UC1525B-SP Datasheet | Texas Instruments

SLUS874 - JANUARY 2009 RAD-TOLERANT CLASS-V REGULATING PULSE WIDTH MODULATOR Features - QML-V Qualified, SMD 5962-89511 - Rad-Tolerant: 30 k Rad (Si) TID (1) - 8-V to 35-V Operation - 5.1-V Buried Zener Reference Trimmed to ±0.75% - 100-Hz to 400-k Hz Oscillator Range - Separate Oscillator Sync Terminal - Adjustable Deadtime Control - Internal Soft Start - Pulse-by-Pulse Shutdown - Input Undervoltage Lockout With Hysteresis - Latching PWM to Prevent Multiple Pulses - Dual Source/Sink Output Drivers - Low Cross Conduction Output Stage - Tighter Reference Specifications (1) Radiation tolerance is a typical value based upon initial device qualification with dose rate = 10 mrad/sec. Radiation Lot Acceptance Testing is available - contact factory for details. DESCRIPTION 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 mon-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. These devices also feature built-in soft-start circuitry with only an external timing capacitor required. A shutdown terminal controls both the soft-start circuitry and the output stages, providing instantaneous turn off through the PWM latch with pulsed shutdown, as well as soft-start recycle with longer shutdown mands. These functions are also controlled by an undervoltage lockout which...