Powerint的參考設計DER263是采用LinkSwitchTM-PH系列LNK406EG的14W PWM-模擬調光LED驅動器,LED串的電壓電流為28V/500A,輸入電壓范圍從90VAC到265VAC,高效率,230VAC時的PFC大于87%,115VAC時的PFC大于86%,功率因素大于0.9,滿足EN61000-3-2 Class C,1000:1調光范圍.本文介紹了14W PWM-模擬調光LED驅動器主要特性和指標,電路圖,材料清單與PCB布局圖.
The document describes a high power-factor secondary referenced, analog dimmable LED driver. The circuit is designed to drive a nominal LED string voltage of 28 V at 500 mA from an input voltage range of 90 VAC to 265 VAC. The LED driver utilizes the LNK406EG from the LinkSwitch-PH family of ICs.
Analog dimming is controlled by an external secondary referenced analog control signal of 0-10 V. 0 volts correspond to minimum light output and 10 V corresponds to maximum brightness. The analog controlled signal is transferred to the primary-side and controls the feedback current IFB of LNK406EG which in turn controls the output power/light output of the driver while maintaining high power factor and low THD.
An active load circuit and control are also included to extend dimming ratio beyond 1000:1 but may be omitted if extended dimming operation is not required.
This document contains the LED driver specification, schematic, PCB diagram, bill of materials, conducted EMI measurements, thermal measurements, transformer documentation and typical performance characteristics.
14W PWM-模擬調光LED驅動器主要特性:
High efficiency, power factor corrected
o >87% at 230 VAC and >86% at 115 VAC
o >0.9 PF, meets EN61000-3-2 Class C
0-10 V analog dimming
o >1000:1 dimming range
Low cost, low component count and small printed circuit board footprint
o No current sensing required
o Frequency jitter for smaller, lower cost EMI filter components
Integrated protection and reliability features
o Output open circuit / output short-circuit protected with auto-recovery
o Line input overvoltage shutdown extends voltage withstand during line faults.
o Auto-recovering thermal shutdown with large hysteresis protects both components and printed circuit board
圖1.14W PWM-模擬調光LED驅動器外形圖:上:頂視圖,下:底視圖
14W PWM-模擬調光LED驅動器主要指標:
圖2.14W PWM-模擬調光LED驅動器電路圖
14W PWM-模擬調光LED驅動器材料清單:
圖3.變壓器框圖
圖3.14W PWM-模擬調光LED驅動器PCB布局圖:上:頂層,下:低層
詳情請見:
http://www.powerint.com/sites/default/files/PDFFiles/der263.pdf