I have a fairly simple question, but after looking around online, I’m actually more confused than when I started. What I am trying to do is use a MOSFET as a switch for a very low power (3 V, haven’t measured current, but will be low) circuit. The circuit is from a child’s toy, and takes 2 1.5 V AA batteries.
In the past, I have always used relays when making switches for circuits. However, as I would like to limit the size (and power draw) on the circuit I am building, I would prefer to use a MOSFET.
Previously, I did try to replace a relay in a low power circuit with a 2N222a transistor. However, for reasons I never really understood, I was able to use the 2N222a as a switch to turn LEDs on/off in a test circuit, but when I tried to use it as a replacement for a relay in circuit similar to the one I’m attempting again (3V child’s toy), the toy never actually turned on. Thus, I have two questions:
- In the attached circuit, is there a MOSFET anyone can recommend that may be suitable?
- Is there any reason I can’t use the 2N222A for this circuit? I read this: https://forum.arduino.cc/index.php?topic=212342.0, but then I was a bit confused why it seemed to work fine when simply turning LEDs on/off.
Any answers would be greatly appreciated.