simple power control chip

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#1
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This should be an easily available chip but I don't seem to think of the right search term. I want a device that turns the power on/off to my AVRs on pressing a button and has a pin which when pulled high turns off the power. I know there are lots of ways to do it but I just want an easy one chip solution. TIA.

Ralph Hilton

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It's unclear to me exactly what you want, but this will power up your AVR with a push-button if you have the extra port pin. You would still need some way to tell the AVR to power itself off.

Note: The required bypass caps are not shown.

Tom

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Some commercially available equipment has a button to push for power on/off and a timeout where it turns off after a certain time of not being in use. That's the functionality I want. I'd need to use an AVR pin to tell it when to turn off.

Ralph Hilton

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What about the diode inside the fet? Should it be otherway around?

Regards
heguli

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Ralph--you can also look for regulators with a /SHUTDOWN pin that the AVR can control to power itself off, and then the external button can be used to power up again.

Now, that type of regulator probbably uses a few uA when in shutdown. Hmmm--new AVR V & P chips use only a couple of uA when in PWOERDOWN, and a number of different wakeup sources can be enabled. So just keep that AVR running... :)

Lee

You can put lipstick on a pig, but it is still a pig.

I've never met a pig I didn't like, as long as you have some salt and pepper.