TI1 BQ7692003PWR 15-series cell battery monitor family Datasheet

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bq76920, bq76930, bq76940
SLUSBK2F – OCTOBER 2013 – REVISED NOVEMBER 2015
bq769x0 3-Series to 15-Series Cell Battery Monitor Family
for Li-Ion and Phosphate Applications
1 Introduction
1
1.1
Features
– Undervoltage (UV)
– Secondary protector fault detection
• Additional Features
– Integrated cell balancing FETs
– Charge, discharge low-side NCH FET drivers
– Alert interrupt to host microcontroller
– 2.5-V or 3.3-V output voltage regulator
– No EEPROM programming necessary
– High supply voltage abs max (up to 108 V)
– Simple I2C™ compatible interface (CRC option)
– Random cell connection tolerant
• AFE Monitoring Features
– Pure digital interface
– Internal ADC measures cell voltage, die
temperature, and external thermistor
– A separate, internal ADC measures pack
current (coulomb counter)
– Directly supports up to three thermistors
(103AT)
• Hardware Protection Features
– Overcurrent in discharge (OCD)
– Short circuit in discharge (SCD)
– Overvoltage (OV)
1.2
•
•
Applications
Light Electric Vehicles (LEV): eBikes, eScooters,
Pedelec, and Pedal-Assist Bicycles
Power and Gardening Tools
1.3
•
•
•
Battery Backup and UPS Systems
Wireless Base Station Backup Systems
12-V, 18-V, 24-V, 36-V, and 48-V Battery Packs
Description
The bq769x0 family of robust analog front-end (AFE) devices serves as part of a complete
pack monitoring and protection solution for next-generation, high-power systems, such as light electric
vehicles, power tools, and uninterruptible power supplies. The bq769x0 is designed with low power in
mind: Sub-blocks within the IC may be enabled/disabled to control the overall chip current consumption,
and a SHIP mode provides a simple way to put the pack into an ultra-low power state.
Device Information(1)
PART NUMBER
PACKAGE
BODY SIZE (NOM)
bq76920
TSSOP (20)
6.50 mm × 4.40 mm
bq76930
TSSOP (30)
7.80 mm × 4.40 mm
bq76940
TSSOP (44)
11.00 mm × 4.40 mm
(1) For all available packages, see the orderable addendum at the end of the data sheet.
1.4
Simplified System Diagram
PACK +
Rf
BAT
Rc
Cc
Rc
Cc
Rc
Cc
Rc
Cc
VC5
REGSRC
VC4
REGOUT
VC3
CAP1
VC2
TS1
VC1
SCL
VC0
SDA
SRP
VSS
SRN
CHG
ALERT
DSG
10 kΩ
1 µF
1 µF
Cf
4.7 µF
10k
PUSH-BUTTON FOR BOOT
VCC
Rc
Cc
SCL
SDA
Cc
Rc
0.1 µF
0.1 µF
100
VSS
0.1 µF
100
Rsns
Companion
Controller
GPIO
1M
1M
1M
PACK–
1
An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications,
intellectual property matters and other important disclaimers. UNLESS OTHERWISE NOTED, this document contains
PRODUCTION DATA.
bq76920, bq76930, bq76940
SLUSBK2F – OCTOBER 2013 – REVISED NOVEMBER 2015
www.ti.com
Table of Contents
1
2
3
4
5
Introduction ............................................... 1
Detailed Description ................................... 19
Features .............................................. 1
7.1
Overview
1.2
Applications ........................................... 1
7.2
Functional Block Diagram ........................... 19
1.3
Description ............................................ 1
1.4
Simplified System Diagram ........................... 1
.................................
...........................
7.5
Register Maps .......................................
Application and Implementation ....................
8.1
Application Information ..............................
8.2
Typical Applications .................................
Power Supply Recommendations ..................
Layout ....................................................
10.1 Layout Guidelines ...................................
10.2 Layout Example .....................................
Device and Documentation Support ...............
11.1 Documentation Support .............................
11.2 Related Links ........................................
11.3 Trademarks..........................................
11.4 Electrostatic Discharge Caution .....................
11.5 Glossary .............................................
Revision History .........................................
Description (Continued) ................................
Device Comparison Table..............................
Pin Configuration and Functions .....................
2
4
4
5
.............................................. 5
5.2
bq76920 Pin Diagram ................................ 6
5.3
bq76930 Pin Diagram ................................ 7
5.4
bq76940 Pin Diagram ................................ 9
Electrical Specifications .............................. 11
6.1
Absolute Maximum Ratings ......................... 11
6.2
ESD Ratings ........................................ 11
6.3
Recommended Operating Conditions ............... 11
6.4
Thermal Information ................................. 13
6.5
Electrical Characteristics ............................ 13
6.6
Timing Requirements ............................... 17
6.7
Typical Characteristics .............................. 18
5.1
6
7
1.1
Versions
8
9
10
11
............................................
