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Topic: Push button toggle switch, old style (Read 1164 times) previous topic - next topic

Push button toggle switch, old style

Hi all,

I recently answered a question about how a specific circuit worked and I was so intrigued that I just needed to write down my findings and share it.

The circuit uses a single (cheap) push-button to make the output toggle with debouncing and no-delay switching. The circuit used originally two NOR-gates and was embedded in a mixer-table. I boiled the circuit down a bit to get to the bottom and this is the result:

The original NOR-gates were used to be able to do predictable power-up behavior as well as global set/reset functionality. The elegance of the circuit is brilliant IMO.

A full write-down and timing-diagram is on my homepage at Have fun looking and enjoying pre-microcontroller era ingenuity.