GS61004B-EVBCD
GaN E-HEMT Full Bridge Evaluation Board
User’s Guide
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GS61004B-EVBCD Rev 200106
© 2020 GaN Systems Inc.
www.gansystems.com 23
Please refer to the Evaluation Board/Kit Important Notice on page 27
Thermal Considerations
The evaluation board includes four GS61004B transistors. Although the electrical performance surpasses
that for traditional silicon devices, their relatively smaller size does magnify the thermal management
requirements. The evaluation board is intended for bench evaluation with low ambient temperature and
convection cooling.
The addition of heat-sinking and forced air cooling can significantly increase the current rating of these
devices, but care must be taken to not exceed the absolute maximum die temperature of +125 °C.
The thermal performance of the GS61004B-EVBCD evaluation board is shown in
Figure 17
•
GS61004B-EVBCD EVB Thermal Plot Showing Maximum of 57
C with PWM 1.26
S
Pulse Width at 200 kHz, with 30V @1 A on HV PSU into 8 Ohm Resistive Load
With a 5:1 duty cycle corresponding to a near-maximum pulse width modulation index into a
suitable load, the hottest components are the resistors in the Zobel/Snubber Networks (if/when
fitted) and the inductors. However, in the absence of a periodic PWM input, the steady DC
quiescent state will draw a significantly higher standing current through the Gan E-HEMTs
consequently, care and heatsinking considerations will be required to accommodate the
resulting increased temperatures.
Note
: The switch node snubber networks were fitted at the time the thermal images were taken: that
is, R39 and C27, R27 and C19, whose resistors will become hot if fitted, as seen in these images.
Leaving these parts unfitted should improve efficiency slightly
