ML4423

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 of ML4423 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 of ML4423 , 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.

To protect the motor, power devices, high voltage drivers and control circuitry, the ML4423 includes fixed period, pulse by pulse variable duty cycle current limit, deadtime circuitry, and undervoltage lockout. The ML4423 has selectable output voltage swing of 5V or 12V for interfacing to different high side drivers and power devices.