LTC4100 - Smart Battery Charger Controller

1 LTC 410014100fcFor more information applicaTionDescripTionSmart BatteryCharger ControllerThe LT C 4100 Smart Battery Charger is a single chip charging solution that dramatically simplifies construction of an SBS compliant system. The LTC4100 implements a Level 2 Charger function whereby the Charger can be programmed by the Battery or by the host. A SafetySignal on the Battery being charged is monitored for temperature, connectivity and Battery type information. The SMBus interface remains alive when the AC power adapter is removed and responds to all SMBus activity directed to it, including SafetySignal status (via the ChargerStatus command).

2 The Charger also provides an interrupt to the host whenever a status change is detected ( , Battery removal, AC adapter connection).Charging current and voltage are restricted to chemistry-specific limits for improved system safety and reliability. Limits are programmable by two external resistors. Ad-ditionally, the maximum average current from the AC adapter is programmable to avoid overloading the adapter when simultaneously supplying load current and charging current. When supplying system load current, charg-ing current is automatically reduced to prevent adapter 1.

3 4A Smart Battery Charger FeaTuresapplicaTionsn Single Chip Smart Battery Charger Controllern 100% Compliant (Rev. ) SMBus Support Allows for Operation with or without Hostn SMBus Accelerator Improves SMBus Timingn Wide Output Voltage Range: to 26Vn Hardware Interrupt and SMBA lert Response Eliminate Interrupt Pollingn High Efficiency Synchronous Buck Chargern Dropout Voltage; Maximum Duty Cycle > 98%n AC Adapter Current Limit Maximizes Charge Raten Voltage Accuracy; 4% Current Accuracyn Up to 4A Charging Current Capabilityn 10-Bit DAC for Charge Current Programmingn 11-Bit DAC for Charger Voltage Programmingn User-Selectable Overvoltage and Overcurrent Limitsn High Noise Immunity SafetySignal Sensorn Available in a 24-Pin SSOP Packagen Portable Instruments and Computersn Data Storage Systems and Battery Backup ServersL, LT, LT C, LT M.

4 Linear Technology and the Linear logo are registered trademarks and PowerPath is a trademark of Linear Technology Corporation. All other trademarks are the property of their respective owners. Protected by Patents including 6650174 and TO 20 F20 F10 SMBCLK5kSMBDATSMBCLKSMBDATDCIN4100 TA01 CHGENSMBALERT#ACPSMART BATTERYSYSTEM < > 410024100fcFor more information conFiguraTionabsoluTe MaxiMuM raTingsVoltage from VDD to GND ..7V/ from CHGEN, DCDIV, SDA, SCL and SMBALERT to GND.

5 7V/ from DCIN, CLP, CLN to GND ..32V/ from CLP to CLN .. wrt. GND .. , BAT to GND ..28V/ 5 VOperating Ambient Temper atur e Range (Note 4) 40 C to 85 CJunction Temper atur e Range .. 40 C to 125 CStorage Temper atur e Range .. 65 C to 150 CLead Temper atur e (Soldering, 10 sec) ..300 C(Note 1)123456789101112 TOP VIEWG PACKAGE24-LEAD PLASTIC SSOP242322212019181716151413 TGATEPGNDBGATEINFETDCINCHGENSMBALERTSDAS CLACPDCDIVGNDCLPCLNBATCSPIDCITHVSETVDDTH ATHBVLIMILIM TJMAX = 125 C, JA = 90 C/WorDer inForMaTionLEAD FREE FINISHTAPE AND REELPART MARKINGPACKAGE DESCRIPTIONTEMPERATURE RANGELTC4100EG#PBFLTC4100EG#TRPBFLTC4100 EG24-Lead Plastic SSOP 40 C to 85 CLEAD BASED FINISHTAPE AND REELPART MARKINGPACKAGE DESCRIPTIONTEMPERATURE RANGELTC4100 EGLTC4100EG#TRLTC4100EG24-Lead Plastic SSOP 40 C to 85 CConsult LT C Marketing for parts specified with wider operating temperature more information on lead free part marking, go to.

