LTC6813-1
Multicell Battery Monitor
FEATURES
n
n
n
n
DESCRIPTION
The
LTC
®
6813-1
is a multicell battery stack monitor that
measures up to 18 series connected battery cells with
a total measurement error of less than 2.2mV. The cell
measurement range of 0V to 5V makes the LTC6813-1
suitable for most battery chemistries. All 18 cells can be
measured in 290µs, and lower data acquisition rates can
be selected for high noise reduction.
Multiple LTC6813-1 devices can be connected in series,
permitting simultaneous cell monitoring of long, high
voltage battery strings. Each LTC6813-1 has an isoSPI
interface for high speed, RF immune, long distance com-
munications. Multiple devices are connected in a daisy
chain with one host processor connection for all devices.
This daisy chain can be operated bidirectionally, ensuring
communication integrity, even in the event of a fault along
the communication path.
The LTC6813-1 can be powered directly from the battery
stack or from an isolated supply. The LTC6813-1 includes
passive balancing for each cell, with individual PWM duty
cycle control for each cell. Other features include an on-
board 5V regulator, nine general purpose I/O lines and a
sleep mode, where current consumption is reduced to 6µA.
All registered trademarks and trademarks are the property of their respective owners. Protected
by U.S. patents, including 8908779, 9182428, 9270133.
n
n
n
n
n
n
n
n
Measures Up to 18 Battery Cells in Series
2.2mV Maximum Total Measurement Error
Stackable Architecture Supports 100s of Cells
Built-In isoSPI™ Interface
n
1Mb Isolated Serial Communications
n
Uses a Single Twisted Pair, Up to 100 Meters
n
Low EMI Susceptibility and Emissions
n
Bidirectional for Broken Wire Protection
290µs to Measure All Cells in a System
Synchronized Voltage and Current Measurement
16-Bit Delta-Sigma ADC with Programmable
3rd Order Noise Filter
Engineered for ISO 26262-Compliant Systems
Passive Cell Balancing Up to 200mA (Max) with
Programmable Pulse-Width Modulation
9 General Purpose Digital I/O or Analog Inputs
n
Temperature or Other Sensor Inputs
n
Configurable as an I
2
C or SPI Master
6µA Sleep Mode Supply Current
64-Lead eLQFP Package
APPLICATIONS
n
n
n
n
Electric and Hybrid Electric Vehicles
Backup Battery Systems
Grid Energy Storage
High Power Portable Equipment
TYPICAL APPLICATION
2.0
Cell 18 Measurement Error
vs Temperature
1.5
MEASUREMENT ERROR (mV)
1.0
0.5
0
–0.5
–1.0
–1.5
CELL VOLTAGE = 3.3V
5 TYPICAL UNITS
18-Cell Monitor and Balance IC
+
+
+
+
68131 TA01a
CELL 18
CELL 17
•
•
•
LTC6813-1
ISOLATED
DATA WITH
WIRE BREAK
PROTECTION
CELL 2
CELL 1
–2.0
–50
–25
0
25
50
75
TEMPERATURE (°C)
100
125
68131 TA01b
68131f
For more information
www.linear.com/LTC6813-1
1
LTC6813-1
TABLE OF CONTENTS
Features ..................................................... 1
Applications ................................................ 1
Typical Application ........................................ 1
Description.................................................. 1
Absolute Maximum Ratings .............................. 3
Order Information .......................................... 3
Pin Configuration .......................................... 3
Electrical Characteristics ................................. 4
Typical Performance Characteristics ................... 9
Pin Functions .............................................. 15
Block Diagram............................................. 16
Improvements from the LTC6811-1 .................... 17
Operation................................................... 18
State Diagram ......................................................... 18
Core LTC6813-1 State Descriptions ........................ 18
isoSPI State Descriptions ....................................... 19
Power Consumption ............................................... 19
ADC Operation ........................................................20
Data Acquisition System Diagnostics .....................25
Watchdog and Discharge Timer .............................. 32
