Linear Technology LTC1760, Руководство пользователя

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LTC1760
1
1760fc
For more information www.linear.com/LTC1760
TYPICAL APPLICATION
FEATURES DESCRIPTION
Dual Smart Battery
System Manager
The LTC
®
1760 Smart Battery System Manager is a highly-
integrated SMBus 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 device to monitor either
battery’s status. Charging accuracy is determined by the
battery’s internal voltage and current measurements,
typically better than ±0.2%.
A proprietary PowerPath
architecture supports simultane-
ous 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 mes-
sages to batteries or SMBus Host. Thermistors on both
batteries are automatically monitored for temperature and
disconnection information (SafetySignal).
Dual vs Sequential Charging
APPLICATIONS
n
SMBus Charger/Selector for Two Smart Batteries*
n
Voltage and Current Accuracy within 0.2% of Value
Reported by Battery
n
Simplifies Construction of “Smart Battery System
Manager”
n
Includes All SMBus Charger V1.1 Safety Features
n
Supports Autonomous Operation without a Host
n
Allows Both Batteries to Discharge Simultaneously
into Single Load with Low Loss (Ideal Diode)
n
SMBus Switching for Dual Batteries with Alarm
Monitoring for Charging Battery at All Times
n
Pin Programmable Limits for Maximum Charge
Current and Voltage Improve Safety
n
Fast Autonomous PowerPath
™
Switching (<10µs)
n
Low Loss Simultaneous Charging of Two Batteries
n
>95% Efficient Synchronous Buck Charger
n
AC Adapter Current Limiting* Maximizes Charge Rate
n
SMBus Accelerator Improves SMBus Timing**
n
Available in 48-Lead TSSOP Package
n
Portable Computers and Instruments
n
Standalone Dual Smart Battery Chargers
n
Battery Backup Systems
LTC1760
DC
IN
SYSTEM
POWER
SMBus (HOST)
1760 TA01
SafetySignal 1
SMBus 1
SafetySignal 2
SMBus 2
TIME (MINUTES)
BATTERY CURRENT (mA)
3500
3000
2500
2000
1500
1000
500
0
3500
3000
2500
2000
1500
1000
500
0
1760 TA03
0
50
100 150 200 250 300
BAT1
CURRENT
BAT2
CURRENT
SEQUENTIAL
DUAL
BAT1
CURRENT
100
MINUTES
BATTERY TYPE: 10.8V Li-Ion (MOLTECH NI2020)
REQUESTED CURRENT = 3A
REQUESTED VOLTAGE = 12.3V
MAX CHARGER CURRENT = 4.1A
BAT2
CURRENT
Dual Battery Charger/Selector System Architecture
L
, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and
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.