I need a couple transistors or mosfets or something for a project I’m working on. I know a bit about electronics and schematics but not enough to calculate and find what I need; That’s why I’m consulting an electronics forum. I’m looking for part numbers that I could just order online. The first part I need, needs to be able to switch ground on and off for a 12v solenoid(there’s already a constant +12v going to the solenoid, so i need to switch the ground). when activating the solenoid, it can draw up to an amp but when its just holding the solenoid open, its only about .5 amp. I imagine this would be some kind of transistor or mosfet(honestly, i don’t know the difference). I also need another similar part that generates a PWM signal @ 292.5Hz 0-50% duty cycle for a pwmSolenoid (Again, there’s already constant +12v going to the solenoid, so I need to switch the ground). The amperage criteria for this is a little confusing for me, but apparently the average current draw at 50% dc for this solenoid is about 1 amp(maybe there’s no need to be confused and we can just say 1amp, I don’t know that much). So like I said, I’m hoping to get part number(s) (I’m not sure if I’d just be able to use the same part for both applications). If I cant get part numbers, then I’m at least looking for a start on what to look for or who to talk to. Any help is appreciated. thanks!
For the one that just switches on / off - Easiest to use an NPN bipolar transistor. It will need a resistor between whatever drives it and the Base, to limit the current to a safe level. Pick a transistor with at least 1.5Amp Ic, and 50Vce. You will need a 1 amp 50V diode across the solenoid winding also, to dissipate the inductive kick when the transistor turns off. The temperature range this has to operate in may also matter.