LTC4100 Smart Battery Charger Controller FeaTuresDescripTion n Single Chip Smart Battery Charger Controller The LTC®4100 Smart Battery Charger is a single chip n 100% Compliant (Rev. 1.1) SMBus Support Allows charging solution that dramatically simplifies construction for Operation with or without Host of an SBS compliant system. The LTC4100 implements n SMBus Accelerator Improves SMBus Timing a Level 2 charger function whereby the charger can be n Wide Output Voltage Range: 3.5V to 26V programmed by the battery or by the host. A SafetySignal n Hardware Interrupt and SMBAlert Response on the battery being charged is monitored for temperature, Eliminate Interrupt Polling connectivity and battery type information. The SMBus n High Efficiency Synchronous Buck Charger interface remains alive when the AC power adapter is n 0.5V Dropout Voltage; Maximum Duty Cycle > 98% removed and responds to all SMBus activity directed to n AC Adapter Current Limit Maximizes Charge Rate it, including SafetySignal status (via the ChargerStatus n ±0.8% Voltage Accuracy; ±4% Current Accuracy command). The charger also provides an interrupt to the n Up to 4A Charging Current Capability host whenever a status change is detected (e.g., battery n 10-Bit DAC for Charge Current Programming removal, AC adapter connection). n 11-Bit DAC for Charger Voltage Programming Charging current and voltage are restricted to chemistry- n User-Selectable Overvoltage and Overcurrent Limits specific limits for improved system safety and reliability. n High Noise Immunity SafetySignal Sensor Limits are programmable by two external resistors. Ad- n Available in a 24-Pin SSOP Package ditionally, the maximum average current from the AC adapter is programmable to avoid overloading the adapter applicaTions when simultaneously supplying load current and charging n Portable Instruments and Computers current. When supplying system load current, charg- n Data Storage Systems and Battery Backup Servers ing current is automatically reduced to prevent adapter L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and overload. PowerPath is a trademark of Linear Technology Corporation. All other trademarks are the property of their respective owners. Protected by U.S. Patents including 6650174 and 5723970. Typical applicaTion DCIN 0.1µF 13.7k VBAT PART 3V 1.21k < 5.5V LTC4101 TO 5.5V 0.1µF > 5.5V LTC4100 0.033Ω 17 LTC4100 5 VDD DCIN 11 4 DCDIV INFET 5k 6 24 SYSTEM LOAD CHGEN CHGEN CLP 10 23 ACP ACP CLN 20µF SMART BATTERY 7 1 0.025Ω SMBALERT TGATE 9 3 10µH SCL BGATE 8 2 SDA PGND 20µF 15 21 THB CSP 16 22 THA BAT 13 18 ILIM VSET 1.13k 14 19 100Ω VLIM ITH 0.01µF 20 12 10k IDC GND 6.04k 54.9k 0.0015µF 0.068µF 0.12µF 0.1µF SMBALERT# SafetySignal SMBCLK SMBCLK SMBDAT SMBDAT 4100 TA01 Figure 1. 4A Smart Battery Charger 4100fc For more information www.linear.com/LTC4100 1
