UCC2891中文资料具有 P 沟道钳位 FET 和 0.75V CS 阈值的 110V 有源钳位电流模式 PWM 控制器数据手册TI规格书

描述 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\\x92s 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.

特性 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

简介

UCC2891属于集成电路（IC）的ACDC转换器离线开关。由TI制造生产的UCC2891AC 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。