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attiny85 on two 3v coin cell batteries? Answered

I've seen specs for attiny85 that say 6v, but most say 5.5v max, so I'm wondering if it's safe to use two 3v coin cell batteries to power them?  Such as CR2032 or CR2450.  I would only use one, but I need 4.5v for my LEDs.  Three AA is too bulky.  Thanks.

Tags:attiny

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steveastrouk
steveastrouk

6 years ago

Why two ? The ATtiny85 runs on as little as 2.7V ! The ATtiny85v will run on 1.8 !

Steve

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aliasjanedoe
aliasjanedoe

Reply 6 years ago

The LEDs it's controlling need 4.5v (I've powered them directly with two 3v CR927 coin cells and they worked beautifully, but the amperage of those is really low, not sure what it is on the larger coin cells).

I breadboard-ed everything with a single CR2032, and also tried two AA, and the lights were much too dim.

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steveastrouk
steveastrouk

Reply 6 years ago

Run two batteries in series, tap the middle, and put the micro across just one battery. That's the safe method.

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aliasjanedoe
aliasjanedoe

Reply 6 years ago

Sorry, I don't understand how this is supposed to work. Can you explain in more detail?

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steveastrouk
steveastrouk

Reply 6 years ago

does this has help?

Sketch136154553.png
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aliasjanedoe
aliasjanedoe

Reply 6 years ago

But my LEDs are connected to the pins of the attiny, which is why I'm confused.

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steveastrouk
steveastrouk

Reply 6 years ago

What current do the LEDs take ?

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mpilchfamily
mpilchfamily

6 years ago

Sure you can run it off coil cells.