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Hi.
For a motor speed control, the output mosfet usually has its gate with a pull-down resistor to source to keep it off; and the PWM square wave source is fed into the gate with usually a small value resistor in series.
If the PWM signal source has a capacitor at its output, would that ensure the Mosfet would never stay on if the PWM source fails and stays 'high' ?
Is it a common practice to feed signal into a mosfet gate trough a capacitor ? Why ?
Say pin 5 with a series capacitor in this random example borrowed from the web:
----> https://www.circuitstoday.com/wp-content/uploads/2010/01/speed-control-for-PCB-drill.png
For a motor speed control, the output mosfet usually has its gate with a pull-down resistor to source to keep it off; and the PWM square wave source is fed into the gate with usually a small value resistor in series.
If the PWM signal source has a capacitor at its output, would that ensure the Mosfet would never stay on if the PWM source fails and stays 'high' ?
Is it a common practice to feed signal into a mosfet gate trough a capacitor ? Why ?
Say pin 5 with a series capacitor in this random example borrowed from the web:
----> https://www.circuitstoday.com/wp-content/uploads/2010/01/speed-control-for-PCB-drill.png