TI公司的TPS92551是恒流降壓LED驅動微型模塊,最大驅動電流450mA,功率23W,能驅動多達16個LED/串.器件集成了包括電源指示器的所有功率元件,電源效率高達95%,輸入電壓4.5V-60V,LED電流從300mA到450mA可調整,開關頻率800kHz,主要用在通用照明如臺燈,裝飾燈,街燈,建筑照明如水下照明,壁龕照明和聚光燈等.本文介紹了TPS92551主要特性和封裝亮點,方框圖,典型應用電路和相應的材料清單,評估板PCB布局圖. The TPS92551 Constant Current Buck LED Driver Micro-Module drives maximum 450mA LED current up to 16 LEDs in a single string (maximum 23W). It integrates all the power components including the power inductor. The TPS92551 provides a full turn-key, highly efficient solution for wide range of single string LED lighting applications with up to 95% power efficiency. It accepts an input voltage ranging from 4.5V to 60V and delivers a 350mA LED current as default. The LED current is adjustable from 300mA to 450mA by charging a single external resistor. The module operates at constant switching frequency (800kHz) with low Electro Magnetic Interference(EMI) complying with EN55015 standard. The module has fast control loop to realize fine LED current pulse yielding 256–step PWM dimming resolution at 240Hz for general lighting. Protection features include thermal shutdown, input under-voltage lockout, LED open-circuit and short-circuit protections. The TPS92551 Micro-Module is available in TO-PMOD 7 pin power package. TPS92551封裝亮點: ■ 7 lead easy-to-use package (Similar to TO-263) ■ Single exposed die attach pad for enhanced thermal performance 10.2 x 13.8 x 4.6 mm package TPS92551主要特性: ■ Integrated all power components including the power inductor ■ Wide input voltage range : 4.5V - 60V ■ Constant switching frequency at 800kHz ■ High contrast ratio (Minimum dimming current pulse width < 16μs) ■ Drives up to 16 LEDs in series at 60V input ■ ÷3.5% typical LED current accuracy ■ LED current adjustable from 300mA to 450mA ■ Up to 95% efficiency ■ Input Under-Voltage Lock-Out (UVLO) ■ Compatible with ceramic and low ESR capacitors ■ Low Electro Magnetic Interference (EMI) complies with EN55015 standard ■ LED open and short circuit protections ■ Thermal shutdown and RoHS compliant ■ -40˚C to +125˚C junction temperature range TPS92551應用: ■ General Lighting Desk Lamps Cabinet Lamps Decorative Lamps Street Lamps ■ Architecture Lighting Recess Lights Spot Lights Underwater Lights 圖1.TPS92551方框圖 圖2.TPS92551典型應用電路圖: VIN = 48V, ILED = 350mA, LED數量 = 5 –13 圖2材料清單: 圖3.TPS92551典型應用電路圖: VIN = 60V , ILED = 350mA , LED數量= 16 圖3材料清單: 圖4. TPS92551EVM評估板外形圖 圖5. TPS92551EVM評估板PCB布局圖:頂層 圖6. TPS92551EVM評估板PCB布局圖:底層 詳情請見: 和 |