is pro mini 3.3V 8Mhz 5v tolerant on IO pins?

Other Hardware 3rd Party Boards
1

Hi, I use a 3.3V arduino pro mini with 8 MHz. Are the inputs 5v tolerant? Can I program it via ISP directly from a nano or uno without 5v / 3v level shifter? VCC of mini will be used by 3.3v

Thanks

2

butch:
Are the inputs 5v tolerant?

No, the datasheet for the ATmega328P is very clear, maximum voltage on a pin is VCC + 0.5V;

You will find the same answer with a Google search.

3

butch:
Hi, I use a 3.3V arduino pro mini with 8 MHz. Are the inputs 5v tolerant? Can I program it via ISP directly from a nano or uno without 5v / 3v level shifter? VCC of mini will be used by 3.3v

Thanks

What you can do is disconnect any other power from the board and connect a 5v ISP programmer, with Vcc to the Vcc pin of the Pro Mini as usual and program it. In this case, the whole board will be running at 5v during the programming process. Which is fine - as long as it's powered at 5v on the Vcc pin and isn't connected to another power source.

Just be sure to not have it connected to anything that isn't 5v tolerant while doing this.

4

A good ISP programmer, like the truly excellent Pololu V2.1, senses the target processor voltage and switches output voltage accordingly.

Highly recommended.

5

jremington:
A good ISP programmer, like the truly excellent Pololu V2.1, senses the target processor voltage and switches output voltage accordingly.

Highly recommended.

Very +

You can slow it right down so it works with less than ideal wiring.

6

thanks for the replies. I took a second 3.3v arduino and used it as isp programmer. worked like charme