QW010/015/020 Series Brick Power Modules:
Data Sheet
36 - 75Vdc Input; 1.0Vdc to 5Vdc Output; 10A to 20A Output current
March 27, 2008
Thermal considerations
The baseplate option (-H) power modules are
constructed with baseplate on topside of the open frame
power module. The baseplate includes quarter brick
through-threaded, M3 x 0.5 mounting hole pattern, which
enable heat sinks or cold plates to attach to the module.
The mounting torque must not exceed 0.56 N-m (5 in.-
lb.) during heat sink assembly. This module operates in a
variety of thermal environments; however, sufficient
cooling should be provided to help ensure reliable
operation.
Tref
AirFlow
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 and coupled to the baseplate with
thermal gap material. Heat is removed by conduction,
convection and radiation to the surrounding environment.
The thermal reference point, Tref . used for the derating
Figure 1. Tref Temperature Measurement
Location
curves is shown in Figure 1. For reliable operation Tref
temperature should not exceed 118°C.
.
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 Tref
temperature of the power modules is 118°C, users can
limit this temperature to a lower value for extremely high
reliability.
Heat Transfer via Convection
Increased airflow over the module enhances the heat
transfer via convection. Following derating figures
shows the maximum output current that can be delivered
by each module in the respective orientation without
exceeding the maximum Tref temperature versus local
ambient temperature (TA) for natural convection through
1m/s (200 ft./min).
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.
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.
LINEAGE POWER
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