Arduino Pro Mini 3.3V adding power source

Other Hardware General Electronics
1

Hi.
Wondering about how to power the Pro Mini.
Bought this one Arduino Pro Mini 3.3V Retail - RTL-11112 - SparkFun Electronics

I have tried connecting 6 AA batteries or using a single 9V battery to the pins RAW and GND, but the power lamp on the board doesn't light up. This is what I figured I needed to do to make it work when not attached a usb cable.

thx

2

backer:
I have tried connecting 6 AA batteries or using a single 9V battery to the pins RAW and GND, but the power lamp on the board doesn't light up. This is what I figured I needed to do to make it work when not attached a usb cable.

That sounds correct...it should be working.

Do you have anything connected? The regulator on the board is tiny. I can't find a current rating but don't try to power anything more than a few LEDs directly from the board. If you need more milliamps you should probably use an external regulator.

3

Regulator is MIC5205, 150mA.

You could also try 3 AA batteries to VCC & Gnd pins, bypassing the regulator.
I run about 10 of them this way at my fencing club, with 5V from wallwart power the board via Vcc/Gnd pins.

4

backer:
Hi.
Wondering about how to power the Pro Mini.
Bought this one Arduino Pro Mini 3.3V Retail - RTL-11112 - SparkFun Electronics

I have tried connecting 6 AA batteries or using a single 9V battery to the pins RAW and GND, but the power lamp on the board doesn't light up. This is what I figured I needed to do to make it work when not attached a usb cable.

thx

Definitely should be working - my 3V3 has red power LED in centre of board, 4V or more on GND and Raw lights it up. If you don't need the 9V then even just 3 AA's will give enough voltage BTW. Polarity correct?

5

Thanks for the help. Really really appreciate it.

Tried all your suggestions with no luck, different battery amounts, different battery types (none above 12v), polarity, =(
I'm afraid that maybe I broke something when solder the board to a small breadboard?

When connecting the small USB FDTI for programming it lights up so something must be working on the board. Maybe should try as CrossBoards post, using a regulator and connect my power directly VCC port.
Hopefully I can find a regulator tomorrow.

6

You can check if the on-board regulator's working by seeing what voltage appears on the Vcc pin when the Vin pin is
supplied with power - and check if Vin is at the expected voltage too (not shorted).

7

Good tip, checked an no power output on the vcc pin when attached the USB FDTI cable.
So I will order a new Pro mini board and try again.

Thanks all for wonderful help and support.