ON Semi SG3525ANG PWM Voltage Mode Controller Dual 400mA 400kHz

Manufactured by ON Semiconductor - DIP16 Package

Features

• 8.0V to 35V Operation
• 5.1V 1.0% Trimmed Reference
• 100Hz to 400kHz Oscillator Range
• Separate Oscillator Sync Pin
• Adjustable Deadtime Control
• Input Undervoltage Lockout
• Latching PWM to Prevent Multiple Pulses
• Pulse−by−Pulse Shutdown
• Dual Source/Sink Outputs: 400mA Peak

Description

The SG3525A pulse width modulator control circuit offers improved performance and lower external parts count when implemented for controlling all types of switching power supplies. The on−chip +5.1 V reference is trimmed to 1% and the error amplifier has an input common−mode voltage range that includes the reference voltage, thus eliminating the need for external divider resistors. A sync input to the oscillator enables multiple units to be slaved or a single unit to be synchronized to an external system clock.

A wide range of deadtime can be programmed by a single resistor connected between the C_T and Discharge pins. This device also features built−in soft−start circuitry, requiring only an external timing capacitor. A shutdown pin 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 commands. The under voltage lockout inhibits the outputs and the changing of the soft−start capacitor when V_CC is below nominal. The output stages are totem−pole design capable of sinking and sourcing in excess of 200 mA. The output stage of the SG3525A features NOR logic resulting in a low output for an off−state.