19
7.3
Feature Description
20
7.4
Device Functional Modes
30
32
42
42
43
49
50
50
50
53
53
53
53
53
53
12 Mechanical, Packaging, and Orderable
Information .............................................. 53
2 Revision History
NOTE: Page numbers for previous revisions may differ from page numbers in the current version.
Changes from Revision E (November 2014) to Revision F
•
•
•
•
•
•
•
•
•
•
•
•
Page
Changed bq7693002 From: Product Preview To Production in the Device Comparison Table............................ 4
Added bq7693007 device to the Device Comparison Table .................................................................... 4
Changed table note to group ground reference in bq76930 Pin Functions ................................................... 7
Changed table note to group ground reference in bq76940 Pin Functions ................................................... 9
Changed 10th cell to 11th cell in the Description of pin 29 ................................................................... 10
Changed table formats for online data sheet ................................................................................... 11
Changed Handing Ratings table to ESD Ratings ............................................................................... 11
Changed note for R1 on Figure 7-3............................................................................................... 26
Added more description to the Communications Subsystem section ........................................................ 29
Changed "SHUTA" to "SHUT_A" and "SHUTB" to "SHUT_B" in the SHIP Mode section ................................ 31
Changed CAUTION verbiage (editorial) .......................................................................................... 31
Changed the SHUT_A, SHUT_B bit descriptions in the SYS_CTRL1 (0x04) table ........................................ 35
Changes from Revision D (July 2014) to Revision E
•
•
•
•
•
•
•
•
•
•
•
•
2
Page
Added a note to the Absolute Maximum Ratings table ........................................................................
Changed the Handling Ratings ....................................................................................................
Added the cross-reference to a new table note at VALERT_IH in Electrical Characteristics .................................
Added a new table note ............................................................................................................
Added the Typical Characteristics section .......................................................................................
Changed the Alert section .........................................................................................................
Changed verbiage in Communications Subsystem ............................................................................
Deleted the READ/WRITE RSVD register in the Register Map ...............................................................
Deleted the READ ONLY register information in the Register Map ..........................................................
Changed the reset for Bit 3 in the PROTECT3 register .......................................................................
Changed wording in the ADCGAIN bit descriptions ...........................................................................
Added Application and Implementation note ....................................................................................
Revision History
11
11
16
16
18
28
29
32
32
37
40
42
Copyright © 2013–2015, Texas Instruments Incorporated
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Product Folder Links: bq76920 bq76930 bq76940
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•
•
•
•
•
•
•
SLUSBK2F – OCTOBER 2013 – REVISED NOVEMBER 2015
Added Design Requirements ......................................................................................................
Added the Detailed Design Procedure ...........................................................................................
Changed the Layout Guidelines ...................................................................................................
Changed the Layout Example ....................................................................................................
Added a Caution ....................................................................................................................
Changed the Good Layout figure .................................................................................................
Changed the Weak Layout figure ................................................................................................
Changes from Revision C (May 2014) to Revision D
•
•
Page
Changed table reference in Integrated Hardware Protections ................................................................ 25
Changed paragraph 4 verbiage of Integrated Hardware Protections ........................................................ 25
Changes from Revision B (April 2014) to Revision C
•
•
•
•
Page
Changed the documentation format ............................................................................................... 1
Changed some devices from Product Preview to Production Data ............................................................ 4
Changed a bit name in the PROTECT1 register ............................................................................... 36
Changed a bit name in the ADCGAIN2 register ................................................................................ 41
Changes from Revision A (December 2013) to Revision B
•
•
•
•
•
•
Page
Changed title of the data manual .................................................................................................. 1
Changed Ordering Information table to ........................................................................................... 4
Changed some devices to Product Preview ...................................................................................... 4
Changed Rf max value in the Recommended Operating Conditions table ................................................. 12
Changed verbiage in mmunications Subsystem ............................................................................... 29
Changed SYS_STAT D6 bit name in the Register Map ....................................................................... 32
Changes from Original (October 2013) to Revision A
•
•
•
•
45
46
50
50
50
51
52
Page
Changed some devices from Product Preview to Production Data ............................................................ 4
Changed the tINDCELL test condition in Electrical Characteristics .............................................................. 14
Deleted duplicate CELLBAL3 table ............................................................................................... 34
Changed bq76940 with bq783xx Companion Controller IC Schematic ...................................................... 45
Copyright © 2013–2015, Texas Instruments Incorporated
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Product Folder Links: bq76920 bq76930 bq76940
Revision History
3
bq76920, bq76930, bq76940
SLUSBK2F – OCTOBER 2013 – REVISED NOVEMBER 2015
www.ti.com
3 Description (Continued)
The bq76920 device supports up to 5-series cells or typical 18-V packs, the bq76930 handles up to 10series cells or typical 36-V packs, and the bq76940 works for up to 15-series cells or typical 48-V packs. A
variety of battery chemistries may be managed with these AFEs, including Lithium Ion, Lithium iron
phosphate, and more.
