Arduino Pro Mini 5v with RN41 Bluetooth module

Wireless & IoT
1

Hi All,

Currently wiring up an circuit for my 5v arduino to work with the Roving Networks RN41 bluetooth module.

Need an little help working the wiring out as ive hit an little snag.

List of Kit:

Arduino 5v Pro Mini

RN-41 module (not the Breakout)

3.3v Voltage regulator

FTDI basic breakout - 5v

What im doing is connecting the FTDI board to the Arduino, Then taking the 5v, Ground, RX and TX over to the RN41.

In between the FTDI board 5v and the RN41 VCC is the Voltage regulator.

Now for the problem. The voltage regulator is getting extremely hot, I mean hot enough to melt glue from an hot glue gun. All other components are working fine, but no power to the RN41. Any ideas

Before you ask, i’ve checked that the regulator is wired in the right way from the schematics.

Would it be doing this if im powering it from an 5v 1A supply to the FTDI board by any chance?

2

Remove the RN-41 and make sure that you’re really getting 3.3V from the voltage regulator. If not, make sure that 5V are really going into it. If one or the other of those isn’t working, you need to troubleshoot that separately from the RN-41 attachment.

A hot voltage regulator in that situation sounds like some kind of short to me.

You might also think about removing the Arduino and running a 5V source into your voltage regulator setup to make sure that you can get 3.3V out that way.

If all of that is working without the RN-41 attached then I’d suspect a short somewhere in how you’re attaching that.