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by roel_v 2004 days ago
I ordered a few by accident from AliExpress and they showed up yesterday. I don't know for the life of me what to do with them. I was thinking maybe as a temperature/humidity monitor thing, but it would have to be mains powered because I don't think there's a way to make a device like this diy'able (with arduino and dht22 level components) and make it run off a battery for more than a few months. So any suggestions are good.
1 comments
chris_st 2004 days ago
Look into the low-power mode of whatever microcontroller you're using... I did an AT-Tiny85 project, and it burned through the battery. I then switched to low power for a while, and it draws micro-amps (!) when in low-power mode, so the battery would have lasted hundreds of times longer.

Oh... umm... the display, yeah. Maybe have an on-button for the display to power it up only when you want it?

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ISL 2004 days ago
As long as the microcontroller has a sleep mode, you can use a relay (for-real or solid-state) to toggle the power for the display.
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chris_st 2003 days ago
Great idea, thanks!
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