Via I2C, a host controller can use the bq769x0 to implement many battery pack management functions,
such as monitoring (cell voltages, pack current, pack temperatures), protection (controlling
charge/discharge FETs), and balancing. Integrated A/D converters enable a purely digital readout of
critical system parameters, with calibration handled in TI’s manufacturing process.
4 Device Comparison Table
(1)
TUBE
TAPE & REEL
CELLS
bq7692000PW
bq7692000PWR
bq7692001PW (1)
bq7692001PWR (1)
bq7692002PW (1)
bq7692002PWR (1)
bq7692003PW
bq7692003PWR
bq7692006PW
bq7692006PWR
bq7693000DBT
bq7693000DBTR
bq7693001DBT
bq7693001DBTR
bq7693002DBT
bq7693002DBTR
bq7693003DBT
bq7693003DBTR
bq7693006DBT
bq7693006DBTR
bq7693007DBT
bq7693007DBTR
bq7694000DBT
bq7694000DBTR
bq7694001DBT
bq7694001DBTR
bq7694002DBT
bq7694002DBTR
bq7694003DBT
bq7694003DBTR
bq7694006DBT
bq7694006DBTR
I2C ADDRESS (7-Bit)
LDO (V)
2.5
3–5
0x08
0x18
PACKAGE
No
Yes
No
3.3
20-TSSOP (PW)
Yes
No
2.5
0x08
No
Yes
No
6–10
3.3
0x18
Yes
30-TSSOP (DBT)
No
Yes
2.5
9–15
CRC
0x08
No
Yes
No
3.3
0x18
44-TSSOP (DBT)
Yes
No
Product Preview only
Texas Instruments pre-configures the bq769x0 devices for a specific I2C address, LDO voltage, and more.
These settings are permanently stored in EEPROM and cannot be further modified.
Contact Texas Instruments for other options not listed above, as well as any options noted as “Product
Preview only.”
4
Device Comparison Table
Copyright © 2013–2015, Texas Instruments Incorporated
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SLUSBK2F – OCTOBER 2013 – REVISED NOVEMBER 2015
5 Pin Configuration and Functions
5.1
DSG
Versions
1
20
ALERT
CHG
2
DSG
1
ALERT
DSG
1
44
ALERT
29
SRN
CHG
2
43
SRN
30
CHG
2
19
SRN
VSS
3
18
SRP
VSS
3
28
SRP
VSS
3
42
SRP
SDA
4
17
VC0
SDA
4
27
VC0
SDA
4
41
VC0
16
VC1
SCL
5
26
VC1
SCL
5
40
VC1
15
VC2
TS1
6
25
VC2
TS1
6
39
VC2
24
VC3
CAP1
7
38
VC3
23
VC4
REGOUT
8
37
VC4
22
VC5
REGSRC
9
36
VC5
VC5x
10
35
VC5B
34
VC6
33
VC7
32
VC8
bq76920
20-TSSOP
SCL
5
TS1
6
CAP 1
7
14
VC3
CAP1
7
REGOUT
8
13
VC4
REGOUT
8
REGSRC
9
12
VC5
REGSRC
9
BAT
10
11
NC
VC5x
10
21
VC5B
NC
11
20
VC6
NC
11
NC
12
19
VC7
NC
12
TS2
13
18
VC8
TS2
13
CAP2
14
17
VC9
CAP2
14
31
VC9
BAT
15
16
VC10
VC10x
15
30
VC10
NC
16
29
VC10B
NC
17
28
VC11
bq76930
30-TSSOP
bq76940
44-TSSOP
TS3
18
27
VC12
CAP3
19
26
VC13
BAT
20
25
VC14
NC
21
24
VC15
NC
22
23
NC
Figure 5-1. Pin Versions
bq76920: 3–5 Series Cells (20-TSSOP)
• 6.5 mm x 4.4 mm x 1.2 mm
bq76930: 6–10 Series Cells (30-TSSOP)
• 7.8 mm x 4.4 mm x 1.2 mm
bq76940: 9–15 Series Cells (44-TSSOP)
• 11.3 mm x 4.4 mm x 1.2 mm
Copyright © 2013–2015, Texas Instruments Incorporated
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Pin Configuration and Functions
5
bq76920, bq76930, bq76940
