1326Views8Replies

Author Options:

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

8 Replies

user
steveastrouk (author)2014-09-12

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

Steve

Select as Best AnswerUndo Best Answer

user

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.

Select as Best AnswerUndo Best Answer

user

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

Select as Best AnswerUndo Best Answer

user

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

Select as Best AnswerUndo Best Answer

user

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

Select as Best AnswerUndo Best Answer

user

What current do the LEDs take ?

Select as Best AnswerUndo Best Answer

user
mpilchfamily (author)2014-09-11

Sure you can run it off coil cells.

Select as Best AnswerUndo Best Answer