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well the simplest way is 2 resistors and a zener, but that tends to be slow. What are you trying to do? You do not need 2 FETs for DC.
Dan
use your transistor to interrupt a 1mA current sink ( base to 5V, emitter to 5K, 5K to your collector)
current sink collector to 10K and 15V zener across PFET gate source
Sorry ... that is the job of the current source and I forgot tell you to put a 24V zener to your transistor base for the actual voltage senseI didnt get you ? a 15V zener will not handel 200V DC in case its the over voltage condition . I try to turn on the transistor when there is enough current at 25V Dc to produce a Vbe of .6V .
Sorry ... that is the job of the current source and I forgot tell you to put a 24V zener to your transistor base for the actual voltage sense
Gate drive would require gate power and is only needed for high speed circuits. This is simple and there was no indication that it needed great response time, just an overvoltage switch.ok...i think u should have a gate drive circuit to drive the gate of each mosfet. Gate drive can be opto-coupler and transistors joining together. Adding zener diode and resistor for overvoltage protection or adding clamping diode and resistor for faster switching turn on and off time.
you are not the OPer. It is the application requirement and not the part capability that determines if you need a driver or not.yup...this is for high speed and high voltage mosfets..
no, like this
Now I am confused. I was thinking you meant that the supply to the SMPS was going high and you needed to disconnect it.
Crowbars are pretty easy, the simplest being a zener firing an SCR to blow the fuse.
Dan
you are applying 200 to the output of a 12V switcher?
Original Posterwut is OPer?
Well that makes more sense. What is the current requirement? If it does not need much all you need is a series resistor.Not Me but its often happening as an accidental application at the remote sensor(25feet away) because of wiring mistake! when ever it happens. The sensor gets its supply from the mainboard. Now the Sensor is saved because of Crowbar but the supply blows off, any trick to save the supply.
-Adi