datasheet 5a 180khz 36v buck dc to dc converter xl4015 rev 1.3 www.xlsemi.com 1 features n wide 8v to 36v input voltage range n output adjustable from 1.25v to 32v n maximum duty cycle 100% n minimum drop out 0.3v n fixed 180khz switching frequency n 5a constant output current capability n internal optimize power mosfet n high efficiency up to 96% n excellent line and load regulation n built in thermal shutdown function n built in current limit function n built in output short protection function n available in to263-5l package applications n lcd monitor and lcd tv n portable instrument power supply n telecom / networking equipment general description the xl4015 is a 180 khz fixed frequency pwm buck (step-down) dc/dc converter, capable of driving a 5a 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. the pwm control circuit is able to adjust the duty ratio linearly from 0 to 100%. an over current protection function is built inside. when short protection function happens, the operation frequency will be reduced from 180khz to 48khz. an internal compensation block is built in to minimize external component count. figure1. package type of xl4015
datasheet 5a 180khz 36v buck dc to dc converter xl4015 rev 1.3 www.xlsemi.com 2 pin configurations figure2. pin configuration of xl4015 (top view) table 1 pin description pin number pin name description 1 gnd ground pin. care must be taken in layout. this pin should be placed outside of the schottky diode to output capacitor ground path to prevent switching current spikes from inducing voltage noise into xl4015. 2 fb feedback pin (fb). through an external resistor divider network, fb senses the output voltage and regulates it. the feedback threshold voltage is 1.25v. 3 sw power switch output pin (sw). sw is the switch node that supplies power to the output. 4 vc internal voltage regulator bypass capacity. in typical system application, the vc pin connect a 1uf capacity to vin. 5 vin supply voltage input pin. xl4015 operates from a 8v to 36v dc voltage. bypass vin to gnd with a suitably large capacitor to eliminate noise on the input.
datasheet 5a 180khz 36v buck dc to dc converter xl4015 rev 1.3 www.xlsemi.com 3 function block figure3. function block diagram of xl4015 typical application circuit figure4. xl4015 typical application circuit (vin=8v~36v, vout=5v/5a)
datasheet 5a 180khz 36v buck dc to dc converter xl4015 rev 1.3 www.xlsemi.com 4 ordering information order information marking id package type packing type supplied as XL4015E1 XL4015E1 to263-5l 800 units on 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 unit input voltage vin -0.3 to 40 v feedback pin voltage v fb -0.3 to vin v output switch pin voltage v output -0.3 to vin v power dissipation p d internally limited mw thermal resistance (to263-5l) (junction to ambient, no heatsink, free air) r ja 30 o c/w operating junction temperature t j -40 to 125 o c storage temperature t stg -65 to 150 o c lead temperature (soldering, 10 sec) t lead 260 o c 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.
datasheet 5a 180khz 36v buck dc to dc converter xl4015 rev 1.3 www.xlsemi.com 5 xl4015 electrical characteristics t a = 25 ;unless otherwise specified. symbol parameter test condition min. typ. max. unit system parameters test circuit figure4 vfb feedback voltage vin = 8v to 40v, vout=5v iload=0.5a to 5a 1.225 1.25 1.275 v efficiency ? vin=12v ,vout=5v iout=5a - 87 - % efficiency ? vin=24v ,vout=12v iout=4a - 93 - % electrical characteristics (dc parameters) vin = 12v, gnd=0v, vin & gnd parallel connect a 220uf/50v capacitor; iout=500ma, t a = 25 ; the others floating unless otherwise specified. parameters symbol test condition min. typ. max. unit input operation voltage vin 8 36 v quiescent supply current i q v fb =vin 2.1 5 ma oscillator frequency fosc 144 180 216 khz output short frequency fosp 48 khz switch current limit i l v fb =0 7 a max. duty cycle d max v fb =0v 100 % output power pmos rdson v fb =0v, vin=12v, i sw =5a 60 80 mohm
datasheet 5a 180khz 36v buck dc to dc converter xl4015 rev 1.3 www.xlsemi.com 6 typical system application (vout=5v/5a) figure5. xl4015 system parameters test circuit (vin=8v~36v, vout=5v/5a) 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 50 55 60 65 70 75 80 85 90 95 100 efficiency vs output current efficiency(%) load current(a) vin=8v,vout=5v,iout=0.1a~5a vin=12v,vout=5v,iout=0.1a~5a vin=24v,vout=5v,iout=0.1a~5a vin=36v,vout=5v,iout=0.1a~5a figure6. xl4015 system efficiency curve
datasheet 5a 180khz 36v buck dc to dc converter xl4015 rev 1.3 www.xlsemi.com 7 typical system application (vout=12v/4a) figure7. xl4015 system parameters test circuit (vin=15v~36v, vout=12v/4a) 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 50 55 60 65 70 75 80 85 90 95 100 efficiency vs output current efficiency(%) output current(a) vin=15v,vout=12v,iout=0.1a~4a vin=24v,vout=12v,iout=0.1a~4a vin=36v,vout=12v,iout=0.1a~4a figure8. xl4015 system efficiency curve
datasheet 5a 180khz 36v buck dc to dc converter xl4015 rev 1.3 www.xlsemi.com 8 typical system application (ttl shutdown function) logic level signals shutdown function can be used in typical system application with external components. when the ttl high voltage above 3.3v(referenced to ground, lower than vin), the converter will shutdown, input current less than 5ma; when the ttl low voltage below 0.8v(referenced to ground), the converter will turn on. xl4015 cin 220uf/50v cout 330uf/25v r2 10k r1 3.3k l1 47uh/5a d1 b540 c1 105 c2 105 5 3 1 2 vin 4 vout=1.25*(1+r2/r1) vin vc sw gnd fb cc 105 r3 10k d2 1n4148 off(high>3.3v) on(low<0.8v) ttl current capability larger than ttl high voltage/(r1+r3) figure9. xl4015 typical application circuit
datasheet 5a 180khz 36v buck dc to dc converter xl4015 rev 1.3 www.xlsemi.com 9 schottky diode selection table current surface mount through hole vr (the same as system maximum input voltage) 20v 30v 40v 50v 60v 1a 1n5817 1n5818 1n5819 1n5820 1n5821 1n5822 mbr320 mbr330 mbr340 mbr350 mbr360 sk32 sk33 sk34 sk35 sk36 30wq03 30wq04 30wq05 31dq03 31dq04 31dq05 3a sr302 sr303 sr304 sr305 sr306 1n5823 1n5824 1n5825 sr502 sr503 sr504 sr505 sr506 sb520 sb530 sb540 sb550 sb560 sk52 sk53 sk54 sk55 sk56 5a 50wq03 50wq04 50wq05
datasheet 5a 180khz 36v buck dc to dc converter xl4015 rev 1.3 www.xlsemi.com 10 package information to263-5l
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