Advance Data Sheet: Maxeta
TM
iFA Series
©2005 TDK Innoveta Inc.
iFA Advance Datasheet 6/6/2005
10/18
Thermal Management:
An important part of the overall system
design process is thermal management;
thermal design must be considered at all
levels to ensure good reliability and lifetime
of the final system. Superior thermal design
and the ability to operate in severe
application environments are key elements
of a robust, reliable power module.
A finite amount of heat must be dissipated
from the power module to the surrounding
environment. This heat is transferred by the
three modes of heat transfer: convection,
conduction and radiation. While all three
modes of heat transfer are present in every
application, convection is the dominant
mode of heat transfer in most applications.
However, to ensure adequate cooling and
proper operation, all three modes should be
considered in a final system configuration.
The open frame design of the power module
provides an air path to individual
components. This air path improves
convection cooling to the surrounding
environment, which reduces areas of heat
concentration and resulting hot spots.
Test Setup: The thermal performance data
of the power module is based upon
measurements obtained from a wind tunnel
test with the setup shown in the wind tunnel
figure. This thermal test setup replicates the
typical thermal environments encountered in
most modern electronic systems with
distributed power architectures. The
electronic equipment in networking, telecom,
wireless, and advanced computer systems
operates in similar environments and utilizes
vertically mounted printed circuit boards
(PCBs) or circuit cards in cabinet racks.
The power module is mounted on a 0.062
inch thick, 6 layer, 2oz/layer PCB and is
vertically oriented within the wind tunnel.
Power is routed on the internal layers of the
PCB. The outer copper layers are thermally
decoupled from the converter to better
simulate the customer’s application. This
also results in a more conservative derating.
The cross section of the airflow passage is
rectangular with the space between the top
of the module or heatsink (where applicable)
and a parallel facing PCB is kept at a
constant (0.5 in). The power module’s
orientation with respect to the airflow
direction can have a significant impact on
the unit’s thermal performance.
Thermal De-rating
:
For proper application
of the power module in a given thermal
environment, output current de rating curves
are provided as a design guideline in the
Thermal Performance section for the power
module of interest. The module temperature
should be measured in the final system
configuration to ensure proper thermal
management of the power module. For
thermal performance verification, the module
temperature should be measured at the
location indicated in the thermal
measurement location figure on the Thermal
Air Velocity and Ambient
Temperature
Measurement Location
I
R
F
L
O
W
(0.50)
Centerline
Air Passage
Centerline
Wind Tunnel Test Setup Figure
Dimensions are in millimeters and (inches).
