GENERAL DESCRIPTION

The ML4411 provides complete commutation for delta or wye wound Brushless DC (BLDC) motors without the need for signals from Hall Effect Sensors. This IC senses the back EMF of the three motor windings (no neutral required) to determine the proper commutation phase angle using Phase Lock Loop techniques. This technique will commutate virtually any 3-phase BLDC motor and is insensitive to PWM noise and motor snubbing. The ML4411 is architecturally similar to the ML4410 but with improved braking and brown-out recovery circuitry.

FEATURES

■ Back-EMF commutation provides maximum torque for minimum “spin-up” time for spindle motors

■ Accurate, jitter-free phase locked motor speed feedback output

■ Linear or PWM motor current control

■ Easy microcontroller interface for optimized start-up sequencing and speed control

■ Power fail detect circuit with delayed braking

■ Drives external N-channel FETs and P-channel FETs

■ Back-EMF comparator detects motor rotation after power fail for fast re-lock after brownout