I am controlling 2 DC motors (Cytron SPG30E - 150k w/ encoder and Cytron SPG30-60k) with a L298 Dual H-Bridge DC Motor Controller, bought at RobotShop (http://www.robotshop.com/eu/en/l298-dual-h-bridge-dc-motor-controller.html).
I have 2 power supplies, one for 5v (control) and one for 12V (power supply the motors), with their common ground connected.
The controller works fine but whenever SPG30E-150K is moving, my 5V power supply is affected by noise. The same doesn't happen with the other dc motor.
Do you know what might be cause of this noise and how to prevent it?