POWER (W) LTC4020 55V Buck-Boost Multi-Chemistry Battery Charger Fea T Descrip T n Wide Voltage Range: 4.5V to 55V Input, Up to 55V The LTC 4020 is a high voltage power manager provid- Output (60V Absolute Maximums) ing PowerPath instant-on operation and high efficiency n Synchronous Buck-Boost DC/DC Controller battery charging over a wide voltage range. An onboard n Li-Ion and Lead-Acid Charge Algorithms buck-boost DC/DC controller operates with battery and/or n 0.5% Float Voltage Accuracy system voltages above, below, or equal to the input voltage. n 5% Charge Current Accuracy The LTC4020 seamlessly manages power distribution n Instant-On for Heavily Discharged Batteries between battery and converter outputs in response to load n Ideal Diode Controller Provides Low Loss variations, battery charge requirements and input power PowerPath When Input Power is Limited supply limitations. n Input Voltage Regulation for High Impedance Input The LTC4020 battery charger can provide a constant-current/ Supplies and Solar Panel Peak Power Operation n constant-voltage charge algorithm (CC/CV), constant- Onboard Timer for Protection and Termination n current charging (CC), or charging with an optimized 4-step, Bad Battery Detection with Auto-Reset n 3-stage lead-acid battery charge profile. Maximum converter NTC Input for Temperature Qualified Charging n and battery charge currents are resistor programmable. Binary Coded Open-Collector Status Pins n Low Profile (0.75mm) 38-Pin 5mm 7mm QFN The IC s instant-on operation ensures system load power Package even with a fully discharged battery. Additional safety features include preconditioning for heavily discharged a T batteries and an integrated timer for termination and n Portable Industrial and Medical Equipment protection. n Solar-Powered Systems L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and PowerPath is a trademark of Linear Technology Corporation. All other trademarks are the n Military Communications Equipment property of their respective owners. Protected by U.S. Patents, including 7583113 and 8405362. n 12V to 24V Embedded Automotive Systems Typical a T 5V to 30V 6-Cell Lead-Acid Supply/Charger Buck-Boost DC/DC Converter Controller with PowerPath Battery Charger Accepts Maximum Power Efficiency vs V IN Inputs from 4.5V to 55V and Produces Output Voltages Up to 55V (Application Circuit on Page 37) BUCK-BOOST R SENSEA DC/DC CONVERTER PowerPath BATTERY CHARGER 100 100 V V V = 14V OUT IN OUT 90 EFFICIENCY CSP 80 TG2 95 R CS LTC4020 70 CSN 60 90 BG2 INPUT POWER BGATE 50 VFB 85 40 R SENSEB 30 SENSGND 80 20 SENSBOT P(LOSS) 10 NTC BG1 75 0 R NTC 5 10 15 20 25 30 TG1 V (V) IN 4020 TA01b SENSTOP V SENSVIN FBMAX 4020 TA01a 4020fd 1 For more information www.linear.com/LTC4020 EFFICIENCY (%) ion pplica ions pplica ion uresLTC4020 a Te Maxi Mu M r a T p in c F T (Note 1) TOP VIEW PV , SENSVIN ............................................. 0.3 to 60V IN BST1, BST2 .................................................. 0.3 to 66V SW1, SW2 ........................................................2 to 60V 38 37 36 35 34 33 32 SENSVIN PV ........................................... 0.3 to 60V IN TG1 1 31 TG2 BST1 2 30 BST2 BST1 SW1, BST2 SW2 ............................. 0.3 to 6V SGND 3 29 SGND SENSVIN SENSTOP, SENSBOT SENSGND 4 28 VC SENSGND ....................................................0.3 to 0.3V SENSBOT 5 27 ITH CSP, CSN ..................................................... 0.3 to 60V 39 SENSTOP 6 26 V FBMAX SGND CSP CSN ...................................................0.3 to 0.3V SENSVIN 7 25 I LIMIT STAT1, STAT2, SHDN ................................... 0.3 to 60V RT 8 24 CSOUT SHDN 23 CSP 9 V , V , V , V , BAT, FBG ....... 0.3 to 60V FBMAX INREG FB FBMIN V 10 22 CSN IN REG MODE ............................................................. 0.3 to 6V MODE 11 21 BGATE Status Pin Currents: 20 STAT1 12 BAT STAT1, STAT2 ......................................................5mA 13 14 15 16 17 18 19 Operating Junction Temperature Range (Note 2) ....................................... 40C to 125C Storage Temperature Range .................. 65C to 150C UHF PACKAGE 38-LEAD PLASTIC QFN (5mm 7mm) T = 125C, = 34C/W, = 2C/W JMAX JA JC EXPOSED PAD (PIN 39) IS SGND, MUST BE SOLDERED TO PCB o r Der i n F Ma T (