SLUSBK2F – OCTOBER 2013 – REVISED NOVEMBER 2015
5.2
bq76920 Pin Diagram
DSG
1
20
ALERT
CHG
2
19
SRN
VSS
3
18
SRP
SDA
4
17
VC0
SCL
5
16
VC1
TS1
6
15
VC2
CAP 1
7
14
VC3
REGOUT
8
13
VC4
REGSRC
9
12
VC5
11
NC
BAT
5.2.1
www.ti.com
bq76920
20-TSSOP
10
bq76920 Pin Map
bq76920 Pin Functions
(1)
6
PIN
NAME
TYPE
1
DSG
O
Discharge FET driver
DESCRIPTION
2
CHG
O
Charge FET driver
3
VSS
—
Chip VSS
4
SDA
I/O
I2C communication to the host controller
5
SCL
I
I2C communication to the host controller
6
TS1
I
Thermistor #1 positive terminal (1)
7
CAP1
O
Capacitor to VSS
8
REGOUT
P
Output LDO
9
REGSRC
I
Input source for output LDO
10
BAT
P
Battery (top-most) terminal
11
NC
—
No connect
12
VC5
I
Sense voltage for 5th cell positive terminal
13
VC4
I
Sense voltage for 4th cell positive terminal
14
VC3
I
Sense voltage for 3rd cell positive terminal
15
VC2
I
Sense voltage for 2nd cell positive terminal
16
VC1
I
Sense voltage for 1st cell positive terminal
17
VC0
I
Sense voltage for 1st cell negative terminal
18
SRP
I
Negative current sense (nearest VSS)
19
SRN
I
Positive current sense
20
ALERT
I/O
Alert output and override input
If not used, pull down to VSS with a 10-kΩ nominal resistor.
Pin Configuration and Functions
Copyright © 2013–2015, Texas Instruments Incorporated
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5.3
5.3.1
SLUSBK2F – OCTOBER 2013 – REVISED NOVEMBER 2015
bq76930 Pin Diagram
DSG
1
30
ALERT
CHG
2
29
SRN
VSS
3
28
SRP
SDA
4
27
VC0
SCL
5
26
VC1
TS1
6
25
VC2
24
VC3
23
VC4
22
VC5
CAP1
7
REGOUT
8
REGSRC
9
VC5x
10
21
VC5B
NC
11
20
VC6
bq76930
30-TSSOP
NC
12
19
VC7
TS2
13
18
VC8
CAP2
14
17
VC9
BAT
15
16
VC10
bq76930 Pin Map
bq76930 Pin Functions
(1)
PIN
NAME
TYPE
1
DSG
O
Discharge FET driver
DESCRIPTION
2
CHG
O
Charge FET driver
3
VSS
—
Chip VSS
4
SDA
I/O
I2C communication to the host controller
5
SCL
I
I2C communication to the host controller
6
TS1
I
Thermistor #1 positive terminal (1)
7
CAP1
O
Capacitor to VSS
8
REGOUT
P
Output LDO
9
REGSRC
I
Input source for output LDO
10
VC5X
P
Thermistor #2 negative terminal
11
NC
—
No connect (short to CAP2)
12
NC
—
No connect (short to CAP2)
13
TS2
I
Thermistor #2 positive terminal (1)
14
CAP2
O
Capacitor to VC5X
15
BAT
P
Battery (top-most) terminal
16
VC10
I
Sense voltage for 10th cell positive terminal
17
VC9
I
Sense voltage for 9th cell positive terminal
18
VC8
I
Sense voltage for 8th cell positive terminal
19
VC7
I
Sense voltage for 7th cell positive terminal
20
VC6
I
Sense voltage for 6th cell positive terminal
21
VC5B
I
Sense voltage for 6th cell negative terminal
22
VC5
I
Sense voltage for 5th cell positive terminal
23
VC4
I
Sense voltage for 4th cell positive terminal
If not used, pull down to group ground reference (VSS for TS1 and VC5X for TS2) with a 10-kΩ
nominal resistor.
