12v DC Gear Motor Control + L9110S Driver + Arduino Uno

Other Hardware Motors, Mechanics, Power and CNC
1

I'm working on a project where I control a 12V 5RPM geared motor using an Arduino UNO and the L9110S driver. I'm using the following connection diagram (image attached):

  • Digital pins 8 and 9 of the Arduino are connected to A-IA and A-IB of the L9110S.
  • The motor is connected to Motor A+ and A– of the module.
  • The GND of the driver is connected to the GND of the Arduino.
  • The VCC of the driver is connected to the VIN of the Arduino UNO.

My main question is:
How should I correctly supply 12V power to this circuit?

And is it correct to supply the Arduino through the jack or through VIN with a 12V transformer, and from there bridge it to the VCC of the driver?

Thank you for your help and collaboration.

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2

Let's turn it like this: Is there a sense to pass the motor supply through arduino?
Tmho there's not.

Why don't you split the supply for both of them or power them separately (if desired)?

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3

Actually you can use one of the wall warts that supply 12V DC. A transformer outputs AC which you will have to convert to DC before using. Be sure it will supply at least enough to support the motor inrush current and the Arduino. Extra current will not cause problems. @kmin suggestion to split power is a good place to start.

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4

Thank you very much for your response, although I have more questions now, I am sending you a representative diagram of the circuit now connecting the transformer (AC/DC 12V up to 3A), avoiding direct connection to the Arduino, can I get it to work without burning the driver?I was afraid to make it work because two drivers burned out when trying to insert 12V.

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5

Use a separate power supply for the Arduino, but be sure to connect the Arduino and motor driver GNDs.

The L9110 driver is designed to work only with very small toy motors, and is likely to fail with a more powerful gearmotor. Please post the motor specifications.

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6

On your last pic arduino doesn't have supply GND at all!
If your power supply has that screw connector like on your imagine, wire both 12V / GND from there both to arduino and to motor driver. Avoid using breadboard for "high current" supply.

2 Likes
7

No.
The drivers are half of an infamous L293D and maybe just OK for tiny toy motors.
12volt is absolute max for these drivers 9volt would be safer.
They struggle with 800mA motor current. A gear motor is far beyond their capability.
Leo..

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