Circuit needed to trigger an LED ! ! !

Can any one suggest me a circuit that would trigger a LED for less than a second. The trigger would be a passive infra-red sensor.

What do you mean by "trigger"? (Do you mean turn on the LED for 1 sec?)
What is a "passive infra-red sensor"?

MikeMl said:

What do you mean by "trigger"? (Do you mean turn on the LED for 1 sec?)
What is a "passive infra-red sensor"?

Click to expand...

hi think he want to keep the LED lit less than a sec. i too have no idea about the second one.

I'm guessing He said he wants to use the output from a PIR sensor to trigger a 1-second timer to drive an LED. Maybe.

THere's a circuit here https://www.futurlec.com/PIR_D203B.shtml for interfacing to a bare PIR device; it has a relay output (which you can precede with your 1 second timer). If you already have a PIR module (with the control circuits), then the 1 second timer connects to the output of that.

For the 1 second timer, you can use a number of things, but the most often quoted device to use seems to be the 555.