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Pin Configuration and Functions
7
bq76920, bq76930, bq76940
SLUSBK2F – OCTOBER 2013 – REVISED NOVEMBER 2015
www.ti.com
bq76930 Pin Functions (continued)
8
PIN
NAME
TYPE
24
VC3
I
Sense voltage for 3rd cell positive terminal
25
VC2
I
Sense voltage for 2nd cell positive terminal
26
VC1
I
Sense voltage for 1st cell positive terminal
27
VC0
I
Sense voltage for 1st cell negative terminal
28
SRP
I
Negative current sense (nearest VSS)
29
SRN
I
Positive current sense
30
ALERT
I/O
Pin Configuration and Functions
DESCRIPTION
Alert output and override input
Copyright © 2013–2015, Texas Instruments Incorporated
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5.4
5.4.1
SLUSBK2F – OCTOBER 2013 – REVISED NOVEMBER 2015
bq76940 Pin Diagram
DSG
1
44
ALERT
CHG
2
43
SRN
VSS
3
42
SRP
SDA
4
41
VC0
SCL
5
40
VC1
TS1
6
39
VC2
CAP1
7
38
VC3
REGOUT
8
37
VC4
REGSRC
9
36
VC5
VC5x
10
35
VC5B
NC
11
34
VC6
33
VC7
32
VC8
NC
12
TS2
13
bq76940
44-TSSOP
CAP2
14
31
VC9
VC10x
15
30
VC10
NC
16
29
VC10B
NC
17
28
VC11
TS3
18
27
VC12
CAP3
19
26
VC13
BAT
20
25
VC14
NC
21
24
VC15
NC
22
23
NC
bq76940 Pin Map
bq76940 Pin Functions
PIN
(1)
NAME
TYPE
DESCRIPTION
1
DSG
O
Discharge FET driver
2
CHG
O
Charge FET driver
3
VSS
—
Chip VSS
4
SDA
I/O
I2C communication to the host controller
5
SCL
I
I2C communication to the host controller
6
TS1
I
Thermistor #1 positive terminal (1)
7
CAP1
O
Capacitor to VSS
8
REGOUT
P
Output LDO
9
REGSRC
I
Input source for output LDO
10
VC5X
P
Thermistor #2 negative terminal
11
NC
—
No connect (short to CAP2)
12
NC
—
No connect (short to CAP2)
13
TS2
I
Thermistor #2 positive terminal (1)
14
CAP2
O
Capacitor to VC5X
15
VC10X
P
Thermistor #3 negative terminal
If not used, pull down to group ground reference (VSS for TS1, VC5X for TS2, and VC10X for TS3)
with a 10-kΩ nominal resistor.
Copyright © 2013–2015, Texas Instruments Incorporated
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Pin Configuration and Functions
9
bq76920, bq76930, bq76940
SLUSBK2F – OCTOBER 2013 – REVISED NOVEMBER 2015
www.ti.com
bq76940 Pin Functions (continued)
10
PIN
NAME
TYPE
16
NC
—
No connect (short to CAP3)
17
NC
—
No connect (short to CAP3)
18
TS3
I
Thermistor #3 positive terminal (1)
19
CAP3
O
Capacitor to VC10X
20
BAT
P
Battery (top-most) terminal
21
NC
—
No connect
22
NC
—
No connect
23
NC
—
No connect
24
VC15
I
Sense voltage for 15th cell positive terminal
25
VC14
I
Sense voltage for 14th cell positive terminal
26
VC13
I
Sense voltage for 13th cell positive terminal
27
VC12
I
Sense voltage for 12th cell positive terminal
28
VC11
I
Sense voltage for 11th cell positive terminal
29
VC10B
I
Sense voltage for 11th cell negative terminal
30
VC10
I
Sense voltage for 10th cell positive terminal
31
VC9
I
Sense voltage for 9th cell positive terminal
32
VC8
I
Sense voltage for 8th cell positive terminal
33
VC7
I
Sense voltage for 7th cell positive terminal
34
VC6
I
Sense voltage for 6th cell positive terminal
35
VC5B
I
Sense voltage for 6th cell negative terminal
36
VC5
I
Sense voltage for 5th cell positive terminal
37
VC4
I
Sense voltage for 4th cell positive terminal
38
VC3
I
Sense voltage for 3rd cell positive terminal
39
VC2
I
