Typical Over-Current Protection Performance With Wab300M12Bm3 - Broadcom ACPL-355JC Reference Manual

ACPL-355JC Reference Manual 62-mm SiC Module EB1200M62-355JC Evaluation Board
Figure 31: Turn-off switching energy loss at 600V DC bus. In the upper diagram, voltage waveforms are depicted with solid lines,
and current waveforms are depicted with dashed lines.

4.3 Typical Over-Current Protection Performance with WAB300M12BM3

The over-current protection function is demonstrated by short-circuiting the output of the power module WAB300M12BM3.
Figure 32 shows the measurement results. For safety reasons, gate driver over-current protection on this board is set to limit
the current at approximately 1400A within 2.5 µs, as described in Section 3.2.3, Protection Features. This corresponds to a
short circuit loop inductance of approximately 1.5 µH. It is recommended to use the board with a minimal short circuit limiting
inductance of approximately 1 µH. Since the SiC MOSFET turns on significantly faster than a typical IGBT, direct short circuit
(simultaneous turn-on of both the top and bottom switch) may result in extreme current values within a very short time, much
shorter than the SC time specified by the module manufacturers. Please note that some of the manufactures do not specify
the short circuit robustness at all, so if such a module is used, short circuit stress should be avoided. The soft turn-off function
of the ACPL-335JC provides excellent protection from over-voltage during the turn-off phase after the short circuit detection,
which can be observed on the voltage waveform in Figure 32.
Broadcom ACPL-355JC-62mmSiC-RM100
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