I am using a MOSFET with a remote control momentary switch to turn a 1.5v mini DIY motor, which in turn controls the movement of a tiny plastic mouth to simulate speaking.   My issue is this.....the MOSFET I have calls for DC 3v-5v powersupply.   When I use 3v, the battery drains very quickly.   I've found no such thing as a SMALL 5v battery in the U.S., so I switched to 6v and it works just fine, but I am worried I will damage the MOSFET.   Here is the spec info from the seller (we are using Version A - DC3v-DC5v). 

Product Description

1. Working Voltage: A: DC3V-DC5V     B: DC3.5V-DC12V  Optional 


 2. Max Load: 1A (have better load less than 700ma)

 3.  Working Frequency: 433.92MHz

  Working Current / Quiescent current : 7ma/H

 4. Frequency Deviation: more or less than 0.2MHz

 5. Working temperature:  -20'C- +80'C

 6. Receiving Sensitivity: ≥-110dBm

 7. Output State: A: Input DC3V-DC5V  Output DC3V-DC5V 

Did you consider using a proper driver circuit for the gate instead of just messing with the voltages?
Or just a stable but strong enough 5V for the gate, like using a voltage regulator or zener diode?
Driving a mosfet correctly for the application in question will keep it happy and cool ;)

croswords (author)  Downunder35m1 month ago

I have to admit.....we know NOTHING about electronics, so "proper driver
circuit for the gate", zener diode", etc. might as well be a foreign
language where we're concerned. We're building a magic prop and all the
gizzards have to fit into a 2"x3"x1" box, which means we're running out
of room in there for additional components. We've gotten as far as we
have by quite frankly bumbling around, and miraculously have a working
prop. We simply couldn't understand why the 3v batteries for the
Mosfet were draining so fast....which is why we switched to the 6v. Has
been working fine so far, since the motor is only operating in short
spurts via the momentary switch to make the "mouth" move. Just weren't
certain about damaging the Mosfet by doing what we're doing. Our next
move I suppose will be to install a small "kill switch" for the battery
and see if a 3v will quit draining under those circumstances. I
greatly appreciate your time in answering, and I apologize if we wasted
your time a bit by not first explaining that we are total novices.