ML4828

The ML4828 is a complete BiCMOS phase modulation control IC suitable for full bridge soft switching converters. Unlike conventional PWM circuits, the phase modulation technique allows for zero voltage switching (ZVS) transitions and square wave drive across the transformer. The IC modulates the phases of the two sides of the bridge to control output power.

The ML4828 can be operated in either voltage or current mode. Both cycle-by-cycle current limit, integrating fault detection, and soft start reset are provided. The undervoltage lockout circuit features a 1.5V hysteresis with a low starting current to allow off-line start up with a bleed resistor. A shutdown function of ML4828 powers down the IC, putting it into a low quiescent state.

The circuit can be operated at frequencies up to 1MHz. The ML4828 contains four high current CMOS outputs which feature high slew rate with low cross conduction.