| 简介 |
Power Integration 公司的TOPSwitch-HX系列是高性价比的电源解决方案，它集成了700 V 功率 MOSFET，高压开关电流源，PWM控制器，振荡器，热关断电路，故障保护和其它控制电路，广泛应用于各种AC/DC转换电源。本文介绍了TOPSwitch-HX系列的主要性能特点，方框图以及典型反馈电路和多种AC/DC转换电源电路。
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.
TOPSwitch-HX主要特性：
Lower System Cost, Higher Design Flexibility
Multi-mode operation maximizes efficiency at all loads
New eSIP-7C package builds on PI’s experience with high power and high reliability packages
Low thermal impedance junction-to-case (2 °C per watt)
Low height is ideal for adapters where space is limited
Simple mounting using a clip to aid low cost manufacturing
No heatsink required up to 35 W using P, G and M packages with 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 (254Y-258Y and all E packages) reduces transformer and power supply size
Half frequency option for video applications
Frequency jittering reduces EMI filter cost
Heatsink is connected to SOURCE for low EMI
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
Extended creepage between DRAIN and all other pins improves field reliability
EcoSmart®– Energy Effi cient
Energy efficient over entire load range
No-load consumption
Less than 200 mW at 265 VAC for TOP256-258
Less than 300 mW at 265 VAC for TOP259-261
Standby power for 1 W input
>600 mW output at 110 VAC input
>500 mW output at 265 VAC input
图1. TOPSwitch-HX 功能方框图 (P和G 封装)
图2. TOPSwitch-HX 功能方框图 (M 封装)
图3. 采用光耦TL431反馈电路的TOPSwitch-HX 反馈电源电路
图4.采用TOP258PN 通用输入的 35 W电源电路
图5.典型的齐纳反馈电路
图6.典型的光耦TL431反馈电路
图7.采用TOP258PN 35 W双输出电源电路.
图8.采用TOP258YN 150 W, 19.5 V 电源电路
图9.通用输入20 W连续功率 80 W峰值功能电源电路
图10.采用TOP260EN 65 W, 19 V 电源电路
来源：中电网 |
