When my BBB arrived in a while, I intend to modify it for use with 3.3V circuits. One of the obvious choice is to replace the voltage regulator, 7805, with a 3.3V version. Are there any recommendations here? What are the considerations here (e.g. output current, input voltage range, package, cost, anything else)?
Any other options beside replacing voltage regulator? What are the pro and cons for different options?
For 3.3V operation, I probably also need to use a slower crystal, say 12MHz. Any other considerations that I have left out?
Cheers
3.3V IO
Re: 3.3V IO
Ben,
You have the main issues under consideration (v.r. and clock speed). The 168s and 328 chips seem to run fine at 16Mhz - but they're not quite rated for it - so there is some issue that Atmel ran into. I haven't tracked down what this was yet. (Where the speed derating curve comes from).
We're clocking the JeeNodes at 16 Mhz, and running on 3.3V and we haven't seen any major issues yet. So I guess this depends on how conservative you want to be with things like reliability. It could be a borderline issue with some temperatures or reliable startup - or other issues that don't immediately come to mind.
Paul
You have the main issues under consideration (v.r. and clock speed). The 168s and 328 chips seem to run fine at 16Mhz - but they're not quite rated for it - so there is some issue that Atmel ran into. I haven't tracked down what this was yet. (Where the speed derating curve comes from).
We're clocking the JeeNodes at 16 Mhz, and running on 3.3V and we haven't seen any major issues yet. So I guess this depends on how conservative you want to be with things like reliability. It could be a borderline issue with some temperatures or reliable startup - or other issues that don't immediately come to mind.
Paul