基于TOP265EG設(shè)計(jì)的30W待機(jī)電源方案

TOPSwitch-JX系列(TOP264-271)集成了725V功率MOSFET,高壓開(kāi)關(guān)電流源,多模式PWM控制,熱關(guān)斷電路,故障保護(hù)和其它控制電路, 265 VAC電壓下無(wú)負(fù)載的功耗低于100mW.本文介紹了TOPSwitch-JX系列(TOP264-271)主要特性, 方框圖, 通用輸入高效19V 65W反激電源電路圖和采用TOP265EG的12V 30W高效待機(jī)電源設(shè)計(jì)案例的電路圖和所用材料清單.

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


圖1.TOPSwitch-JX系列功能方框圖(E 和V 封裝).
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圖2.TOPSwitch-JX系列通用輸入高效19V 65W反激電源電路圖

采用TOPSwitch-JX系列TOP265EG的12V 30W高效待機(jī)電源設(shè)計(jì)案例

12V 30W設(shè)計(jì)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


圖3.設(shè)計(jì)案例PCB外形圖(2.97 x 2.14 吋).

設(shè)計(jì)電源指標(biāo):


圖4. 12V 30W設(shè)計(jì)案例電路圖

設(shè)計(jì)案例材料清單:


圖5. 12V 30W設(shè)計(jì)案例變壓器電框圖