Sense voltage for 2nd cell positive terminal
40
VC1
I
Sense voltage for 1st cell positive terminal
41
VC0
I
Sense voltage for 1st cell negative terminal
42
SRP
I
Negative current sense (nearest VSS)
Positive current sense
43
SRN
I
44
ALERT
I/O
Pin Configuration and Functions
DESCRIPTION
Alert output and override input
Copyright © 2013–2015, Texas Instruments Incorporated
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bq76920, bq76930, bq76940
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SLUSBK2F – OCTOBER 2013 – REVISED NOVEMBER 2015
6 Electrical Specifications
6.1
Absolute Maximum Ratings
Over-operating free-air temperature range (unless otherwise noted)
VBAT
Supply voltage
range
(BAT–VSS)
bq76920
(BAT–VC5x), (VC5x–VSS)
bq76930
(BAT–VC10x), (VC10x–VC5x), (VC5x–VSS)
bq76940
(VCn–VSS) where n = 1..5
bq76920
(VCn–VSS) where n = 1..5, (VCn-VC5x) where n =
6..10
bq76930
(VCn–VSS) where n = 1..5, (VCn–VC5x) where n =
6..10, (VCn–VC10x) where n = 11..15
bq76940
Cell input pins, differential (VCn–VCn–1) where n = 1..15/10/5
(bq76940/bq76930/bq76920, respectively)
Input voltage
range
VI
(VC0–VSS), (CAP1–VSS), (TS1–VSS) (1)
bq76920
(VC0–VSS), (VC5b–VC5x), (CAP2–VC5x),
(CAP1–VSS), (TS2–VC5x), (TS1–VSS) (1)
bq76930
(VC0–VSS), (VC5b–VC5x), (VC10b–VC10x),
(CAP3–VC10x), (CAP2–VC5x), (CAP1–VSS),
(TS3–VC10x), (TS2–VC5x), (TS1–VSS) (1)
bq76940
36
V
–0.3
(n × 7.2)
V
–0.3
9
V
–0.3
3.6
–0.3
36
REGOUT, ALERT
–0.3
3.6
DSG
–0.3
20
CHG
–0.3 VCHGCLAMP
Cell balancing current (per cell)
IDSG
Discharge pin input current when disabled (measured into terminal)
(1)
–0.3
REGSRC
ICB
TSTG
MAX
V
V
bq76920
70
mA
bq76930,
bq76940
5
mA
7
Storage temperature range
–65
Lead temperature (soldering, 10 s)
mA
150
°C
300
The Absolute Maximum Ratings for (TS1–VSS) apply after the device completes POR and should be observed after tBOOTREADY
(10 ms), following the application of the boot signal on TS1. Prior to completion of POR, TS1 should not exceed 5 V.
6.2
ESD Ratings
VALUE
V(ESD)
(1)
(2)
UNIT
SRN, SRP, SCL, SDA
Output voltage
range
VO
MIN
Electrostatic
discharge
Human body model (HBM) ESD stress voltage
(1)
Charged device model (CDM) ESD stress voltage (2)
UNIT
±2
kV
±500
V
JEDEC document JEP155 states that 500-V HBM allows safe manufacturing with a standard ESD control process.
JEDEC document JEP157 states that 250-V CDM allows safe manufacturing with a standard ESD control process.
6.3
Recommended Operating Conditions
Over-operating free-air temperature range (unless otherwise noted). See Section 8.1.1 for more information on cell
configurations. All voltages are relative to VSS, except "Cell input differential."
MIN
VBAT
Supply voltage
range
(BAT–VSS)
bq76920
(BAT–VC5x), (VC5x–VSS)
bq76930
(BAT–VC10x), (VC10x–VC5x),
(VC5x–VSS)
bq76940
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6
TYP
MAX
25
Electrical Specifications
UNIT
V
11
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SLUSBK2F – OCTOBER 2013 – REVISED NOVEMBER 2015
www.ti.com
Recommended Operating Conditions (continued)
Over-operating free-air temperature range (unless otherwise noted). See Section 8.1.1 for more information on cell
configurations. All voltages are relative to VSS, except "Cell input differential."
