vielle568
Member
Can someone please give me some advice on how to drive a relay from the output of a 556 dual timer. I have configured both halves of the 556 in monostable mode to put out a single short pulse; these pulses will then be used to trigger a small 12 volt bistable relay.
The 556 is functioning OK and giving out 1/2 second signal pulses; these are currently powering indicator LEDs. I've tried using these output pulses directly to the relay without success; perhaps the coils are a little too powerful for the IC? I have tried using these output signals to control transistors to drive the relays but without success; the 2N2222A transistors seem to get very hot and burn out; other types (2N2904, BC549, 2N3819) don't seem to work at all.
The 556 and the relay are running on 12 volts from a 7812. If there's a standard means of driving a relay from this IC can someone please explain how it should be done? Thank you.
The 556 is functioning OK and giving out 1/2 second signal pulses; these are currently powering indicator LEDs. I've tried using these output pulses directly to the relay without success; perhaps the coils are a little too powerful for the IC? I have tried using these output signals to control transistors to drive the relays but without success; the 2N2222A transistors seem to get very hot and burn out; other types (2N2904, BC549, 2N3819) don't seem to work at all.
The 556 and the relay are running on 12 volts from a 7812. If there's a standard means of driving a relay from this IC can someone please explain how it should be done? Thank you.