S Pin Pulse-Width Modulation for Cell Balancing ...33
Discharge Timer Monitor ........................................34
I
2
C/SPI Master on LTC6813-1 Using GPIOs ............34
S Pin Pulsing Using the S Pin Control Settings ...... 39
S Pin Muting ...........................................................40
Serial Interface Overview ........................................40
4-Wire Serial Peripheral Interface (SPI) Physical
Layer.......................................................................40
2-Wire Isolated Interface (isoSPI) Physical Layer ...40
Data Link Layer ....................................................... 51
Network Layer ........................................................ 51
Applications Information ................................ 67
Providing DC Power ................................................ 67
Internal Protection and Filtering..............................68
Cell Balancing ......................................................... 71
Discharge Control During Cell Measurements ........ 72
Digital Communications.......................................... 75
Enhanced Applications............................................82
Reading External Temperature Probes ....................84
Package Description ..................................... 85
Typical Application ....................................... 86
Related Parts .............................................. 86
2
68131f
For more information
www.linear.com/LTC6813-1
LTC6813-1
ABSOLUTE MAXIMUM RATINGS
(Note 1)
PIN CONFIGURATION
IPB
IMB
SCK (IPA)*
CSB (IMA)*
V
–
V
–
**
ICMP
IBIAS
WDT
ISOMD
SDO (NC)*
SDI (NC)*
DTEN
V
REF1
V
REF2
DRIVE
V
+
C18
S18
C17
S17
C16
S16
C15
S15
C14
S14
C13
S13
C12
S12
C11
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
64
63
62
61
60
59
58
57
56
55
54
53
52
51
50
49
TOP VIEW
Total Supply Voltage
V
+
to V
–
............................................................ 112.5V
Supply Voltage (Relative to C12)
V
+
to C12...............................................................50V
Input Voltage (Relative to V
–
)
C0 ............................................................ –0.3V to 6V
C18 .........................–0.3V to MIN (V
+
+ 5.5V, 112.5V)
C(n), S(n) ....................... –0.3V to MIN (8 • n, 112.5V)
IPA, IMA, IPB, IMB........... –0.3V to V
REG
+ 0.3V, ≤ 6V
DRIVE ...................................................... –0.3V to 7V
All Other Pins ........................................... –0.3V to 6V
Voltage Between Inputs
C(n) to C(n–1), S(n) to C(n–1) .................. –0.3V to 8V
C18 to C15, C15 to C12, C12 to C9, C9 to C6, C6 to
C3, C3 to C0 .......................................... –0.3V to 21V
Current In/Out of Pins
All Pins Except V
REG
, IPA, IMA, IPB, IMB, S(n) ..10mA
IPA, IMA, IPB, IMB.............................................30mA
Specified Junction Temperature Range
LTC6813I-1 ..........................................–40°C to 85°C
LTC6813H-1 ....................................... –40°C to 125°C
Junction Temperature ........................................... 150°C
Storage Temperature Range .................. –65°C to 150°C
Device HBM ESD Classification Level 1C
Device CDM ESD Classification Level C5
65
V–
48
47
46
45
44
43
42
41
40
39
38
37
36
35
34
33
V
REG
GPIO9
GPIO8
GPIO7
GPIO6
GPIO5
GPIO4
GPIO3
GPIO2
GPIO1
C0
S1
C1
S2
C2
S3
T
JMAX
= 150°C,
θ
JA
= 17°C/W,
θ
JC
= 2.5°C/W
EXPOSED PAD (PIN 65) IS V
–
, MUST BE SOLDERED TO PCB
*THE FUNCTION OF THESE PINS DEPENDS ON THE CONNECTION OF ISOMD:
ISOMD TIED TO V
–
: CSB, SCK, SDI, SDO
ISOMD TIED TO V
REG
: IPA, IMA, NC, NC
**THIS PIN MUST BE CONNECTED TO V
–
ORDER INFORMATION
TRAY
LTC6813ILWE-1#3ZZPBF
LTC6813HLWE-1#3ZZPBF
PART MARKING*
LTC6813LWE-1
LTC6813LWE-1
http://www.linear.com/product/LTC6813-1#orderinfo
PACKAGE DESCRIPTION
64-Lead Plastic eLQFP
64-Lead Plastic eLQFP
SPECIFIED JUNCTION TEMPERATURE RANGE
–40°C to 85°C
–40°C to 125°C
*The temperature grade is identified by a label on the shipping container.
