25 mm (x.xxx in ± 0.010 in.)
TOP
VIEW
SIDE
VIEW
BOTTOM
VIEW
36.8
(1.45)
57.9
(2.28)
4.6
(.18) MIN
1.57 (.062) DIA SOLDER PLATED
PIN SHOULDER, 5 PLCS
1.02 (.040) DIA SOLDER PLATED
PIN, 5 PLCS
0.25
(.010)MIN 2.36 (.093) DIA SOLDER-PLATED
PIN SHOULDER, 2 PLCS
1.57 (.062) DIA SOLDER-PLATED
PIN, 2 PLCS
3.6
(.14)
7.62
(.300) 3.81
(.150)
11.43
(.450)
15.24
(.600)
VI(-)
VI(+)
ON/OFF
50.8
(2.000)
10.8
(.43)
15.24
(.600)
VO(-)
VO(+)
CASE
PARALLEL
10.5
(.41)
*Top side label includes Lineage Power name, product designation, and data code.
†Option Feature, Pin is not present unless one these options specified.
Data Sheet
March 27, 2008
QBK025A0B DC-DC Power Modules:
36-55Vdc Input; 12Vdc Output Voltage; 25A Output Current
LINEAGE POWER 14
Mechanical Outline for module with base plate.
Dimensions are in millimeters and [inches].
Tolerances: x.x mm ± 0.5 mm [x.xx in. ± 0.02 in.] (Unless otherwise indicated)
x.xx mm ± 0.25 mm [x.xxx in ± 0.010 in.]
TOP
VIEW
SIDE
VIEW
BOTTOM
VIEW
*Bottom side label includes Lineage Power name, product designation, and data code.
†Option Feature, Pin is not present unless one these options specified.
Data Sheet
March 27, 2008
QBK025A0B DC-DC Power Modules:
36-55Vdc Input; 12Vdc Output Voltage; 25A Output Current
LINEAGE POWER 15
Recommended Pad Layout
Dimensions are in millimeters and (inches).
Tolerances: x.x mm ± 0.5 mm (x.xx in. ± 0.02 in.) [Unless otherwise indicated]
x.xx mm ± 0.25 mm (x.xxx in ± 0.010 in.)
50.80
(2.000)
Vo (+)
Vo (-)
15.24
(.600)
V
I
(+)
V
I
(-)
†
†
ON/OFF
3.6
(.14)
10.8
(.43)
57.9
(2.28)
36.8
(1.45)
1.02 (.040) DIA PIN, 5 PLCS
1.57 (.062) DIA PIN, 2 PLCS
CASE
PARALLEL
†Option Feature, Pin is not present unless one these options specified.
Data Sheet
March 27, 2008
QBK025A0B DC-DC Power Modules:
36-55Vdc Input; 12Vdc Output Voltage; 25A Output Current
Document No: DS03-096 ver. 1.46
PDF name: qbus_qbk025a0b_ds.pdf
Ordering Information
Please contact your Lineage Power Sales Representative for pricing, availability and optional features.
Table 1. Device Code
Input Voltage Output
Voltage
Output
Current
Efficiency Connector
Type Product codes Comcode
48V (36-55Vdc) 12V 25A 94% Through hole QBK025A0B1 108988663
48V (36-55Vdc) 12V 25A 94% Through hole QBK025A0B1-H 108988671
48V (36-55Vdc) 12V 25A 94% Through hole QBK025A0B741-BH 108989471
48V (36-55Vdc) 12V 25A 94% Through hole QBK025A0B41-BH CC109125151
48V (36-55Vdc) 12V 25A 94% Through hole QBK025A0B41-PH 108992855
48V (36-55Vdc) 12V 25A 94% Through hole QBK025A0B71-BPH CC109104015
48V (36-55Vdc) 12V 25A 94% Through hole QBK025A0B741-BPH 108989348
48V (36-55Vdc) 12V 25A 94% Through hole QBK025A0B1Z CC109107884
48V (36-55Vdc) 12V 25A 94% Through hole QBK025A0B41-BHZ CC109129243
48V (36-55Vdc) 12V 25A 94% Through hole QBK025A0B1-PHZ CC109138541
48V (36-55Vdc) 12V 25A 94% Through hole QBK025A0B71-BHZ CC109139465
Table 2. Device Options
Option Suffix
Negative remote on/off logic 1
Auto-restart 4
Pin Length: 3.68 mm ± 0.25 mm (0.145 in. ± 0.010 in) 6
Case ground pin (offered with baseplate option only) 7
Base Plate option -H
Active load sharing (Parallel Operation) -P
Indicates RoHS Compliant part -Z
Note: Legacy device codes may contain a –B option suffix to indicate 100% factory Hi-Pot tested to the isolation voltage specified in
the Absolute Maximum Ratings table. The 100% Hi-Pot test is now applied to all device codes, with or without the –B option suffix.
Existing comcodes for devices with the –B suffix are still valid; however, no new comcodes for devices containing the –B suffix will be
created.
World Wide Headquarters
Lineage Power Corporation
3000 Skyline Drive, Mesquite, TX 75149, USA
+1-800-526-7819
(Outside U.S.A.: +1-972-284-2626)
www.lineagepower.com
e-mail: techsupport1@lineagepower.com
Asia-Pacific Headquarters
Tel: +65 6416 4283
Europe, Middle-East and Africa Headquarters
Tel: +49 89 6089 286
India Headquarters
Tel: +91 80 28411633
Lineage Power reserves the right to make changes to the product(s) or information contained herein without notice. No liability is assumed as a result of their use or
application. No rights under any patent accompany the sale of any such product(s) or information.
© 2008 Lineage Power Corporation, (Mesquite, Texas) All International Rights Reserved.
