Help! Arduino (s) keeps getting fried // RC Arduino & Motor Shield & DC Motors

Other Hardware General Electronics
1

Hi all you clever people;

here's my setup:

Arduino Uno with L239D Motor Shield mounted on top (This one)

Two different DC Motor connected to the Shield, Motor 1 for driving and Motor 2 for steering.

Everything is Powered by 2200 MAH , 14.8v LiPos and remote-controlled via bluetooth.

I set this up, power it up and it works fine for some minutes. After a while there is a burnt smell and the arduinos LEDs go off. After connecting the Arduino via USB, they turn on again but I'm unable to upload any codes.

Since this is the second time this happened I'd really appreciate any Input! I dont have much knowledge about electronics, so I've got no idea...

Thank you!

2

Those batteries are putting out over 16.5v when fully charged. This is too high for voltage regulator on the arduino.

What maybe happened is the regulator got hotter and hotter until it died. This problem is compounded by the fact the shield on top cuts off a lot of the airflow to the surface of the arduino.

The recommended voltage range to the regulator is 7-12v. Beyond this you will need additional heatsinking.

The usb input provides 5volt power (doesn't use the regulator).
Depending on the heat levels and what happened when the regulator failed, other component may be damaged too.

Just a guess, good luck.

A switching regulator that can safely handle that voltage would be a solution to drop the 16.5v down to 5v.

3

Grrrr you shouldn't post the same question 3 times

4

@alka:

Thanks for your answer! "switching regulator":Do you have a link or an example to where this is used?
Is this soldered on the arduino instead of the existing voltage regulator?
Powering the shield and the arduino sperately sould also do the trick i guess?

@JimboZA
Sorry about that. I posted the question 2 times since i didnt know which topic would "fit"

5

I very well may be wrong.

The regulator should have a thermal shutdown. It should protect itself. Still sounds like thats what failed though.

Powering separately will work too.

6

One cross-post deleted, one cross-post locked.

DO NOT CROSS-POST, CROSS-POSTING WASTES TIME.

If you think you've posted in the wrong place, get a moderator to move it for you.

7

Sorry about the cross-post!

@alka, do you have a link or an example for an extra regulator for the arduino? If possible I'd like to stick to one powersource