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 VAC–265 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[!--empirenews.page--]

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