Comments on: Is There A Relay That Triggers At 1.5v?

By: natchomo

natchomo — Thu, 12 Nov 2009 15:13:04 +0000

You could use a SSR, Solid state relay.

By: Dave D

Dave D — Thu, 12 Nov 2009 13:19:35 +0000

Here you go:-http://search.digikey.com/scripts/DkSear…
But I would use a transistor, not a relay because of the curent requirement of the coil.

By: .

Thu, 12 Nov 2009 07:17:12 +0000

You could use a 741 or transistor as a comparator circuit to drive the relay.

By: Mark G

Mark G — Thu, 12 Nov 2009 02:50:30 +0000

Paine is close.. Use a transistor but don’t bother using a relay.
have the transistor turn on the LED. The transistor is used like a switch. The power is attached to the LED which it then attached to the collector of the transistor (you may also need a series resistor to limit current). The emitter is grounded.
The circuit is then activated by applying voltage to the base of the transistor. The voltage applied to the base come from one of your small switches.http://www.allaboutcircuits.com/vol_6/ch…
The advantage to this is you can swicth larger voltages with a smaller one. Or use a single larger voltage source to power the LED and connect to the low voltage switch. You limit the switch current with a resistor