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PowerInt 公司的LinkSwitch-PH系列集成了725V功率MOSFET,连续模式PWM控制器,用于自偏置的高压开关电流源,频率抖动,逐个周期的电流限制以及延迟热关断电路,大大地简化PF大于0.9, TRIAC调光的LED驱动器的设计,主要用在离线led驱动器.本文介绍了LinkSwitch-PH系列主要特性,功能方框图, TRIAC调光14W 和7W LED驱动器电路图,以及TRIAC调光14W LED驱动器参考设计主要指标,电路图和材料清单.The LinkSwitch-PH dramatically simplifies implementation of LED drivers requiring PF >0.9, TRIAC dimmer capability and high efficiency. The single-stage PF and constant current controller ELiminates passive circuitry required for power factor correction and electrolytic bulk capacitor. The advanced primary-side control techniques used by the LinkSwitch-PH device provide accurate constant current control while eliminating the need for an optocoupler and secondary-side currentฌ control circuitry.LinkSwitch-PH incorporates a 725ค V power MOSFET, a continuous-mode PWM controller, a high voltage switched current source for self biasing, frequency jittering, cycle-by-cycle current limit and hysteretic thermal shutdown circuitry, all in a monolithic IC. LinkSwitch-PH系列主要特性:Dramatically Simplifies Off-line LED Drivers ? Flicker-free phase-controlled TRIAC dimming? Single stage power factor corrected and accurate constant current output? Eliminates optocoupler and all secondary current control circuitry? Eliminates all control loop compensation circuitry? Simple primary-side PWM dimming ฑinterface? Universal input voltage range? Enables designs that are electrolytic-freeAccurate and Consistent Performance? ☹ Compensates for transformer inductance tolerances? Compensates for line input voltage variations? Frequency jittering greatly reduces EMI filter size and coดstsAdvanced Protection and Safety Features? Auto-restart for short-circuit protection? Open circuit fault detection mode? Automatic thermal shutdown restart with hysteresis? Meets high vo