Timeline for How can I protect my MOSFET?
Current License: CC BY-SA 3.0
5 events
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| May 10, 2016 at 22:08 | comment | added | feetwet | So I want a Zener or TVS to shunt current when Vgs exceeds ~15V. I.e., "clamping" voltage should be under 15V? And, presumably, all other voltage specs for such a diode will be under 15V so any such will do, and in either orientation? Even though this circuit could present a voltage difference in the hundreds of volts? Or is there some other specification I need to watch? | |
| May 10, 2016 at 18:43 | comment | added | feetwet | I have only observed that the malfunctioning MOSTs have a G-D short. I.e., I take it as evidence that the MOST is blown. But I don't know why or how it happened. I just added clarification of the circuit's purpose in question comment. | |
| May 10, 2016 at 18:32 | comment | added | user68591 | If you get a G-D short it will kill the MOST and the Zener diodes with it. Maybe when connecting the transistor the gate caught some static or got charge through capacitive coupling and the voltage blew the gate oxide. Hard to tell what are you trying to do with this circuit, but do try the protection diodes first. They may point you to the source of the problem | |
| May 10, 2016 at 18:15 | comment | added | feetwet | So if the MOST failed with a short between gate and drain then it must have been caused by excessive voltage difference between gate and source? | |
| May 10, 2016 at 17:58 | history | answered | user68591 | CC BY-SA 3.0 |