SCR latching circuits and LEDs Answered
LEDs and I just can get along...In another project I had a solenoid blowing out LEDs. Now this: I have a number of switches hooked up so they trigger an SCR latching circuit to turn on (and keep on) some LEDs. The SCRs are wired in parallel to each other and have a 1K resistor on the gate. Power is applied to the whole circuit via a timer relay (not hooked to the SCRs). The power is a 12v, 200mA wall wart. And the SCRs I'm using are NTE 5465. The LEDs last a while but burn out or go to a weird blinking state (when the switch is depressed) after about 2-3 days. In my previous project I needed a diode to help with the solenoid voltage spike. But I don't think that it is the case for this project since the SCRs aren't inductive. Do LEDs connected to the switch part of a relay need a diode too? The LED package I'm using is purchased from Happ Controls (see hideous grainy picture). It's rated for 12V but they can't give me a mA rating on them. But they say that no inline resistor is required. Any thoughts? I think this is another case of my inexperience causing me to overlook the obvious.