SG3525A Pulse Width Modulator Control Circuit
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 onchip +5.1 V reference is trimmed to ±1% and the error amplifier has an input commonmode 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 CT and Discharge pins. This device also features builtin softstart circuitry, requiring only an external timing capacitor. A shutdown pin controls both the softstart circuitry and the output stages, providing instantaneous turn off through the PWM latch with pulsed shutdown, as well as softstart recycle with longer shutdown commands. The under voltage lockout inhibits the outputs and the changing of the softstart capacitor when VCC is below nominal. The output stages are totempole 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 offstate.
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16 PDIP16 N SUFFIX CASE 648 16 1 A WL YY WW = Assembly Location = Wafer Lot = Year = Work Week 1 SG3525AN AWLYYWW
