W83321G

The W83321S is a high-speed, N-Channel synchronous buck regulator controller. The W83321S employs fixed-frequency voltage-mode PWM control architecture. Both high-side and low-side MOSFETs are lower cost N-Channel type. The regulator is biased from a 5V rail and the power for the high-side MOSFET can be supplied by a separate 12V rail or supplied from a local charge pump.

Current limit is achieved by monitoring the voltage drop across the on resistance of the low-side MOSFET. This method eliminates the requirement of extra current sensing resistor and avoids false trigger of OC protection when VIN varies. The adaptive non-overlapping MOSFET gate drivers help avoid potential shoot-through problems while maintaining high efficiency.