LTC6802-1 Datasheet, PDF (1/32 Pages) Linear Technology – Multicell Battery Stack Monitor

FEATURES
n _{Measures up to 12 Li-Ion Cells in Series (60V Max)}
n _{Stackable Architecture Enables >1000V Systems}
n _{0.25% Maximum Total Measurement Error}
n _{13ms to Measure All Cells in a System}
n _{Cell Balancing:}
On-Chip Passive Cell Balancing Switches
Provision for Off-Chip Passive Balancing
n _{Two Thermistor Inputs Plus On-board}
Temperature Sensor
n _{1MHz Serial Interface with Packet Error Checking}
n _{High EMI Immunity}
n _{Delta Sigma Converter With Built In Noise Filter}
n _{Open Wire Connection Fault Detection}
n _{Low Power Modes}
n _{44-Lead SSOP Package}
APPLICATIONS
n _{Electric and Hybrid Electric Vehicles}
n _{High Power Portable Equipment}
n _{Backup Battery Systems}
n _{High Voltage Data Acquisition Systems}
Electrical Specifications Subject to Change
LTC6802-1
Multicell
Battery Stack Monitor
DESCRIPTION
The LTC^®6802-1 is a complete battery monitoring IC that
includes a 12-bit ADC, a precision voltage reference, a
high voltage input multiplexer and a serial interface. Each
LTC6802-1 can measure up to 12 series connected battery
cells with an input common mode voltage up to 60V. Using
a unique level-shifting serial interface, multiple LTC6802-1
devices can be connected in series, without optocouplers
or isolators, allowing for monitoring of every cell in a long
string of series-connected batteries.
When multiple LTC6802-1 devices are connected in series
they can operate simultaneously, permitting all cell voltages
in the stack to be measured within 13ms.
To minimize power, the LTC6802-1 offers a measure mode
to monitor each cell for overvoltage and undervoltage
conditions. A standby mode is also provided.
Each cell input has an associated MOSFET switch for
discharging overcharged cells.
The related LTC6802-2 offers an individually addressable
serial interface.
L, LT, LTC and LTM are registered trademarks of Linear Technology Corporation. All other
trademarks are the property of their respective owners.
TYPICAL APPLICATION
NEXT 12-CELL
PACK ABOVE
Typical Application
V⁺
LTC6802-1
SERIAL DATA
TO LTC6802-1
DIE TEMP
ABOVE
12-CELL
BATTERY
STRING
REGISTERS
AND
CONTROL
MUX
12-BIT
Δ∑ ADC
NEXT 12-CELL
PACK BELOW
V^–
100k NTC
EXTERNAL
TEMP
10ppm VOLTAGE
REFERENCE
SERIAL DATA
TO LTC6802-1
BELOW
68021 TA01a
100k
Measurement Error Over
Extended Temperature
0.30
0.25
0.20
0.15
0.10
0.05
0
–0.05
–0.10
–0.15
–0.20
–0.25
–0.30
–50 –25
0 25 50 75 100 125
TEMPERATURE (°C)
68021p
1