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 Forward Converter

NCP1252屬于集成電路（IC） > AC DC 轉(zhuǎn)換器，離線開關(guān)。安森美半導(dǎo)體公司制造生產(chǎn)的NCP1252AC DC 轉(zhuǎn)換器，離線開關(guān)該系列是元器件級控制產(chǎn)品，用于構(gòu)建將交流市電轉(zhuǎn)換為直流電（通常電壓大幅降低）的設(shè)備。集成和未集成系統(tǒng)主要開關(guān)元件的器件均包括在內(nèi)。由于高輸入輸出電壓比，以及此類系統(tǒng)中通常需要隔離，這些器件通常與外部變壓器配合使用。盡管通常使用定制變壓器來實現(xiàn)此用途，但也有許多專門用于此用途的庫存產(chǎn)品，請參見“開關(guān)轉(zhuǎn)換器，SMPS 變壓器”標(biāo)題。