I need a circuit or hints towards making a circuit that is a simple set/reset latch. one that works under the following conditions:
-Set and Reset action from a single input switch
-The input switch goes from float to ground when pressed.
-The latch output needs to rest at Vcc when powered on and idle, and ground when set. back to Vcc when reset, and not grounded with power removed even when the circuit is still grounded.
-Finally, the latch needs to activate when the input goes from float to ground. when the switch is pushed.
I tried this circuit:
But it latches on the input release. No good!
I've got a bunch of transistors, diodes, some 40XX circuits (NANDs and JK flip flops) laying around, and some more. And of course plenty of components.
Supposedly this circuit will do it:
But I hate relays because they are noisy, expensive, and large. I'd be happy to consider this option if I can have a silent relay that takes up less than approx. 1/2"x1/4" of PC boardspace (preferrably much less). I don't have any of those in my project box though...
-Set and Reset action from a single input switch
-The input switch goes from float to ground when pressed.
-The latch output needs to rest at Vcc when powered on and idle, and ground when set. back to Vcc when reset, and not grounded with power removed even when the circuit is still grounded.
-Finally, the latch needs to activate when the input goes from float to ground. when the switch is pushed.
I tried this circuit:
But it latches on the input release. No good!
I've got a bunch of transistors, diodes, some 40XX circuits (NANDs and JK flip flops) laying around, and some more. And of course plenty of components.
Supposedly this circuit will do it:
But I hate relays because they are noisy, expensive, and large. I'd be happy to consider this option if I can have a silent relay that takes up less than approx. 1/2"x1/4" of PC boardspace (preferrably much less). I don't have any of those in my project box though...