基于TOP266EG的27W LCD監視器電源設計方案

Powerint 公司的TOPSwitch-JX 系列TOP266EG是高性價比器件，它集成了725V　功率MOSFET，高壓開關電流源，多模式PWM控制，振蕩器，熱關斷電路，故障保護以及其它控制電路．265 VAC時無負載的功耗低于100 mW，工作頻率132 kHz，降低了變壓器尺寸和電源的體積．本文介紹了TOPSwitch-JX 系列主要特性，產品亮點，功能方框圖，以及65W 19V和30W 12V通用輸入反激電源電路圖，27W LCD監視器電源參考設計主要指標，電路圖以及所用材料清單(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產品亮點：

? 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

圖１．TOP266EG 功能方框圖(E和V封裝)

圖２．采用TOP266EG的65W 19V通用輸入反激電源電路圖

圖３．采用TOP266EG的30W 12V通用輸入反激電源電路圖

27W LCD監視器電源設計方案

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.


圖４．27W LCD監視器電源參考設計外形圖

27W LCD監視器電源參考設計指標：


圖５．27W LCD監視器電源參考設計電路圖

圖６．參考設計中的變壓器電方框圖

27W LCD監視器電源參考設計材料清單（ＢＯＭ）：




圖７．27W LCD監視器電源參考設計ＰＣＢ布局圖