For more information on lead free part marking, go to:
http://www.linear.com/leadfree/
This part is only offered in trays. For more information go to:
http://www.linear.com/packaging/
S11
C10
S10
C9
S9
C8
S8
C7
S7
C6
S6
C5
S5
C4
S4
C3
LWE PACKAGE
64-LEAD (10mm
×
10mm) PLASTIC eLQFP
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
68131f
For more information
www.linear.com/LTC6813-1
3
LTC6813-1
The
l
denotes the specifications which apply over the full specified
temperature range, otherwise specifications are at T
A
= 25°C. The test conditions are V
+
= 59.4V, V
REG
= 5.0V unless otherwise noted.
The ISOMD pin is tied to the V
–
pin, unless otherwise noted.
SYMBOL
PARAMETER
ADC DC Specifications
Measurement Resolution
ADC Offset Voltage
ADC Gain Error
Total Measurement Error (TME) in
Normal Mode
CONDITIONS
l
ELECTRICAL CHARACTERISTICS
MIN
TYP
0.1
0.1
0.01
0.02
±0.2
MAX
UNITS
mV/Bit
mV
%
%
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
%
°C
%
%
%
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
%
°C
%
%
%
(Note 2)
(Note 2)
C(n) to C(n–1), GPIO(n) to V
–
= 0
C(n) to C(n–1) = 2.0
C(n) to C(n–1), GPIO(n) to V
–
= 2.0, LTC6813I
C(n) to C(n–1), GPIO(n) to V
–
= 2.0, LTC6813H
C(n) to C(n–1) = 3.3
C(n) to C(n–1), GPIO(n) to V
–
= 3.3, LTC6813I
C(n) to C(n–1), GPIO(n) to V
–
= 3.3, LTC6813H
C(n) to C(n–1) = 4.2
C(n) to C(n–1), GPIO(n) to V
–
= 4.2, LTC6813I
C(n) to C(n–1), GPIO(n) to V
–
= 4.2, LTC6813H
C(n) to C(n–1), GPIO(n) to V
–
= 5.0
Sum of Cells
Internal Temperature, T = Maximum Specified
Temperature
V
REG
Pin
V
REF2
Pin
Digital Supply Voltage, V
REGD
C(n) to C(n–1), GPIO(n) to V
–
= 0
C(n) to C(n–1) = 2.0
C(n) to C(n–1), GPIO(n) to V
–
= 2.0, LTC6813I
C(n) to C(n–1), GPIO(n) to V
–
= 2.0, LTC6813H
C(n) to C(n–1) = 3.3
C(n) to C(n–1), GPIO(n) to V
–
= 3.3, LTC6813I
C(n) to C(n–1), GPIO(n) to V
–
= 3.3, LTC6813H
C(n) to C(n–1) = 4.2
C(n) to C(n–1), GPIO(n) to V
–
= 4.2, LTC6813I
C(n) to C(n–1), GPIO(n) to V
–
= 4.2, LTC6813H
C(n) to C(n–1), GPIO(n) to V
–
= 5.0
Sum of Cells
Internal Temperature, T = Maximum Specified
Temperature
V
REG
Pin
V
REF2
Pin
Digital Supply Voltage, V
REGD
l
l
l
l
l
l
l
l
±1.6
±1.8
±2.0
±2.2
±3.0
±3.3
±2.8
±3.8
±4.2
±1
±0.05
±5
–1
–0.05
–0.5
–0.15
0.05
0.5
±0.1
±0.35
l
l
l
l
0
0.20
1.5
±1.6
±1.8
±2.0
±2.2
±3.0
±3.3
±2.8
±3.8
±4.2
Total Measurement Error (TME) in
Filtered Mode
l
l
l
l
l
l
l
±1
±0.05
±5
–1
–0.05
–0.5
–0.15
0.05
0.8
±0.35
l
l
l
0
0.20
1.5
4
68131f
For more information
www.linear.com/LTC6813-1
LTC6813-1
The
l
denotes the specifications which apply over the full specified
temperature range, otherwise specifications are at T
A
= 25°C. The test conditions are V
+
= 59.4V, V
REG
= 5.0V unless otherwise noted.
