Hello!
I'm using a mosfet from SGS-THOMSON, the VND5N07 to switch a lamp with pwm. I drive it with a 4 Amps mosfet driver, the MCP14E3. A 22 Ohm resistor is placed between the driver and the mosfet.
This mosfet has the feature of being autoprotected, when the threshold temperature is reached, the gate is disconnected from the mosfet, and is connected to ground via a 100 Ohm resistor, so that the input voltage can be monitored for diagnostic purposes.
Now, if the device go in protection mode, the driver will sink to ground all the 14 volts with which it's supplied via an equivalent resistance of 122 Ohm, for a current of about 115 milliamps. This means I would need a 2 watt resistor, right?
So I thought to overcome this problem using a 1k resistor, instead of 22 Ohm, and to avoid switching speed losses, place a capacitor in parallel with the resistor.
Do you think this could be a reliable solution?
What value should I choose for the capacitor?
I'm using a mosfet from SGS-THOMSON, the VND5N07 to switch a lamp with pwm. I drive it with a 4 Amps mosfet driver, the MCP14E3. A 22 Ohm resistor is placed between the driver and the mosfet.
This mosfet has the feature of being autoprotected, when the threshold temperature is reached, the gate is disconnected from the mosfet, and is connected to ground via a 100 Ohm resistor, so that the input voltage can be monitored for diagnostic purposes.
Now, if the device go in protection mode, the driver will sink to ground all the 14 volts with which it's supplied via an equivalent resistance of 122 Ohm, for a current of about 115 milliamps. This means I would need a 2 watt resistor, right?
So I thought to overcome this problem using a 1k resistor, instead of 22 Ohm, and to avoid switching speed losses, place a capacitor in parallel with the resistor.
Do you think this could be a reliable solution?
What value should I choose for the capacitor?
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