Analog comparator - voltage limit == iref?

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Hi,
What is the maximum voltage input value possible with the analog comparators on the AVR?

For example, is it possible to accurately compare voltage==+15.35 on the postitive AIN0 to voltage==+15 on AIN1 for the ATtiny45 without frying anything? What is the maximum voltage?

Or...

must the AIN0/AIN1 voltages be dropped to below 5v or internal reference w/ resistors?

thanks for any and all replies.

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Quote:

must the AIN0/AIN1 voltages be dropped to below 5v ...

As far as I know, that would be true (if your Vcc is 5V).

Quote:
Absolute Maximum Ratings
Voltage on any Pin except RESET with respect to Ground ................................-0.5V to VCC+0.5V

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.

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Quote:
Absolute Maximum Ratings
Voltage on any Pin except RESET with respect to Ground ................................-0.5V to VCC+0.5V

I promise on a stack of Bibles, I searched the datasheet and googled for that gem, and missed it.

but I still wonder if someone could squeeze the voltage up a bit and get away with it.

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I think it wouldn't work... Make yourself a voltage divider out of 2 resistors. 4 to 1 should work.

---
Formerly Torby. Stitch626 just seemed a more descriptive nicname.

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Quote:

but I still wonder if someone could squeeze the voltage up a bit and get away with it.

Three words: port protection diodes.

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.