LTC6801
1
6801fc
For more information www.linear.com/LTC6801
APPLICATIONS
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Redundant Battery Monitor
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Hybrid Electric Vehicles
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Battery Backup Systems
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Power Systems Using Multiple Battery Cells
L, LT, LT C , LT M, Linear Technology and the Linear logo are registered trademarks of Linear
Technology Corporation. All other trademarks are the property of their respective owners.
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Monitors Up to 12 Li-Ion Cells in Series (60V Max)
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Stackable Architecture Enables > 1000V Systems
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1% Maximum Overvoltage Detection Level Error
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Adjustable Overvoltage and Undervoltage Detection
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Self Test Features Guarantee Accuracy
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Robust Fault Detection Using Differential Signals
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Simple Pin-Strapped Configuration Allows Battery
Monitoring without a Microcontroller
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15.5ms to Monitor All Cells in a System
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Programmable Response Time
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Two Temperature Monitor Inputs
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Low Power Idle Mode
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36-Lead SSOP Package
–40 20 95–10 50 110
5 80–25 35 65
TEMPERATURE (°C)
–0.8
0.8
0.4
0
–0.4
0.6
0.2
–0.2
–0.6
–1.0
V
+
= 43.2V
OV = 4.116V
5 TYPICAL UNITS
BLOCK DIAGRAM
DESCRIPTION
Independent Multicell
Battery Stack Fault Monitor
The LTC
®
6801 is a multicell battery monitoring IC in-
corporating a 12-bit ADC, a precision voltage reference,
sampled comparator, and a high voltage input multiplexer.
The LTC6801 can monitor as many as 12 series con-
nected battery cells for overvoltage, undervoltage, and
overtemperature conditions, indicating whether the cells
are within specified parameters. The LTC6801 generates
a clock output when no fault conditions exist. Differential
clocking provides high noise immunity and ensures that
battery stack fault conditions cannot be hidden by frozen
bits or short circuit conditions.
Each LTC6801 can operate with a battery stack voltage up
to 60V and multiple LTC6801 devices can be stacked to
monitor each individual cell in a long battery string. When
multiple devices are stacked, the status signal of each
LTC6801 can be daisy-chained, without opto-couplers or
isolators, providing a single status output for the entire
battery string.
The LTC6801 is configurable by external pin strapping.
Adjustable overvoltage and undervoltage thresholds sup-
port various Li-Ion chemistries. Selectable measurement
times allow users to save power.
FEATURES
6801 TA01a
1
2
3
12
13
20
22
14
15 16
V
REF
V
TEMP1
V
TEMP2
NTC
NTC
C1
C2
C11
C12
V
+
V
–
NEXT LOWER
CELL PACK
CELL PACK
12
MUX
“CELLS GOOD”
ENABLE
INPUT
ISOLATION
CLOCK SIGNAL
INPUT ENABLES
THE LTC6801
CLOCK SIGNAL
SYSTEM “OK”
STATUS
OUTPUT
CONTROL
LOGIC
17
REFERENCE
LTC6801
ADC
0V Detection Level Error