MIN
Cell input pins, differential (VCn–VCn–1) where n =
1..15/10/5 (bq76940/bq76930/bq76920, respectively),
in-use cells only
TYP
MAX
UNIT
2
5
V
0
5×n
V
–10
10
mV
–200
200
mV
0
3.6
REGSRC
6
25
CHG, DSG
0
16
V
0
3.6
V
(VCn–VSS) where n = 1..5
bq76920
(VCn–VSS) where n = 1..5,
(VCn–VC5x) where n = 6..10
bq76930
(VCn–VSS) where n = 1..5,
(VCn–VC5x) where n = 6..10,
(VCn–VC10x) where n = 11..15
bq76940
SRP
VIN
Input voltage range
(VC0–VSS)
bq76920
(VC0–VSS), (VC5b–VC5x)
bq76930
(VC0–VSS), (VC5b–VC5x),
(VC10b–VC10x)
bq76940
SRN
SCL, SDA
(TS1–VSS)
bq76920
(TS1–VSS), (TS2–VC5x)
bq76930
(TS1–VSS), (TS2–VC5x),
(TS3–VC10x)
bq76940
V
REGOUT, ALERT
VOUT
Output voltage
range
(CAP1–VSS)
bq76920
(CAP1–VSS), (CAP2–VC5x)
bq76930
(CAP1–VSS), (CAP2–VC5x),
(CAP3–VC10x)
bq76940
ICB
Cell balancing
current (internal, per
cell)
RC
External cell input
resistance
CC
External cell input capacitance
Rf
External supply filter resistance
Cf
External supply filter capacitance
RFILT
Sense resistor filter resistance
RALERT
ALERT pin to VSS resistor
CL
REGOUT loading capacitance
CCAP
REGSRC, CAP1, CAP2, and CAP3 output capacitance
1
RTS
External thermistor nominal resistance (103AT) at 25ºC
10K
TOPR
Operating free-air temperature
–40
12
Electrical Specifications
bq76920
0
50
mA
bq76930, bq76940
0
5
mA
bq76920
40
100
1K
bq76930, bq76940
500
1K
1K
Ω
0.1
1
10
µF
40
100
1K
Ω
1
10
40
µF
100
1K
1
Ω
Ω
1M
Ω
4.7
µF
µF
Ω
85
°C
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6.4
SLUSBK2F – OCTOBER 2013 – REVISED NOVEMBER 2015
Thermal Information
Over-operating free-air temperature range (unless otherwise noted)
TSSOP
THERMAL METRIC (1)
RθJA, High K Junction-to-ambient thermal resistance (2)
RθJC(top)
Junction-to-case(top) thermal resistance (3)
(4)
bq76920xy
20 PINS (PW)
bq76930xy
30 PINS (DBT)
bq76940xy
44 PINS (DBT)
93.7
86.5
70.1
28.7
19.4
17.5
RθJB
Junction-to-board thermal resistance
44.6
41.3
33.9
ψJT
Junction-to-top characterization parameter (5)
1.3
0.5
0.5
ψJB
Junction-to-board characterization parameter (6)
44.1
40.6
33.4
n/a
n/a
n/a
RθJC(bottom) Junction-to-case(bottom) thermal resistance
(1)
(2)
(3)
(4)
(5)
(6)
(7)
(7)
UNIT
°C/W
For more information about traditional and new thermal metrics, see the Semiconductor and IC Package Thermal Metrics application
report (SPRA953).
The junction-to-ambient thermal resistance under natural convection is obtained in a simulation on a JEDEC-standard, high-K board, as
specified in JESD51-7, in an environment described in JESD51-2a.
The junction-to-case (top) thermal resistance is obtained by simulating a cold plate test on the package top. No specific JEDECstandard test exists, but a close description can be found in the ANSI SEMI standard G30-88.
The junction-to-board thermal resistance is obtained by simulating in an environment with a ring cold plate fixture to control the PCB
temperature, as described in JESD51-8.
The junction-to-top characterization parameter, ψJT, estimates the junction temperature of a device in a real system and is extracted
from the simulation data for obtaining RθJA, using a procedure described in JESD51-2a (sections 6 and 7).
The junction-to-board characterization parameter, ψJB, estimates the junction temperature of a device in a real system and is extracted
from the simulation data for obtaining RθJA, using a procedure described in JESD51-2a (sections 6 and 7).
The junction-to-case (bottom) thermal resistance is obtained by simulating a cold plate test on the exposed (power) pad. No specific
JEDEC standard test exists, but a close description can be found in the ANSI SEMI standard G30-88.
Spacer
6.5
Electrical Characteristics
Typical conditions are measured at 25ºC with nominal BAT voltages of 18 V (bq76920), 36 V (bq76930), or 48 V (bq76940)
with VCELL = 4 V. Min and max values include full recommended operating condition temperature range from –40ºC to +85ºC.
Certain characteristics may be shown at different voltage or temperature ranges, as clarified in the Test Condition sections.
PARAMETER
DESCRIPTION
TEST CONDITION
MIN
TYP
MAX
40
60
60
90
110
165
130
195
30
45
50
75
10
15
80
120
0.6
1.8
UNIT
SUPPLY CURRENTS
NORMAL mode: ADC off,
CC off
IDD
NORMAL mode: ADC on,
CC off
NORMAL mode: ADC off,
CC on
Sum of ICC_BAT and ICC_REGSRC
currents
NORMAL mode: ADC on,
CC on
ICC_BAT
ICC_REGSRC
ISHIP
NORMAL mode: ADC off
NORMAL mode: ADC on
NORMAL mode: CC off
NORMAL mode: CC on
SHIP/SHUTDOWN mode
Into BAT pin
Into REGSRC pin
Device in full shutdown, only
VSTUP/BG and BOOT detector on
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Electrical Specifications
µA
13
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SLUSBK2F – OCTOBER 2013 – REVISED NOVEMBER 2015
www.ti.com
Electrical Characteristics (continued)
Typical conditions are measured at 25ºC with nominal BAT voltages of 18 V (bq76920), 36 V (bq76930), or 48 V (bq76940)
with VCELL = 4 V. Min and max values include full recommended operating condition temperature range from –40ºC to +85ºC.
