The H-bridge gets its name from its four-transistor configuration — it appears as an "H" on a schematic diagram. A DC motor is located in the middle of the horizontal bar of the H in the example given ...

and DC motor specially in our case 775 12V DC motor draws 0.45Amps if we connect it directly to arduino board you know what happen, it will burn your arduino board. for such purpouse we are going to ...

We can control the speed of the DC motor using a TIP20 NPN Power Transistor, ... In this project we can control the speed of the DC motor using a TIP20 NPN Power Transistor, D1M4004 Rectifier Diode, ...