hey everyone, I'm new here. that's my intro. So to the point. I've got a low power circuit, powered by a max of 4 batteries ranging from aaa to d. My research shows i can expect about 1.5V for each battery (they'll all be in series). I'll probably plan for a max of 3.6V for safe measure because of some lithium's put out 3.6. So what I'm looking for is a low power switch to control the the flow of the batteries. I briefly looked at relays then realized those weren't what i was looking for. then I came across pnp transistor switch. that sounds more like my cup of tea, but the problem that I'm looking at then is a power drain when the switch is on. I'd like to have a relay type effect, by sending a voltage to the switch for it to permanently switch until another charge comes through. I chose a pnp for the default setting of off (0V) to be closed and for the device to be "on". I'd love to hear from you out here to get some feedback and ideas.

 

You need to specify what you're trying to switch, particularly the current it draws, and how fast you need it to switch (eg. 0.01 Hz vs 10k Hz), and what your control signal looks like (voltage, timing, current capacity).

My guess is you'll end up wanting a MOSFET, as these transistors make excellent electronic switches.