Apply a 20ma (max) 5v signal to a line. When that gets applied, switch turns on and lets 12V to flow through.
Here's a little diagram:
Basically the TRIGGER i have is 5v 20ma and when i apply that to it, i want to activate the switch between IN and OUT (to basically allow that to flow).
The IN i need either a 12/24V DC or AC, or 120V AC.
No, the 5v/20ma (well 25ma MAX to be more exact) is the output from a pin on a PIC16F688 microcontroller. I want to use that output to controll a door strike module. So the 5v would be applied whenever the door needs to be "opened".
Maybe i didnt explain this right. I want the switch to CLOSE as long as i apply the trigger to it, and be left open otherwise.
Well, the details help us to help you.
So you need a one shot, I think, triggered by the microcontroller.
Pulse has to be long enough for the door mech. to do it's job.
Or the pulse width is controlled by the microcontroller?
I was thinking of making my own "switch" with a transistor and applying that 5v/20ma to the gate But i started simulating and it started to get more and more complicated... figured a relay or switch pre-build would be easier.
I can work with either. Theres a few latches there that work with 12/24 AC OR DC and a few that work with 120V AC. I really dont care what latch i use, as long as it works with my setup.
This relay fires up at 3.75V, dies at 1V. TTL levels are 0-0.8V for a low (relay off), 1.8V-5V for a high (relay on at 3.75).
CMOS is based on the Vdd you're driving the chip at. A low is <= 45% of Vdd, a high is greater than 45% Vdd. So, with CMOS, if your Vdd is 5V, a low is anything less than 45% of 5V (0-2.25V), a high is anything higher than 2.25V.
A PIC is TTL and CMOS compatible, so if you are using a Vdd of 5V, you're good to go. If you're using 3.3V or less, you're up the river.