PWM Current Mode Power Amplifier
Original Publication Date: 1985-Jun-01
Included in the Prior Art Database: 2005-Feb-18
A pulse-width modulated (PWM), current-mode power amplifier provides low power dissipation and linear current energization of a DC motor. A reduction in the number of amplifier components, the physical size of the amplifier, and the amplifier cooling requirements results. By using the inductive nature of a DC motor, a square wave of voltage can be impressed on the motor terminals, and the resulting motor current ramps up and then decays at current turnoff. By controlling the current "on" time, and by sensing the current which flows through the motor, a feedback circuit is configured such that the current through the motor is servo-controlled to be proportional to a control input voltage "Vin".