UCC2894DR集成电路（IC）的ACDC转换器离线开关规格书PDF中文资料

UCC2894DR属于集成电路（IC）的ACDC转换器离线开关。由德州仪器制造生产的UCC2894DRAC DC 转换器，离线开关该系列是元器件级控制产品，用于构建将交流市电转换为直流电（通常电压大幅降低）的设备。集成和未集成系统主要开关元件的器件均包括在内。由于高输入输出电压比，以及此类系统中通常需要隔离，这些器件通常与外部变压器配合使用。尽管通常使用定制变压器来实现此用途，但也有许多专门用于此用途的库存产品，请参见“开关转换器，SMPS 变压器”标题。

FEATURES

Low Output Jitter

Soft−Stop Shutdown of MAIN and AUX

Ideal for Active Clamp/Reset Forward,

Flyback Converters

Provides Complementary Auxiliary Driver

with Programmable Deadtime (Turn-On

Delay) between AUX and MAIN Switches

Peak Current-Mode Control with

Cycle-by-Cycle Current Limiting

110-V Input Startup Regulator on UCC2891/3

TrueDrive 2-A Sink, 2-A Source Outputs

Accurate Line UV and Line OV Threshold

Programmable Slope Compensation

1.0-MHz Synchronizable Oscillator

Precise Programmable Maximum Duty Cycle

Programmable Soft Start

APPLICATIONS

150-W to 700-W SMPS

High-Efficiency, Low EMI/RFI Off-Line or

DC/DC Converters

Server, 48-V Telecom, Datacom

High Power Adapter, LCD-TV and PDP-TV

DESCRIPTION

The UCC2891/2/3/4 family of PWM controllers is

designed to simplify implementation of the various

active clamp/reset switching power topologies.

The UCC289x is a peak current-mode, fixedfrequency,

high-performance pulse width modulator.

It includes the logic and the drive capability for the

auxiliary switch with a simple method of

programming the critical delays for proper active

clamp operation.

The UCC2891/3 includes a 110-V start-up

regulator for initial start-up and to provide

keep-alive power during stand-by.

Additional features include an internal

programmable slope compensation circuit,

precise DMAX limit, and a single resistor

programmable synchronizable oscillator. An

accurate line monitoring function also programs

the converter’s ON and OFF transitions with

regard to the bulk input voltage. Along with the

UCC2897, this UCC289x family allows the power

supply designer to eliminate many of the external

components, reducing the size and complexity of

the design.