NCP1252

Current Mode PWM Controller for Forward and Flyback Applications NCP1252 The NCP1252 controller offers everything needed to build cost− effective and reliable ac−dc switching supplies dedicated to ATX power supplies. Thanks to the use of an internally fixed timer, NCP1252 detects an output overload without relying on the auxiliary Vcc. A Brown−Out input offers protection against low input voltages and improves the converter safety. Finally a SOIC−8 package saves PCB space and represents a solution of choice in cost sensitive project. Features  Peak Current Mode Control  Adjustable Switching Frequency up to 500 kHz  Jittering Frequency 5% of the Switching Frequency  Latched Primary Over Current Protection with 10 ms Fixed Delay  Delay Extended to 150 ms in E Version  Delayed Operation Upon Start−up via an Internal Fixed Timer (A, B and C versions only)  Adjustable Soft−start Timer  Auto−recovery Brown−Out Detection  UC384X−like UVLO Thresholds  Vcc Range from 9 V to 28 V with Auto−recovery UVLO  Internal 160 ns Leading Edge Blanking  Adjustable Internal Ramp Compensation  +500 mA / –800 mA Source / Sink Capability  Maximum 50% Duty Cycle: A Version  Maximum 80% Duty Cycle: B Version  Maximum 65% Duty Cycle: C Version  Maximum 47.5% Duty Cycle: D & E Versions  Ready for Updated No Load Regulation Specifications  SOIC−8 and PDIP−8 Packages  These are Pb−Free Devices Typical Applications  Power Supplies for PC Silver Boxes, Games Adapter...  Flyback and For...