I would like to make the jaw of a plastic skull open/close based on words spoken by a Raspberry Pi. I can make the Pi send the audio to the headphone jack, and would like to use this output to run 5v dc motor which will open the jaw, and the jaw will close with springs when there is no sound out the audio jack. I already have the jaw setup with motor and springs and it works when 5v applied, now I need the circuit to switch the voltage to the motor. I tried the following suggestion from another question:
"You want an audio level detector".
This worked marginally - the motor was slow to respond and very low speed/power. In another post it was suggested to use a FET, but looking at specs for FETs, I was not able to determine which might work with 5v power, input of less than 2v on gate to turn it fully on, and be able to power the motor which draws up to 350ma.
Can you suggest changes to the existing circuit or provide a circuit/ parts information to use FET for this?