ML4425CS

The ML4425CS from ON Semiconductor is a PWM motor controller IC specifically designed for starting and controlling the speed of delta or wye wound Brushless DC (BLDC) motors without the need for Hall Effect sensors. It utilizes a patented Back-EMF commutation technique with a Phase-Locked Loop (PLL) for precise phase sequencing, offering noise immunity and jitterless torque for efficient spin-up.

This controller integrates an onboard speed control loop and constant off-time PWM control for motor current limiting, ensuring maximum efficiency. It features direct FET drive capabilities for 12V motors and can drive high-voltage motors with IC buffers. The device operates within a voltage range of 10.8V to 13.2V and is housed in a 28-SOIC (0.295", 7.50mm Width) surface-mount package, making it suitable for various general-purpose applications.

The start-up sequence, including alignment, ramp, and set speed, is managed onboard. The timing of this sequence can be optimized by selecting external timing capacitors, allowing for adaptation to a wide range of motors and loads. The ML4425CS also includes circuitry to prevent shoot-through in directly driven external power MOSFETs.