SD42351 350MA WHITE SINGLE LED DRIVER DESCRIPTION The SD42351 is a low dropout current regulator rated for constant LED sink current. The low quiescent current and low dropout voltage is achieved by advanced Bi-CMOS process. FEATURES * No external component required. * Fixed 110mA, 150 mA, 170 mA, 215 mA, 245mA, 270mA, 305mA, SOT-89-3 335mA sink current. * Output short / open circuit protection. * Low dropout voltage. * Low quiescent current * Build-in thermal protection APPLICATIONS * Supply voltage range 3V ~ 6V * 2KV HBM ESD protection * 1W Power LED driver * Advanced Bi-CMOS process. ORDERING INFORMATION Package SOT-89-3 Type Seal Current Value (Typical) (mA) SD42351NA 351A 335 SD42351NB 351B 305 SD42351NC 351C 270 SD42351ND 351D 245 SD42351NE 351E 215 SD42351NG 351G 170 SD42351NH 351H 150 SD42351NL 351L 110 HANGZHOU SILAN MICROELECTRONICS CO.,LTD Http: //www.silan.com.cn REV:1.5 2008.03.13 Page 1 of 5 SD42351 BLOCK DIAGRAM ABSOLUTE MAXIMUM RATINGS (Tamb=25°C) Characteristics Symbol Rating Unit Max Supply Voltage VDD(max) 6 V Min Supply Voltage VDD(min) 3 V Tamb 0 ~ + 70 °C Tst -40 ~ +150 °C Operating Temperature Storage Temperature ELECTRICAL CHARACTERISTICS (Unless otherwise specified, Tamb=25°C, IOUT=335mA) Characteristics Supply Voltage Range Quiescent Current Output Current Current Line Regulation Dropout Voltage Symbol Test condition Min. Typ. Max. Unit VDD -- 3 -- 6 V IQ -- -- 160 200 uA 3V≤VIN≤6V 320 335 350 mA 3V≤VIN≤6V -- 2.08 -- %/V I=335mA,Measured at VOUT -- 120 -- mV IOUT ΔIOUT ΔVIN * IOUT Vdropout Power NMOS Leakage Ileak VOUT＝5V -- 0.1 1 μA Thermal Shut-down Temp Tj(sd) -- -- 140 -- °C Shut-down Temp Hysteresis Thyst -- -- 20 -- °C HANGZHOU SILAN MICROELECTRONICS CO.,LTD Http: //www.silan.com.cn REV:1.5 2008.03.13 Page 2 of 5 SD42351 PIN CONFIGURATION PIN DESCRIPTION Pin No. Pin Name I/O Pin Description 1 VOUT O LED Current Output. 2 GND -- Ground . 3 VDD I Power Supply. FUNCTION DESCRIPTION The SD42351 is a low dropout current regulator rated for constant LED sink current. The low quiescent current and low dropout voltage is achieved by advanced Bi-CMOS process. Its main function is to stabilize the current passing, other than the LED voltage. Traditional LED drivers are Voltage regulator IC, which will affect the brightness because of different forward voltages, although the LEDs are in the same structure. SD42351 controls the brightness of the LED by controlling the current passing by the LED, which eliminates the limitation of traditional voltage regulator IC. The device consists of Voltage Reference, Error Amplifier, Power NMOS, Current Sense Resistance, LOGIC Enable and Over Temperature Protection Circuit. The resistance senses the output current and transform to the voltage, which compared with the reference voltage. The error is amplified, controls the Power NMOS, so that the output current is regulated. Inrush current (over 1 A) in traditional LED drivers is eliminated by the initial current limit circuit, thus constant sink current in the LED is maintained. TYPICAL APPLICATION CIRCUIT Note:The circuit and parameters are reference only, please set the parameters of the real application circuit based on the real test . HANGZHOU SILAN MICROELECTRONICS CO.,LTD Http: //www.silan.com.cn REV:1.5 2008.03.13 Page 3 of 5 SD42351 PACKAGE OUTLINE SOT-89-3 HANGZHOU SILAN MICROELECTRONICS CO.,LTD Http: //www.silan.com.cn UNIT: mm REV:1.5 2008.03.13 Page 4 of 5