SG1844数据手册集成电路（IC）的ACDC转换器离线开关规格书PDF

描述 Description

The SG1844/45 family of control ICs provides all the required features to implement off-line Fixed Frequency, Current-mode switching power supplies with a minimum number of external components. Current-mode architecture demonstrates improved line regulation, improved load regulation, pulse-by pulse current limiting and inherent protection of the power supply output switch. The Bandgap reference is trimmed to ±1% over temperature. Oscillator discharge current is trimmed to less than ±10%. The SG1844/45 has under-voltage lockout, current-limiting circuitry and start-up current of less than 1mA. The totem-pole output is optimized to drive the gate of a power MOSFET. The output is low in the off state to provide direct interface to an Nchannel device. Both operate up to a maximum duty cycle range of zero to <50% due to an internal toggle flip-flop which blanks the output off every other clock cycle. The SG1844/45 is specified for operation over the full military ambient temperature range of -55°C to 125°C. The SG3844/45 is designed for the commercial range of 0°C to 70°C.Microchip Ordering Part  Standard Microcircuit Drawing (SMD) SG1844F-DESC Cross Reference 5962-8670403HASG1844F-DESC Cross Reference 5962-8670403HXSG1844J-DESC Cross Reference 5962-8670403CASG1844J-DESC Cross Reference 5962-8670403CXSG1844L-DESC Cross Reference 5962-86704032ASG1844L-DESC Cross Reference 5962-86704032XSG1844Y-DESC Cross Reference 5962-8670403PASG1844Y-DESC Cross Reference 5962-8670403PX

特性 Features

Optimized For Off-Line Control
Low Start-Up Current (Automatic Feed Forward Compensation
Trimmed Oscillator Discharge Current
Pulse-By-Pulse Current Limiting
Enhanced Load Response Characteristics -Undervoltage Lockout with 6V Hysteresis
Double-Pulse Suppression
High-Current Totem-Pole Output (1A Peak)
Internally Trimmed Band-gap Reference
500kHz Operation Under-voltage Lockout: SG1844 - 16 volts
Low Shoot-Through Current <75mA Over Temperature

简介

SG1844属于集成电路（IC）的ACDC转换器离线开关。由制造生产的SG1844AC 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。