Electronic – 1 pulse toggle with simple non programmable electronics

passive-componentstoggle switch

I need to create a simple circuit that toggles when one pulses a push button and then stays on no matter what you do with the push button again. The toggle will reset when the system is powered off (starts off)

Any clues where to start from ? I've playing with relays,push buttons and those but .. cannot really get it. I'm currently working with logic gates to see where it leads..

Any idea ?

Best Answer

This is actually quite simple to do with a single SPST relay:

schematic

simulate this circuit – Schematic created using CircuitLab

This is completely generic. The power source can be AC or DC. The only requirements are:

  • Both the switch and the relay contacts must be rated to handle the load current.
  • The relay coil must accept the same power (AC or DC, same voltage) as the load.

When you push the button, power is applied to both the load and the relay coil. After that, the relay contacts keep the current flowing until the power source is removed.

I once built a high-power version of this to run all of my computer systems. I was living in an area that was subject to bursts of short-term power outages. Since computers and other electronic gear don't particularly like to be "short cycled" like this, I used the circuit to make sure that once the power went off, it stayed off. I would restart everything manually by pushing the button, once the power had settled down again.