Datasheet LTC1760 (Analog Devices)

LTC1760 Dual Smart Battery System Manager
FEATURES DESCRIPTION
n
SMBus Charger/Selector for Two Smart Batteries*
The LTC®1760 Smart Battery System Manager is a highly- n
Voltage and Current Accuracy within 0.2% of Value
integrated SMBus Level 3 battery charger and selector
Reported by Battery
intended for products using dual smart batteries. Three n
Simplifies Construction of “Smart Battery System
SMBus interfaces allow the LTC1760 to servo to the internal voltage and currents measured by the batteries
Manager”
n while allowing an SMBus Host device to monitor either
Includes All SMBus Charger V1.1 Safety Features
n battery’s status. Charging accuracy is determined by the
Supports Autonomous Operation without a Host
battery’s internal voltage and current measurements, n
Allows Both Batteries to Discharge Simultaneously
typically better than ±0.2%.
into Single Load with Low Loss (Ideal Diode)
n SMBus Switching for Dual Batteries with Alarm A proprietary PowerPath architecture supports simultane- Monitoring for Charging Battery at All Times ous charging or discharging of both batteries. Typical battery n run times are extended by up to 10%, while charging times Pin Programmable Limits for Maximum Charge are reduced by up to 50%. The LTC1760 automatically Current and Voltage Improve Safety n switches between power sources in less than 10µs to prevent Fast Autonomous PowerPath™ Switching (<10µs) n power interruption upon battery or wall adapter removal. Low Loss Simultaneous Charging of Two Batteries n >95% Efficient Synchronous Buck Charger The LTC1760 implements all elements of a version 1.1 n AC Adapter Current Limiting* Maximizes Charge Rate “Smart Battery System Manager” except for the generation n SMBus Accelerator Improves SMBus Timing** of composite battery information. An internal multiplexer n cleanly switches the SMBus Host to either of the two Available in 48-Lead TSSOP Package attached Smart Batteries without generating partial mes- sages to batteries or SMBus Host. Thermistors on both
APPLICATIONS
batteries are automatically monitored for temperature and n Portable Computers and Instruments disconnection information (SafetySignal). n Standalone Dual Smart Battery Chargers L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and n Battery Backup Systems PowerPath is a trademark of Analog Devices, Inc. All other trademarks are the property of their respective owners. Protected by U.S. Patents including *5723970 **6650174.
TYPICAL APPLICATION Dual Battery Charger/Selector System Architecture Dual vs Sequential Charging
DC 3500 IN 3000 BAT1 BAT2 2500 CURRENT CURRENT 2000
SEQUENTIAL
SYSTEM 1500 POWER 1000 500 0 LTC1760 3500 3000 BAT1 SMBus (HOST) 2500 CURRENT BAT2 BATTERY CURRENT (mA) 2000 CURRENT
DUAL
1500 1000 100 SafetySignal 1 500 0 MINUTES SMBus 1 0 50 100 150 200 250 300 TIME (MINUTES) BATTERY TYPE: 10.8V Li-Ion (MOLTECH NI2020) SafetySignal 2 REQUESTED CURRENT = 3A REQUESTED VOLTAGE = 12.3V SMBus 2 MAX CHARGER CURRENT = 4.1A 1760 TA03 1760 TA01 1760fc For more information www.linear.com/LTC1760 1