Voltage Regulator for PCA9685 board and 7+ volt power supply

In my previous post https://blog.andytriboletti.com/which-servo-motor-im-using-for-my-arduino-project/ I mentioned I had a problem with the servo controller board I was using.

I followed the instructions here:

It says to use a max of 6 volts.

It also says to use -2 x 18650 Li-on Batteries which equal over 7 volts.

Since the board started smoking when the servo was hitting against the wheel, I decided to try a couple different things.

-Write an email to the people who wrote the wiki
-Buy a voltage regulator. I searched Amazon for “Voltage regulator” and found this:
-Stop causing the servo to hit against the wheel by buying a new regulator that didn’t have the problem of moving without instructions.
-Bought a replacement servo controller board. https://smile.amazon.com/SunFounder-PCA9685-Channel-Arduino-Raspberry/dp/B014KTSMLA/

It has a bit less memory than it used to, since some corrupted sectors had to be quarantined?

“…though it has a bit less memory than it used to, since some corrupted sectors had to be quarantined.”

Mars Rover Curiosity is switching brains so it can fix itself

What does that mean?

Which servo motor I’m using for my Arduino project

I purchased 2 different kinds of servo motors for my robot Arduino project.

One on Amazon:


Four on Ebay.

They both arrived quickly.

I tried using the four on Ebay first.

“4PCS Digital MG996R MG995 High Torque Metal Gear Servo For Racing Futaba JR RC”


Eventually the pwm servo driver board I was using started smoking. I sent the people who make the board, SunFounder an email:

“I bought a SunFounder PCA9685 16 Channel 12 Bit PWM Servo Driver for Arduino and Raspberry Pi  on Amazon for 11.99.

I followed the instructions here:


After awhile, the 9685 board started smoking. I was wondering what it could be? I was trying to adjust the min/max of the servo and noticed every time I restarted the power it would rotate a bit in one direction consistently. I think that’s a bug in the software. I Googled and found someone who had the same problem.


I also have this problem:



I was also wondering if the voltage from that wiki page could be too high?


I think without some help if I bought another 9685 board it would just start smoking too and be ruined.


It did work for awhile, but I tried running the example code where you could set the min and max and it knocked up against the metal not being able to move.


I attached a picture. The smoking came from the component to the left of the word power.”
I then bought a new SunFounder PCA9685 servo controller board and tried the one on Amazon. It did not move when I first gave it power, like the one from Ebay.


The ones on Amazon “ANNIMOS 20KG Digital Servo High Torque Full Metal Gear Waterproof for RC Model DIY, DS3218MG,Control Angle 270°” were 4 times more expensive than the Ebay MG 996R ones I found on Ebay, but the DS3218MG works better for my application.

4 wheel drive and 2 distance sensors

My project now has 4 motors and 2 distance sensors. It detects if it will hit something according to its sensors and will head back in reverse.

Powered by 16 AA batteries and 1 9V

I am now waiting on a part from tindie.com in order to connect more ultrasound distance sensors.

Building a robot

I have put some parts together I ordered. It’s using the 2 nasa wheels but different motors and everything else. It is all powered by a 9 volt battery now. I am getting a case for 8 AA batteries to generate 12 volts and I think more available current. Hopefully, that will increase the torque of the 2 motors.