I have a need to run a custom board at 5v. The issue is the board needs an xBee as well. I'm pretty sure the xBees only run on 3v3 so I'm wondering about talking between the two. (Just the serial lines are needed)
The AVR (ATmega128) datasheet says that the Input High Voltage needs to be above 0.6 VCC to read. 5v * .6 = 3V. Can I thus just use the xBee output directly into the input pins? Or is it really worth throwing a small transistor with a couple pull-ups
In the opposite direction, I was just gonna use a voltage divider but it would be nice to just drive the 3v3 inputs with 5v. Anyone know if you can just drive the xBee with 5v? Will it hurt it? I can't find any electrical characteristics for the xBee.