基于TOP266EG的27W LCD监视器电源设计方案

TOPSwitch-JX 系列TOP266EG是高性价比器件，它集成了725V　功率MOSFET，高压开关电流源，多模式PWM控制，振荡器，热关断电路，故障保护以及其它控制电路．265 VAC时无负载的功耗低于100 mW，工作频率132 kHz，降低了变压器尺寸和电源的体积．本文介绍了TOPSwitch-JX 系列主要特性，产品亮点，功能方框图，以及65W 19V和30W 12V通用输入反激电源电路图，27W LCD监视器电源参考设计主要指标，电路图以及所用材料清单(BOM)．

Power Supply Using TOP266EG

90 VACC265 VAC Input; 5V, 2.5A and　14.5V, 1A Outputs

Application LCD Monitor

TOPSwitch-JX cost effectively incorporates a 725 V power MOSFET, high voltage switched current source, multi-mode PWM control, oscillator, thermal shutdown circuit, fault protection and other control circuitry onto a monolithic device.

TOP266EG产品亮点：

EcoSmart® - Energy Efficient

Energy efficient over entire load range

No-load consumption below 100 mW at 265 VAC

Up to 750 mW standby output power for 1 W input at 230 VAC High Design Flexibility for Low System Cost

Multi-mode PWM control maximizes efficiency at all loads

132 kHz operation reduces transformer and power supply size

66 kHz option for highest efficiency requirements

Accurate programmable current limit

Optimized line feed-forward for line ripple rejection

Frequency jittering reduces EMI filter cost

Fully integrated soft-start for minimum startup stress

725 V rated MOSFET

Simplifies meeting design derating requirements Extensive Protection Features

Auto-restart limits power delivery to 3% during overload faults

Output short-circuit protection (SCP)

Output over-current protection (OCP)

Output overload protection (OPP)

Output overvoltage protection (OVP)

User programmable for hysteretic/latching shutdown

Simple fast AC reset

Primary or secondary sensed

Line undervoltage (UV) detection prevents turn-off glitches

Line overvoltage (OV) shutdown extends line surge withstand

Accurate thermal shutdown with large hysteresis (OTP) Advanced Package Options

eDIP-12 package:

Low profile horizontal orientation for ultra-slim designs

Heat transfer to both PCB and heat sink

Optional external heat sink provides thermal impedance equivalent to a TO-220

eSIP®-7C package:

Vertical orientation for minimum PCB footprint

Simple heat sink mounting using clip provides thermal impedance equivalent to a TO-220

Extended creepage to DRAIN pin

Heat sink is connected to SOURCE for low EMI

图１．TOP266EG 功能方框图(E和V封装)

图２．采用TOP266EG的65W 19V通用输入反激电源电路图

图３．采用TOP266EG的30W 12V通用输入反激电源电路图

27W LCD监视器电源设计方案

This document is an engineering report describing a 5 V / 2.5 A, 14.5 V / 1 A power supply utilizing a TOP266EG. The TOP266EG is part of the TOPSwitch-JX IC family from Power Integrations. The document contains the power supply specification, schematic, bill of materials, transformer documentation, printed circuit layout, and performance data.


图４．27W LCD监视器电源参考设计外形图

27W LCD监视器电源参考设计指标：


图５．27W LCD监视器电源参考设计电路图

图６．参考设计中的变压器电方框图

27W LCD监视器电源参考设计材料清单（ＢＯＭ）：




图７．27W LCD监视器电源参考设计ＰＣＢ布局图