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Is There A Relay That Triggers At 1.5v?

Hello, i would like to modify circuit to light up an LED when a button is pressed.
My Theory:
When a button is pressed the return Signal wire from the button will become live and IF that wire is connected to a coil in a relay it should trigger a separate circuit
Problem: the buttons on my circuit are like TV remote buttons and use two pads on the PCB and a conductor on the button
these are low voltage so the Signal cable only carries about 1.5V. i haven’t found a relay capable of triggering at 1.5v
so. how can i get an led to light up simultaneously when i press a button without effecting the signal line voltage too much

4 Responses to “Is There A Relay That Triggers At 1.5v?”

1. Mark G Says:
   November 12th, 2009 at 2:50 am

   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

2. . Says:
   November 12th, 2009 at 7:17 am

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

3. Dave D Says:
   November 12th, 2009 at 1:19 pm

   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.

4. natchomo Says:
   November 12th, 2009 at 3:13 pm

   You could use a SSR, Solid state relay.

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