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 effectivy 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
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Low cost, low component count and small PCB footprint solution
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Performance met without synchronous output rectification
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132 kHz operation optimized core size and efficiency performance
?
Low-profile eSIP package
Integrated Protection and Reliability Features
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Line under-voltage lock out (UVLO)
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Primary sensed latching output overvoltage shutdown (OVP) with fast AC reset
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Auto recovery output over current (OCP)
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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 ).
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
详情请见:
http://www.powerint.com/sites/default/files/product-docs/topjx_family_datasheet.pdf
和
http://www.powerint.com/sites/default/files/PDFFiles/der246.pdf