The UC1525B pulse width modulator integrated circuit is designed to offer improved performance and lowered external parts count when used in designing all types of switching power supplies. The on-chip 5.1-V buried zener reference is trimmed to ±0.75%, and the input common-mode range of the error amplifier includes the reference voltage, eliminating external resistors. A sync input to the oscillator allows multiple units to be slaved or a single unit to be synchronized to an external system clock. A single resistor between the CT and the discharge terminals provide a wide range of dead-time adjustment.