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LTC4364 Burning out MOSFET

Thread Summary

The user designed an Ideal Diode Board using the LTC4364 with a 36-54.6V input and 30A max current. During testing, the NVMFS6H800NLWFT1G MOSFET burned out when a 10-ohm, 1000W resistor was connected to the output, drawing 5A at 54V. The final answer indicates that the MOSFET's Safe Operating Area (SOA) must be sufficient to handle the extra load current during startup. The user should verify the MOSFET's SOA for the startup conditions.
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Hi,

I’ve designed an Ideal diode Board using LTC4364.

Input voltage: 36~54.6V

Max current: 30A

I’ve tested the board and faced a problem.

Test setup:

A 10-ohm (1000 W) resistor is connected to the output connector(P2) and the Input voltage is ~54V.  So the load current will be around 5A

Main Mosfet: NVMFS6H800NLWFT1G

Problem: When I power on the board using the P1 connector, Q1 MOSFET burns out. (Mosfet's Drain to Source, will beep when the board is off using a multimeter). Without the load, everything is fine and the circuit works.

It should be mentioned that the selected Mosfets can handle current when Tc 100°C.

Also, some Dc-Dc converters are connected to the output side.

attached Schematic: drive.google.com/.../view