I am driving a 12VDC 2A motor with a MOSFET h-bridge, where with the same ground i have the 7805 voltage regulator connected. Now when the motor is active, the h-bridge is draining approx 0.2V to ground. This is causing the 7805 IC output to increase to approx 5.2V.
Is it normal that the h- bridge leak some voltage to ground ?? if yes, how can i prevent the 0.2V from going to the 7805 ground pin ??
Can you post a schematic? The 7805 should be referenced to ground. If the ground reference is elevated of the 7805 the output voltage will elevate. There is something to your circuit I am just not seeing.
It sounds like what you have is a voltage drop on your ground line - and a big one. Move the ground for the H bridge to the point where the main power supply comes in and make your measurements from that same point. Make sure your wires are big enough for 2 amps.
Hi, thanks for the replies. Attached is the diagram of the H-bridge with the list of components used. The other diagram shows how the 7805 ground is connected to the h-bridge.
So it is not normal to have voltage leak to ground when the motor is on ??
The 7805 is supplying the PIC, LCD and other ICs. The motor is being supplied from a bench top power supply. The only thing that the H-bridge and the 7805 are sharing is the ground.
I am driving a 12VDC 2A motor with a MOSFET h-bridge, where with the same ground i have the 7805 voltage regulator connected. Now when the motor is active, the h-bridge is draining approx 0.2V to ground. This is causing the 7805 IC output to increase to approx 5.2V.
Is it normal that the h- bridge leak some voltage to ground ?? if yes, how can i prevent the 0.2V from going to the 7805 ground pin ??
The 7805 is supplying the PIC, LCD and other ICs. The motor is being supplied from a bench top power supply. The only thing that the H-bridge and the 7805 are sharing is the ground.
Is there a kind of a filter which keeps the ground to 0V??