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TI 公司的TPS92070是用于低功率離線LED照明的先進的PWM控制器，具有先進的調光接口，提供無損耗調光觸發控制電路。沒有低頻光照度波動，LED電流調整度優于5%，并可編最小LED電流，功率因素大于0.8。TPS92070集成了PWM MOSFET驅動器和熱關斷電路，主要用在LED照明燈，LED燈光源，LED聚光燈和LED投光燈。本文介紹了TPS92070主要特性，功能方框圖，應用框圖以及TPS92070EVM-648評估板主要特性，電路圖和材料清單。 The TPS92070 is an advanced PWM controller ideal for use in low-power, offline, LED lighting applications. The integrated dimming interface circuit of the TPS92070 features a non‐dissipative dimmer trigger control circuit. The TPS92070 controller provides DC LED current with no photometric ripple effects. The DC current also results in higher efficacy of the LEDs. The TPS92070 provides exponentially controlled light output based on the external dimmer position. High power factor is achieved with a valley fill circuit. Once a leading-edge dimmer is detected, the TPS92070 sets an output to disable the PFC circuit and thus optimizes driver operation. The LED current sense precision error amplifier implements deep dimming. TPS92070主要特性： Advanced Integrated Dimming Interface Non-Dissipative TRIAC Dimmer Management Lamp-to-Lamp Uniformity During Dimming No Low-Frequency Photometric Ripple Exponential Dimming Profile Innovative Secondary-Side Feedback Eliminates Optocoupler Devices LED Current Regulation better than 5% Programmable Minimum LED Current Valley Switching and DCM Operation for Reduced EMI and Improved Efficiency Leading Edge Dimmer Detection Power Factor > 0.8 Cycle-by-Cycle Current Limit Protection Low Start-Up and Standby Currents Integrated PWM MOSFET Driver Thermal Shutdown 16-Pin, TSSOP package TPS92070應用： LED Light Bulb Replacement LED Luminaires LED Downlights LED Wall Washers 
圖1。TPS92070功能方框圖
圖2。TPS92070應用框圖 TPS92070EVM-648評估板 The TPS92070EVM-648 evaluation module (EVM) is a low power isolated flyback converter that provides 5 on-board LEDs with 370 mA of drive current from a nominal 230 VAC input. This EVM is designed to demonstrate the TPS92070 in a typical application where LEDs can be used for general illumination applications that require dimming. This evaluation module uses the TPS92070 High Efficiency Integrated Dimming LED Lighting Driver Controller (TI Literature Number SLUSAN1) in a low power offline flyback converter to provide 370 mA to the on-board LED load. The input accepts a nominal 50 Hz, 230 VAC input voltage. The TPS92070EVM-648 is designed to be used with a leading edge triac dimmer switch in series with the input voltage to control the lumen output of the LEDs. The integrated dimming interface circuit on the TPS92070 provides exponentially controlled light output based on the external dimmer position. This user’s guide provides the schematic, component list, assembly drawing, and test set up necessary to evaluate the TPS92070 in an AC input LED lighting application. To use an input voltage greater than 240 VAC, it is recommended the user change the fuse to one rated for at least 300 V at 1 A. TPS92070EVM-648評估板主要特性： • 180 VAC to 240 VAC input range • LED current regulation of 370 mA, nominal • 6 W output at 16.5 V • Advanced integrated dimming interface • Exponential dimming profile • Programmable minimum LED Current • Valley switching and DCM operation • Leading edge dimmer detection • Valley fill power factor correction • Cycle by cycle current limit protection TPS92070EVM-648評估板電性能指標：
圖3。推薦的TPS92070EVM-648評估板測試圖
圖4。TPS92070EVM-648評估板電路圖 TPS92070EVM-648評估板材料清單：
詳情請見： 
slusan1.pdf
(814.29 KB)
sluu523.pdf
(2.84 MB)
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