The ISOMD pin is tied to the V
–
pin, unless otherwise noted.
SYMBOL
PARAMETER
Total Measurement Error (TME) in
Fast Mode
CONDITIONS
C(n) to C(n–1), GPIO(n) to V
–
= 0
C(n) to C(n–1), GPIO(n) to V
–
= 2.0
C(n) to C(n–1), GPIO(n) to V
–
= 3.3
C(n) to C(n–1), GPIO(n) to V
–
= 4.2
C(n) to C(n–1), GPIO(n) to V
–
= 5.0
Sum of Cells
Internal Temperature, T = Maximum Specified
Temperature
V
REG
Pin
V
REF2
Pin
Digital Supply Voltage, V
REGD
C(n) n = 1 to 18
C0
GPIO(n) n = 1 to 9
C(n) n = 0 to 18
GPIO(n) n = 1 to 9
C(n) n = 0 to 18
GPIO(n) n = 1 to 9
MIN
l
l
l
ELECTRICAL CHARACTERISTICS
TYP
±2
MAX
±4
±6
±8.3
l
±10
±0.15
±5
–1.5
–0.18
–2.5
C(n–1)
0
0
–0.15
0.05
–0.4
±0.5
UNITS
mV
mV
mV
mV
mV
%
°C
%
%
%
V
V
V
nA
nA
μA
μA
μA
l
l
l
l
l
l
l
l
Input Range
I
L
Input Leakage Current When Inputs
Are Not Being Measured
Input Current When Inputs Are Being
Measured (State: Core = MEASURE)
10
10
±1
±1
100
1
0.32
2
C(n–1) + 5
1
5
±250
±250
Input Current During Open Wire
Detection
Voltage Reference Specifications
1st Reference Voltage
V
REF1
1st Reference Voltage TC
1st Reference Voltage Thermal
Hysteresis
1st Reference Voltage Long Term
Drift
2nd Reference Voltage
V
REF2
2nd Reference Voltage TC
2nd Reference Voltage Thermal
Hysteresis
2nd Reference Voltage Long Term
Drift
General DC Specifications
V
+
Supply Current
I
VP
(See Figure 1: LTC6813-1 Operation
State Diagram)
l
70
130
V
REF1
Pin, No Load
V
REF1
Pin, No Load
V
REF1
Pin, No Load
V
REF1
Pin, No Load
V
REF2
Pin, No Load
V
REF2
Pin, 5k Load to V
–
V
REF2
Pin, No Load
V
REF2
Pin, No Load
V
REF2
Pin, No Load
l
3.0
3.15
3
20
20
3.3
V
ppm/°C
ppm
ppm/√khr
l
l
2.993
2.992
3
3
10
100
60
3.007
3.008
V
V
ppm/°C
ppm
ppm/√khr
State: Core = SLEEP
,
isoSPI = IDLE
V
REG
= 0V
V
REG
= 0V
V
REG
= 5V
V
REG
= 5V
l
6.1
6.1
3
9
6
0.4
0.375
0.65
0.6
3
14
14
0.55
0.55
0.95
0.95
11
18
5
9
22
28
0.8
0.825
1.35
1.4
µA
µA
µA
µA
µA
µA
mA
mA
mA
mA
68131f
l
l
State: Core = STANDBY
State: Core = REFUP
l
State: Core = MEASURE
l
For more information
www.linear.com/LTC6813-1
5
ADI 工业技术
京公网安备 11010802033920号
Copyright © 2005-2026 EEWORLD.com.cn, Inc. All rights reserved
电子工程世界
