[#004 Pushbutton switch for LED] Use a NE555!

[steveschnepp]

I actually had the exact same need. But didn't want to leverage a full MCU, a full Arduino even less 😉

So, I designed a schmitt trigger based one. Yet some search on the internet unearthed a NE555 based solution. Which is great as a DIP-8 is a smaller footprint as the DIP-14 from a CD40106. And using a NE555 for something is always nice 😂

A nice side effect of the schmitt trigger is that there's an automatic debouncing included, as depending on the capacitor and resistor values one cannot click too fast.

The trick is that the NE555 is also used as a schmitt trigger like my solution. I inverted the resistor values in my design, in order to consume less current (battery-powered). So a long press will actually keep toggling the output.

Here's the link to the NE555 one : https://www.electronics-lab.com/project/toggle-on-off-switch/

Mine is highly similar, but using a CD40106 and having 2x 1M resistors with a 47k one filling a 22uF capacitor. I used the other invertors in parallel to drive the LED with more current.

Funnily, I finally settled for a NE555 but I had to lower the resistors otherwise it was too glitchy. 😂