联系人：曹中立 电话：１３４２８７０６２２３ ＱＱ：１１５７００８１１５ 2A 150kHz 40V Buck DC/DC Converter With Constant Current Loop Datasheet XL4001 Features General Description n n Wide 4.5V to 40V Input Voltage Range Output Adjustable from 1.235V to 37V n Minimum Drop Out 1.5V n n n Fixed 150kHz Switching Frequency 2A Constant Output Current Capability Internal Optimize Power Transistor n n n n n Excellent line and load regulation TTL shutdown capability ON/OFF pin with hysteresis function With output constant current loop The XL4001 is a 150KHz fixed frequency PWM buck (step-down) DC/DC converter, capable of driving a 2A load with high efficiency, low ripple and excellent line and load regulation. Requiring a minimum number of external components, the regulator is simple to use and include internal frequency compensation and a fixed-frequency oscillator. n n n Built in thermal shutdown function Built in current limit function Built in output over voltage protection SOP8-EP (Exposed PAD) package The PWM control circuit is able to adjust the duty ratio linearly from 0 to 100%. An enable function, an over current protection function is built inside. An internal compensation block is built in to minimize external component count. Applications n n n Car Charger Battery Charger LED Constant Current Driver Figure1. Package Type of XL4001 Rev 1.2 www.xlsemi.com 1 Datasheet 2A 150kHz 40V Buck DC/DC Converter With Constant Current Loop XL4001 Pin Configurations SW 1 8 VIN SW 2 7 VIN GND 3 6 EN FB 4 5 CS XL4001 Figure2. Pin Configuration of XL4001 (Top View) Table 1 Pin Description Pin Number Pin Name 1,2 SW 3 GND 4 FB 5 CS 6 EN 7,8 VIN Description Power Switch Output Pin (SW). Output is the switch node that supplies power to the output. Ground Pin.(Note: Connected the back exposed PAD to Pin3.) Feedback Pin (FB). Through an external resistor divider network, Feedback senses the output voltage and regulates it. The feedback threshold voltage is 1.235V. Output Current Sense Pin; (Iload=0.155V/Rcs) Enable Pin. Drive EN pin low to turn on the device, drive it high to turn it off. Floating is default low. Supply Voltage Input Pin. XL4001 operates from a 4.5V to 40V DC voltage. Bypass Vin to GND with a suitably large capacitor to eliminate noise on the input. Rev 1.2 www.xlsemi.com 2 Datasheet 2A 150kHz 40V Buck DC/DC Converter With Constant Current Loop XL4001 Function Block Figure3. Function Block Diagram of XL4001 Typical Application Circuit (Car Charger) Figure4. XL4001 Typical Application Circuit (Li Battery Charger) Rev 1.2 www.xlsemi.com 3 Datasheet 2A 150kHz 40V Buck DC/DC Converter With Constant Current Loop XL4001 Typical Application Circuit (Buck LED Constant Current Driver) L 33uh EN FB VIN +6V~36V 4 6 7,8 XL4001 1,2 SW 3 5 CS GND VOUT CIN C1 100uf/50V 105 LED 1W~5W R2 D1 1N5821 COUT 100uf/35V R1 1K Rcs Figure5. XL4001 Typical Application Circuit (LED Constant Current Driver) Ordering Information Package Temperature Range Part Number Lead Free XL4001E1 XL4001TRE1 Marking ID Lead Free XL4001E1 XL4001E1 Packing Type Tube Tape & Reel XLSEMI Pb-free products, as designated with “E1” suffix in the par number, are RoHS compliant. Absolute Maximum Ratings（Note1） Parameter Symbol Value -0.3 to 45 -0.3 to Vin -0.3 to Vin -0.3 to Vin Internally limited Unit V V V V mW Input Voltage Vin FB Pin Voltage VFB EN Pin Voltage VEN SW Pin Voltage VSW Power Dissipation PD Thermal Resistance 60 ºC/W RJA (Junction to Ambient, No Heatsink, Free Air) Operating Junction Temperature -40 to 125 ºC TJ Storage Temperature -65 to 150 ºC TSTG Lead Temperature (Soldering, 10 sec) 260 ºC TLEAD ESD (HBM) 2000 V Note1: Stresses greater than those listed under Maximum Ratings may cause permanent damage to the device. This is a stress rating only and functional operation of the device at these or any other conditions above those indicated in the operation is not implied. Exposure to absolute maximum rating conditions for extended periods may affect reliability. Rev 1.2 www.xlsemi.com 4 Datasheet 2A 150kHz 40V Buck DC/DC Converter With Constant Current Loop XL4001 XL4001 Electrical Characteristics Ta = 25℃;unless otherwise specified. Symbol Parameter Test Condition Min. Typ. Max. Unit 1.21 1.235 1.26 V - 83 - % System parameters test circuit figure4 Feedback Voltage VFB ŋ Efficiency Vin = 8V to 32V, Vout=5V Iload=0.2A to 2A Vin=12V ,Vout=5V Iout=2A Electrical Characteristics (DC Parameters) Vin = 12V, GND=0V, Vin & GND parallel connect a 220uf/50V capacitor; Iout=500mA, Ta = 25℃; the others floating unless otherwise specified. Parameters Symbol Test Condition Min. Typ. 4.5 Max. Unit 40 V Input operation voltage Vin Shutdown Supply Current ISTBY VEN=5V 80 200 uA Quiescent Supply Current Iq VEN =0V, VFB =Vin 2 5 mA 150 172 Khz Oscillator Frequency Fosc Switch Current Limit IL VFB =0 3 A EN Pin Threshold VEN High (Regulator OFF) Low (Regulator ON) 1.4 0.8 V Output Saturation Voltage VCE VFB=0V ISW=2A 1.1 Constant Voltage VCS current sense 127 1.4 0.140 0.155 0.170 Rev 1.2 V V www.xlsemi.com 5 Datasheet 2A 150kHz 40V Buck DC/DC Converter With Constant Current Loop XL4001 Schottky Diode Selection Table Current 1A 3A Surface Through VR (The same as system maximum input voltage) Mount Hole 20V 30V 40V 50V 1N5817 1N5818 1N5819 √ 60V √ 1N5820 1N5821 1N5822 √ MBR320 MBR330 MBR340 MBR350 MBR360 SK32 SK33 SK34 SK36 30WQ03 30WQ04 30WQ05 31DQ03 31DQ04 31DQ05 SR303 SR304 SR305 √ √ √ √ SR302 Rev 1.2 SK35 SR306 www.xlsemi.com 6 Datasheet 2A 150kHz 40V Buck DC/DC Converter With Constant Current Loop XL4001 Package Information (SOP8-EP) Rev 1.2 www.xlsemi.com 7