Click to expand full text
July 2000
ML4423* 1, 2, or 3-Phase Variable Speed AC Motor Controller
GENERAL DESCRIPTION
The ML4423 provides the PWM sinewave drive signals necessary for controlling three phase AC induction motors as well as single and two phase split capacitor AC induction motors. A constant voltage/frequency ratio can be maintained over a frequency range of greater than 10:1, providing 15Hz to 150Hz control. The output variable frequency AC voltages are sensed and fed back to the controller to track the sinewave frequency and amplitude set at the speed control input. Direction, on two and three phase motors, is controlled by changing the relative phase difference between the motor windings: 90× for two phase motors and 120× and 240× for three phase motors.
ML4423 Datasheet
