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 +5.1V 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 dead time
can be programmed by a single resistor connected between the CT 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 VCC 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.
Specification:
- 8.0 V to 35 V Operation
- 5.1 V 1.0% Trimmed Reference
- 100 Hz to 400 kHz 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: 400 mA Peak
- Pb−Free Packages are Available*
Package Includes :
1x IC SG3525 KA3525 PWM Controller IC 16-DIP