Kontron MARS Smart Battery Kit - Manual (Page 14)

MARS User´s Guide
5. Smart Battery System Manager
(Abbr.: SBS Manager)
The SBS Manager in the SBS MARS is realised by the LTC1760 from Linear Technologies.
This IC has following characteristics:
• SMBus Charger/Selector for Two Smart Batteries*
• Voltage and Current Accuracy within 0.2% of Value
Reported by Battery
• Includes All SMBus Charger V1.1 Safety Features
• Supports Autonomous Operation without a Host
• Allows Both Batteries to Discharge Simultaneously
into Single Load with Low Loss (Ideal Diode)
The LTC1760 Smart Battery System Manager is a highly integrated level 3 battery charger and
selector intended for products using dual smart batteries. Three SMBus interfaces allow the
LTC1760 to servo to the internal voltage and currents measured by the batteries while allowing an
SMBus Host to monitor either battery’s status. Charging accuracy is determined by the battery’s
internal voltage and current measurement, typically better than ±0.2%.
A proprietary PowerPath
TM architecture supports simultaneous charging or discharging of both
batteries. Typical battery run times are extended by up to 10%, while charging times are reduced
by up to 50%. The LTC1760 automatically switches between power sources in less than 10μs to
prevent power interruption upon battery or wall adapter removal.
The LTC1760 implements all elements of a version 1.1 “Smart Battery System Manager” except for
the generation of composite battery information. An internal multiplexer cleanly switches the
SMBus Host to either of the two attached Smart Batteries without generating partial messages to
batteries or SMBus Host. Thermistors on both batteries are automatically monitored for
temperature and disconnection information (SafetySignal).
Hardware programmable limits for maximum charge current and voltage improve the safety of the
complete system.
5.1 Possible Configurations
5.1.1 LOPWR TRIP
The threshold voltage controls the voltage which source the system. When the voltage of the active
source drops below this threshold, then the currently best voltage source is selected.
This Threshold voltage is configurable with the following jumper resistors (0Ω):
Smart Battery System Manager
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