Power Integrations公司的TOPSwitch-HX系列是成本效益器件,在单个器件内集成了700V功率MOSFET,高压开关电流源,PWM控制,振荡器,热关断电路,故障保护以及其它控制电路.通用交流电压输入,在不加散热器的情况下,输出功率可高达35W,待机输入功率1W时的输出功率,在110V AC时大于600mW,而在265V AC输入时大于500mW.本文介绍了该系列中的TOP254-258系列的主要性能特点,以及进行开关电源设计所需的材料,包括各种应用电路图。

TOP254-258 TOPSwitch-HX Family
TOPSwitch-HX cost effectively incorporates a 700 V power MOSFET, high voltage switched current source, PWM control, oscillator, thermal shutdown circuit, fault protection and other control circuitry onto a monolithic device.

产品亮点:

Lower System Cost, Higher Design Flexibility
Multi-mode operation maximizes effi ciency at all loads
No heatsink required up to 35 W using P, G and M packageswith universal input voltage and up to 48 W at 230 VAC
Output overvoltage protection (OVP) is user programmable for latching/non-latching shutdown with fast AC reset
Allows both primary and secondary sensing
Line undervoltage (UV) detection prevents turn-off glitches
Line overvoltage (OV) shutdown extends line surge limit
Accurate programmable current limit
Optimized line feed-forward for line ripple rejection
132 kHz frequency (Y package) reduces transformer and power supply size
Half frequency option in Y package for video applications
Tight I2f parameter tolerance reduces system cost
Maximizes MOSFET and transformer power delivery
Minimizes overload power, reducing cost of transformer,primary clamp and secondary components
Frequency jittering reduces EMI fi lter cost
Improved auto-restart delivers <3% of maximum power in short circuit and open loop fault conditions
Accurate hysteretic thermal shutdown function automatically recovers without requiring a reset
Fully integrated soft-start for minimum start-up stress
Pin-out simplifi es heatsinking to the PCB for P, G and M packages
Extended creepage between DRAIN and all other pins improves field reliability
Heatsink is connected to SOURCE for low EMI
Energy efficient over entire load range
No-load consumption <200 mW at 265 VAC
Standby power for 1 W input
>600 mW output at 110 VAC input
>500 mW output at 265 VAC input



图1.采用Opto/TL/431反馈的TOPSwitch-HX反激电源方框图.



图2a.P和G封装的TOP254-258功能方框图.



图2C.Y封装的TOP254-258功能方框图.



图2b.M封装的TOP254-258功能方框图.



图3.采用TOP258PN的35W双输出电路图.



图4.采用TOP258YN的150W,19.5V电源电路图.



图5.采用TOP258MN的20W(连续),80W(峰值)通用输入电源电路图.




图6.采用TOP258PN的通用输入35W电源电路图.

详情请见:

http://www.powerint.com/PDFFiles/tophx_family_datasheet.pdf

和应用手册

http://www.powerint.com/PDFFiles/an43.pdf

来源：中电网