原标题：PowerInt TOP265EG 30W待机电源参考设计

　　powerint 公司的TOPSwitch-JX系列(TOP264-271)集成了725V功率MOSFET,高压开关电流源,多模式PWM控制,热关断电路,故障保护和其它控制电路, 265 VAC电压下无负载的功耗低于100mW.本文介绍了TOPSwitch-JX系列(TOP264-271)主要特性, 方框图, 通用输入高效19V 65W反激电源电路图和采用TOP265EG的12V 30W高效待机电源设计案例的电路图和所用材料清单.

　　TOPSwitch-JX TOP264-271 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.

　　TOPSwitch-JX 系列主要特性:

　　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)

　　• 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.TOPSwitch-JX系列功能方框图(E 和V 封装).

　　图2.TOPSwitch-JX系列通用输入高效19V 65W反激电源电路图

　　采用TOPSwitch-JX系列TOP265EG的12V 30W高效待机电源设计案例

　　12V 30W设计案例主要特性:

　　Highly energy efficient

　　Full load efficiency >90%

　　Efficiency >87% above 10% load

　　Average efficiency >90% (25%, 50%, 75%, 100% load points)

　　No-load input power <100 mW

　　Simplifies meeting ENERGY STAR 2.0, 80 Plus and EuP requirements

　　725 V MOSFET rating allowed high turns ratio (VOR) and use of 60 V Schottky output diode

　　Low cost, low component count and small PCB footprint solution

　　Performance met without synchronous output rectification

　　132 kHz operation optimized core size and efficiency performance

　　Low-profile eSIP package

　　Integrated Protection and Reliability Features

　　Line under-voltage lock out (UVLO)

　　Primary sensed latching output overvoltage shutdown (OVP) with fast AC reset

　　Auto recovery output over current (OCP)

　　Meets limited power source (LPS) <100 VA requirement with a single point of failure

　　Accurate thermal shutdown with large hysteresis

　　图3.设计案例PCB外形图(2.97 x 2.14 吋).

　　设计电源指标:

　　图4. 12V 30W设计案例电路图

　　设计案例材料清单:

　　图5. 12V 30W设计案例变压器电框图