I am having difficulty in finding a suitable half bridge driver and power mosfet combination to enable me to design a throttle actuator control module. I have trawled the internet for circuits etc from several manufactures of bridge driver ic's but have not found any that do what I want. Most half bridge drive / power mosfet configurations show single rail supply and motor drive in one direction only. I am trying to design a drive module for control of a standard car wiper motor, these DC brush motors have the one brush connected to the frame, i.e. earth/ground. The standard circuits in data sheets and application notes show either a full bridge having 'floating' motor connections or half bridge from single supply referenced to ground giving only one diection 'speed' control. I have not designed using mosfet drivers etc and the problem is trying to find a driver and mosfet combination that will work correctly from a positive and negative rail supply. The problem for me is how the low side driver is configured to work from a negative rail and not referenced to ground but typically a minus 30V rail. I have been unable to find a circuit design that shows the biasing nessecary to drive the output mosfets both positive and negative in a servo loop with the motor having a position feedback pot as closed loop control.
I have attached a simple drawing that shows what I am after. Can you advise a suitable mosfet driver chip and power mosfets combination and any documenation that would enable me to produce a pcb for my application. I will need several of these and hope to to have a product line available for the egine test market.
Best regards
Vic Oliver
Votec Systems7120.TH OP DESIGN Model (1).pdf
