latchswitchestransistors
I need to build a soft latching on-off-on switch that latch with momentary push buttons for use in on a 220v AC power line.
I mean a switch that have three momentary push buttons (2 buttons for on state and one for off state).
Is there a schematic for this?
Thanks
I'm not an expert, but I think your problem is your weak 1M pullup R3. Until your soft latch switches on, the load circuit will be acting as a pull down through that 100k and it might keep the gate low.
Depending on the requirements you could use a latching mosfet circuit as shown below. The first time you push the button M1 is turned on, the second time you push the button it is turned off.
When the circuit is off it does not consume power (other than leakage of the mosfet).
simulate this circuit – Schematic created using CircuitLab
Best Answer
Use simple relay logic. It will be simplest possible solution. If you get 220VAC relays, it can be made without additional power supply (sorry, the graphical symbols are not very good):
simulate this circuit – Schematic created using CircuitLab