MOSFET switch, open circuit with capacitor?

[Gabsbiz]

Hi,

NEWBIE ALERT

I'm trying to use a MOSFET as a switch. I've been successful when using an arduino because it provides both a negative to close and positive to open.

I want to use a MOSFET switch without needing an arduino. Getting the switch to close is simple enough, by providing power, but how do I open the circuit again? Simply removing power does not close the circuit.

I thought about using a small capacitor that would provide a tiny amount of positive after battery power was removed, but my research left me confused and doubtful this would work.

Any tips or ideas?

Cheers,

Gabriel

[KMoffett]

What's the load you're switching on and off? Switching what voltage and current? Which MOSFET?
If you're doing low-side switching with an N-MOSFET and just removing power from the gate, there is still a charge on the gate that keeps the MOSFET in conduction. If so, just add a 10K resistor between the gate and source to discharge the internal gate-source capacitance.

Ken