I have bought this H-bridge from Robotpower and want to connect it to the Arduino. Robot Power Products - Simple-H & HV - H-bridge
I have connected 12 volt from a bench type power supply to the H-bridge board and then connected two pwm output from the Arduino board to the H-bridge inputs. The Arduino takes it power supply from the USB connection.
Does this work or do I have to connect the two grounds from the Arduino and the H-bridge also? What can happen if I don't do that? Scared of switching the power on before knowing this.
Always connect the grounds.