SparkFun Forums

[Jassper]

I can't seem to find the min/max voltage value that can be applied to the RAW pin on the Arduino Pro Mini board.

[signal7]

Well, the schematic is no help since they chose not to label U2. If I were guessing (and I am), it looks to be a voltage regulator of some kind. The home page for the pro mini says that the input voltage shouldn't exceed 12V. I think if you put 12V on Vcc, you would indeed let the magic smoke out, so I think that spec only applies to the RAW input pin.

[Jassper]

Right, If I know what U2 was, I could look up the specs for the voltage reg. I will be useing 5v for some other things, so I can feed 5v on the vcc pin, but would rather use the RAW pin if I can.

I will get my microscope and see if I can get the numbers off the V-reg.

Thanks for the reply.

EDIT
The description for the part mentions, DC input 5V up to 12V but most 5v regs can handle up to 18 volts so I don't thin this is definite.

[AZRobbo]

The Vreg on the board says "KB50", and the KB is underlined.

Hopefully you can determine the make/model from that.

[FartingMonkey92]

FYI, that is a MIC5205-5.0YM5 from Micrel...
Relevent datasheet: http://www.micrel.com/_PDF/mic5205.pdf

[Jassper]

FYI, that is a MIC5205-5.0YM5 from Micrel...
Relevent datasheet: http://www.micrel.com/_PDF/mic5205.pdf

Excellent, Thanks !

[Ragnorok]

- Old topic, but same question ... info on the regulator on the sparkfun Arduino Pro Mini. Why start a new thread?

- My question is this: the datasheet linked to by FartingMonkey92 does appear to be correct. Thanks! But that datasheet says the regulator will accept up to 16v, not the 12v that's listed everywhere for the Pro Mini board. Is that because the caps won't take it, or can it really be run from 16v?

- Reason is I want to run this Pro Mini off a car battery, which puts out more like 13.5v when fully charged. I'd rather avoid doing pre-regulation for the regulator. (grin) I'm not worried about dissipation because if the datasheet is correct it tells how to determine the that sort of thing.

Thanks for your time...

- Rags

[davegior]

bump for answer, please

[davegior]

I was thinking of using two 3.7v li-ion batteries in series for 7.4v - 8.4v on the Raw pin. Does anyone see a problem with that?
I'm building a project that will be powered by the li-ion batteries and would power a DC-DC step down converter and output (adjustable) 3.5v to 6.0v that would feed a resistance load of 2.0 ohms. I would like to avoid building a separate 5v regulator for the mini pro