Toggle power on and off (standby) with a momentary switch

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Hello,

I'm looking for instructions/tips on how to set up one momentary switch to toggle power from 'on' to a low current standby mode ('off' to folk who don't know better) - this is for an atmega16 circuit.

I'm not sure what search terms to use though, hard to search for !

Any hints or just the name if any of this setup/mode appreciated.

:wink:

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At the semiconductor manufacturers the terms are:
Push Button Controller
Push Button Controllers
On/Off Controller
ON/OFF Power Control
There are at least several circuits that do this if one does not want to use a does-all IC.

"Dare to be naïve." - Buckminster Fuller

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'soft' power up. What do you want to switch?
note that 'off' and low power standby are two different things.

The mega16 is not the best choice for low current standby - you really want a pinchange interrupt to wake the cpu.

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I'm assuming that this is a battery powered application ?

In the past, I have used a low Q current D type flip flop configured as a T type to toggle when clocked. The PB switch was connected to the clock input of the latch through a RC filter. Every time the switch is depressed, the latch toggles. The output of the latch is connected to a MOSFET to control power to the rest of the circuit.

An old style CD4013 has a very, very low Q current in static mode, so it draws nearly nothing from the battery while it "waits". But it's in a SO14 package, so it's fairly large. More modern single latches are available (like the 74AUP1G374GW,125), but Q current is higher. You can do some shopping around to find one to meet your needs.