POWER LOSS (mW) LTC4012/ LTC4012-1/LTC4012-2 High Efficiency, Multi-Chemistry Battery Charger with PowerPath Control Fserutae Dnoitpircse n General Purpose Battery Charger Controller The LTC4012 is a constant-current/constant-volt- n Efficient 550kHz Synchronous Buck PWM Topology age battery charger controller. It uses a synchronous n 0.5% Output Float Voltage Accuracy quasi-constant frequency PWM control architecture n Programmable Charge Current: 4% Accuracy that will not generate audible noise with ceramic bulk n Programmable AC Adapter Current Limit: capacitors. Charge current is set by external resis- 3% Accuracy tors and can be monitored as an output voltage. n No Audible Noise with Ceramic Capacitors With no built-in termination, the LTC4012 family charges n INFET Low Loss Ideal Diode PowerPath Control a wide range of batteries under external control. n Wide Input Voltage Range: 6V to 28V The LTC4012 features fully adjustable output voltage, while n Wide Output Voltage Range: 2V to 28V the LTC4012-1 and LTC4012-2 can be pin-programmed for n Indicator Outputs for AC Adapter Present, Charging, Lithium-Ion/Polymer battery packs of 1-, 2-, 3- or 4-series C/10 Current Detection and Input Current Limiting cells. The LTC4012-1 provides output voltage of 4.1V/cell n Analog Charge Current Monitor and the LTC4012-2 is a 4.2V/cell version. n Micropower Shutdown n The device includes AC adapter input current limiting, which 20-Pin 4mm 4mm 0.75mm QFN Package maximizes charge rate for a fixed input power level. An external sense resistor programs the input current limit, a snoitacilpp and the ICL status pin indicates reduced charge current as n Notebook Computers a result of AC adapter current limiting. Ideal diode control n Portable Instruments at the adaptor input improves charger efficiency. n Battery Backup Systems The CHRG status pin is active during all charging modes, L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and including special indication for low charge current. PowerPath and ThinSOT are trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. Protected by U.S. Patents including 5723970. t lacipy a noitacilpp FROM 25m Efficiency at DCIN = 20V POWER TO ADAPTER SYSTEM 0.1F 13V TO 28V 20F 100 10000 5.1k INFET CLP EFFICIENCY 95 CLN DCIN BOOST 0.1F 90 0.1F TGATE ACP 85 POWER LOSS 1000 SW CHRG INTV DD TO/FROM 2F 80 MCU ICL BGATE 6.8H V = 12.3V OUT R = 33m SENSE SHDN GND 75 R = 3.01k IN 3.01k R = 26.7k PROG ITH CSP 70 100 6.04k 0 0.5 1 1.5 2 2.5 3 LTC4012 33m 3.01k CHARGE CURRENT (A) 0.1F CSN BAT PIN NAME PROG FBDIV 20F PART INFET DCDIV 301k + LTC4009 X 26.7k 4.7nF 12.3V V LTC4012 X FB 4012 TA02 Li-Ion 32.8k BATTERY 4012 TA01 4012fa EFFICIENCY (%)LTC4012/ LTC4012-1/LTC4012-2 a etulosbMixa Mu M r sgnita (Note 1) DCIN ............................................................14V to 30V SHDN, FVS0, FVS1 or V to GND ...............0.3V to 7V FB DCIN to CLP ................................................ 32V to 20V ACP, CHRG or ICL to GND .......................... 0.3V to 30V CLP, CLN or SW to GND ............................. 0.3V to 30V Operating Temperature Range CLP to CLN ............................................................0.3V (Note 2) ............................................. 40C to 125C CSP, CSN or BAT to GND ........................... 0.3V to 28V Junction Temperature (Note 3) ............................. 125C CSP to CSN ............................................................0.3V Storage Temperature Range ..................65C to 150C BOOST to GND ........................................... 0.3V to 36V BOOST to SW...............................................0.3V to 7V p ni c no Fnoitarugi LTC4012 LTC4012-1 LTC4012-2 TOP VIEW TOP VIEW 20 19 18 17 16 20 19 18 17 16 CLN 1 15 CSP CLN 1 15 CSP CLP CSN CLP CSN 2 14 2 14 21 21 INFET 3 13 PROG INFET 3 13 PROG GND GND DCIN 4 12 ITH DCIN 4 12 ITH ACP 5 11 BAT ACP 5 11 BAT 6 7 8 9 10 6 7 8 9 10 UF PACKAGE UF PACKAGE 20-LEAD (4mm s 4mm) PLASTIC QFN 20-LEAD (4mm s 4mm) PLASTIC QFN T = 125C, = 37C/W T = 125C, = 37C/W JMAX JA JMAX JA EXPOSED PAD (PIN 21) IS GND, MUST BE SOLDERED TO PCB EXPOSED PAD (PIN 21) IS GND, MUST BE SOLDERED TO PCB o r D re i n Fro Mnoita LEAD FREE FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE LTC4012CUF PBF LTC4012CUF TRPBF 4012 20-Lead (4mm 4mm) Plastic QFN 0C to 85C LTC4012CUF-1 PBF LTC4012CUF-1 TRPBF 40121 20-Lead (4mm 4mm) Plastic QFN 0C to 85C LTC4012CUF-2 PBF LTC4012CUF-2 TRPBF 40122 20-Lead (4mm 4mm) Plastic QFN 0C to 85C LTC4012IUF PBF LTC4012IUF TRPBF 4012 40C to 125C 20-Lead (4mm 4mm) Plastic QFN LTC4012IUF-1 PBF LTC4012IUF-1 TRPBF 40121 40C to 125C 20-Lead (4mm 4mm) Plastic QFN LTC4012IUF-2 PBF LTC4012IUF-2 TRPBF 40122 20-Lead (4mm 4mm) Plastic QFN 40C to 125C Consult LTC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container. Consult LTC Marketing for information on non-standard lead based finish parts. For more information on lead free part marking, go to: