Powerint DER-227 3W通用低功耗适配器设计方案

Powerint 公司的DER-227 是采用LinkSwitch-XT 系列LNK362的3W通用低功耗适配器设计案例,输入电压从85V到265AC,3W单输出(5V/0.6A),230VAC时无负载功耗小于10mW,工作模式的效率大于70%, 超过ENERGY STAR v2, EC CoC v4 和EuP Tier 2的规范要求,满足EN55022B/CISPR22B的EMI要求,主要用于手机,PDA,数码相机,MP3/手提音频播放器等充电器/适配器,以及家用电器,工业系统和计量表电源.本文介绍了LinkSwitch-XT 系列主要特性,方框图,典型应用电路以及采用LNK362的2 W 通用输入的CV适配器电路图, 3W通用低功耗适配器详细电路图和材料清单(BOM).

LinkSwitch-XT incorporates a 700 V power MOSFET, oscillator, simple ON/OFF control scheme, a high-voltage switched current source, frequency jittering, cycle-by-cycle current limit and thermal shutdown circuitry onto a monolithic IC. The startup and operating power are derived directly from the DRAIN pin, eliminating the need for a bias winding and associated circuitry.

Product Highlights

Optimized for Lowest System Cost

• Proprietary IC trimming and transformer construction techniques enable Clampless™ designs with LNK362 for lower system cost, component count and higher efficiency

• Fully integrated auto-restart for short circuit and open loop protection

• Self-biased supply – saves transformer auxiliary winding and associated bias supply components

• Frequency jittering greatly reduces EMI

• Meets HV creepage requirements between DRAIN and all other pins both on the PCB and at the package

• Lowest component count switcher solution

Features Superior to Linear/RCC

• Accurate hysteretic thermal shutdown protection –automatic recovery improves field reliability

• Universal input range allows worldwide operation

• Simple ON/OFF control, no loop compensation needed

• Eliminates bias winding – simpler, lower cost transformer

• Very low component count – higher reliability and single side printed circuit board

• Auto-restart reduces delivered power by 95% during short circuit and open loop fault conditions

• High bandwidth provides fast turn-on with no overshoot and excellent transient load response EcoSmart®– Extremely Energy-Effi cient

• Easily meets all global energy efficiency regulations with no added components

• No-load consumption 300 mW without bias winding at 265 VAC input (50 mW with bias winding)

• ON/OFF control provides constant efficiency to very light loads – ideal for mandatory CEC regulations

Applications

• Chargers/adapters for cell/cordless phones, PDAs, digital cameras, MP3/portable audio players, and shavers

• Supplies for appliances, industrial systems, and metering



图1.LinkSwitch-XT功能方框图


图2.LinkSwitch-XT典型应用电路



图3.采用LNK362的2 W 通用输入的CV适配器电路图

3W通用适配器

General Purpose Adapter: 3 W Single Output, <10 mW No-load Consumption, Isolated Adapter Using LinkSwitch-XT

3W通用适配器主要特性:

Universal Input: 85 to 265 VAC

EcoSmart® – Easily meets all current international energy efficiency standards

- China (CECP) / CEC / ENERGY STAR 2 / EU CoC

Extremely low no-load input power consumption: <10 mW at 230 VAC

EC IPP rating of 5 out of 5 stars

High active mode efficiency: >70 %

Exceeds 64% ENERGY STAR v2, EC CoC v4 and EuP Tier 2 requirements

Meets EN55022B/CISPR22B conducted EMI limits without a Y-capacitor across the isolation barrier

This document is an engineering report describing a 5 V, 0.6 A power supply utilizing the LNK363DN (SO8 package) from the LinkSwitch-XT family. It contains the power supply specification, schematic, bill of materials, transformer documentation, printed circuit layout, and performance data.

This design highlights the ultra low no-load input power consumption that is possible when using a LinkSwitch-XT device.



图4.3W通用适配器外形图

图5.3W通用适配器电路图

3W通用适配器材料清单(BOM):




图6.3W通用适配器PCB布局图