6 For more information on tape and reel specifications, go to: Operating Range 628 VIDCINDCIN Operating CurrentCharging, Sum of Currents on DCIN, CLP and CLN35mAVTOLC harge Voltage Accuracy(Note 2) 1% %ITOLC harge Current Accuracy (Note 3)VCSP VBAT Target = IDAC = 0xFFFF 4 5 4 5% %VDDVDD Operating Voltage0V VDCIN 28V Leakage CurrentDCIN = 0V, VCLP = VCLN = VCSP = VBAT 1535 AUVLOU ndervoltage Lockout ThresholdDCIN Rising, VBAT = 0V Power-FailPart Held in Reset Until this VDD Present 3 VDCIN Current in ShutdownVCHGEN = 0V23mAelecTrical characTerisTics The l denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25 C.

7 VDCIN = 20V, VDD = , VB AT = 12V unless otherwise noted. (Note 4)LTC 410034100fcFor more information characTerisTics The l denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25 C. VDCIN = 20V, VDD = , VB AT = 12V unless otherwise noted. (Note 4)SYMBOLPARAMETERCONDITIONSMINTYPMAXUNIT SC urrent Sense Amplifier, CA1 Input Bias Current into BAT ACMSLCA1/I1 Input Common Mode Low 0 VCMSHCA1/I1 Input Common Mode HighVDCIN 28V VCLN Comparators ICMP and IREVITMAXM aximum Current Sense Threshold (VCSP VBAT) VITH = 140165200mVITREVR everse Current Threshold (VCSP VBAT)

8 30mVCurrent Sense Amplifier, CA2 Transconductance1mmhoSource CurrentMeasured at ITH, VITH = 40 ASink CurrentMeasured at ITH, VITH = ACurrent Limit Limit Threshold 93100107mVICLNCLN Input Bias Current100nAVoltage Error Amplifier, EATransconductance1mmhoSink Current Measured at ITH, VITH = AOVSDO vervoltage Shutdown Threshold as a Percent of Programmed Charger Voltage 102107110%Input P-Channel FET Driver (INFET)DCIN Detection Threshold (VDCIN VCLP)DCIN Voltage Ramping Up from VCLP Regulation Voltage (VDCIN VCLP) 2550mVReverse Voltage Turn-Off Voltage (VDCIN VCLP) 60 25mVINFET ON Clamping Voltage (VDCIN VINFET)IINFET = 1 A OFF Clamping Voltage (VDCIN VINFET)IINFET = 25 Switching Frequency255300345kHzfMINR egulator Switching Frequency in Drop OutDuty Cycle 98%2025kHzDCMAX Regulator Maximum Duty CycleVCSP = VBAT9899%Gate Drivers (TGATE, BGATE)VTGATE High (VCLP-VTGATE)ITGATE = 1mA50mVVBGATE HighCLOAD = Low (VCLP-VTGATE)

9 CLOAD = LowIBGATE = 1mA50mV TGTR TGTFTGATE Transition Time TGATE Rise Time TGATE Fall Time CLOAD = 3000pF, 10% to 90% CLOAD = 3000pF, 10% to 90% 50 50 110 100 ns ns BGTR BGTFBGATE Transition Time BGATE Rise Time BGATE Fall Time CLOAD = 3000pF, 10% to 90% CLOAD = 3000pF, 10% to 90% 40 40 90 80 ns nsVTGATE at Shutdown (VCLN-VTGATE)ITGATE = 1 A100mVVBGATE at ShutdownITGATE = 1 A100 mVLTC 410044100fcFor more information characTerisTics The l denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25 C.

10 VDCIN = 20V, VDD = , VB AT = 12V unless otherwise noted. (Note 4)SYMBOLPARAMETERCONDITIONSMINTYPMAXUNIT SAC Present ComparatorVACPDCDIV ThresholdVDCDIV Rising from 1V to Hysteresis25mVDCDIV Input Bias CurrentVDCDIV = 11 AACP VOHIACP = 2mA2 VACP VOLIACP = to ACP DelayVDCDIV = sSafetySignal DecoderSafetySignal Trip (RES_COLD/RES_OR)RTHA = 1130 1%, CTH = 1nF (Note 6) RTHB = 1% 95100105k SafetySignal Trip (RES_IDEAL/RES_COLD)RTHA = 1130 1%, CTH = 1nF (Note 6) RTHB = 1% SafetySignal Trip (RES_HOT/RES_IDEAL)