LX1554集成电路（IC）的ACDC转换器离线开关规格书PDF中文资料

LX1554属于集成电路（IC）的ACDC转换器离线开关。由美高森美公司制造生产的LX1554AC 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。

DESCRIPTION

The LX155X family of ultra-low start-up current (250µA max.), current mode control ICs offer new levels of energy efficiency for offline converter applications. They are ideally optimized for personal computer and CRT power supplies although they can be used in any number of off-line applications where energy efficiency is critical. Coupled with the fact that the LX155X series requires a minimal set of external components, the series offers an excellent value for cost conscious consumer applications.

Optimizing energy efficiency, the LX155X series demonstrates a significant power reduction as compared with other similar off-line controllers. Table 1 compares the SG384X, UC384XA and the LX155X start-up resistor power dissipation. The LX155X offers an overall 4X reduction in power dissipation. Additionally, the precise oscillator discharge current gives the power supply designer considerable flexibility in optimizing system duty cycle consistency.

KEY FEATURES

■ ULTRA-LOW START-UP CURRENT (150µA typ.)

■ TRIMMED OSCILLATOR DISCHARGE CURRENT (±2 typ.)

■ INITIAL OSCILLATOR FREQUENCY BETTER THAN ±4

■ OUTPUT PULLDOWN DURING UVLO

■ PRECISION 2.5V REFERENCE (±2 max.)

□ CURRENT SENSE DELAY TO OUTPUT (150ns typ.)

□ AUTOMATIC FEED FORWARD COMPENSATION

□ PULSE-BY-PULSE CURRENT LIMITING

□ ENHANCED LOAD RESPONSE CHARACTERISTICS

□ UNDER-VOLTAGE LOCKOUT WITH HYSTERESIS

□ DOUBLE PULSE SUPPRESSION

□ HIGH CURRENT TOTEM POLE OUTPUT (±1Amp peak)

□ 500kHz OPERATION

APPLICATIONS

■ ECONOMY OFF-LINE FLYBACK OR FORWARD CONVERTERS

■ DC-DC BUCK OR BOOST CONVERTERS

■ LOW COST DC MOTOR CONTROL