Certain characteristics may be shown at different voltage or temperature ranges, as clarified in the Test Condition sections.
PARAMETER
DESCRIPTION
TEST CONDITION
MIN
TYP
MAX
–5
±2.5
5
–1.0
±0.1
1.0
15
25
±0.1
0.3
UNIT
LEAKAGE AND OFFSET CURRENTS
dINOM
NORMAL mode supply
current offset
dISHIP
SHIP mode supply
current offset
dIALERT
Supply current when
ALERT active
dICELL
Cell measurement input
current
ILKG
Terminal input leakage
Measured into VC5x (bq76930,
bq76940) and VC10x (bq76940)
Measured into VC5x (bq76930,
bq76940) or added to BAT (bq76920)
Measured into VC0–VC15 except VC5,
VC10, VC15
–0.3
Measured into VC5, VC10, VC15
µA
0.5
1
INTERNAL POWER CONTROL (STARTUP and SHUTDOWN)
VPORA
Analog POR threshold
See Note (1)
VSHUT
Shutdown voltage
See Note (1)
tI2CSTARTUP
Time delay after boot
signal on TS1 before I2C
communications allowed
Delay after boot sequence when I2C
communication is allowed
tBOOTREADY
Device boot startup delay
Delay after boot signal when device has
completed full boot-up sequence
TSHUTD
Thermal shutdown
voltage
4
5
V
3.6
V
1
100
ms
10
ms
150
°C
MEASUREMENT SCHEDULE
tVCELL
Cell voltage measurement
bq76920, bq76930, bq76940
interval
tINDCELL
Individual cell
measurement time
tCB_RELAX
Cell balancing relaxation
time before cell voltage
measured
tTEMP_DEC
Temperature
measurement decimation
time
tBAT
Pack voltage calculation
interval
tTEMP
Temperature
measurement interval
250
Per cell, balancing off
50
Per cell, balancing on
12.5
12.5
Measurement duration for temperature
reading
ms
12.5
250
Period of measurement of either
TS1/TS2/TS3 or internal die temp
2
s
14-BIT ADC FOR CELL VOLTAGE AND TEMPERATURE MEASUREMENT
ADCRANGE
ADC measurement
recommend operation
range
ADCLSB
ADC LSB value
ADC25A
ADC25B
ADC cell voltage
accuracy
ADC25C
VCELL measurements
2
5
V
TS/Temp measurements
0.3
3
V
VCELL = 3.6 – 4.3 V
–40
±10
40
VCELL = 3.2 – 4.6 V
–40
±15
40
VCELL = 2.0 – 5.0 V
–50
±25
50
382
µV
ADC60
ADC cell voltage
accuracy temperature drift TA = 0ºC to 60ºC
adder from 25°C
–10
10
ADCTS
ADC thermistor
measurement accuracy
–35
35
(1)
14
mV
Input from 0.3 to 3.0 V, BAT > 7 V
Measured at BAT pin, rising.
Electrical Specifications
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SLUSBK2F – OCTOBER 2013 – REVISED NOVEMBER 2015
Electrical Characteristics (continued)
Typical conditions are measured at 25ºC with nominal BAT voltages of 18 V (bq76920), 36 V (bq76930), or 48 V (bq76940)
with VCELL = 4 V. Min and max values include full recommended operating condition temperature range from –40ºC to +85ºC.
Certain characteristics may be shown at different voltage or temperature ranges, as clarified in the Test Condition sections.
PARAMETER
DESCRIPTION
TEST CONDITION
MIN
TYP
MAX
UNIT
16-BIT CC FOR PACK CURRENT MEASUREMENT
CCRANGE
CC input voltage range
–200
200
mV
CCFSR
CC full scale range
–270
270
mV
CCLSB
CC LSB value
CC running constantly
8.44
µV
tCCREAD
Conversion time
Single conversion
250
ms
CCINL
Integral nonlinearity
16-bit, best fit over input voltage range
± 200 mV
±2
CCOFFSET
Offset error
CCGAIN
Gain error
Over input voltage range
CCGAINDRIFT
Gain error drift
Over input voltage range
CCRIN
Effective input resistance
± 40
LSB
±1
±3
LSB
± 0.5%
± 1.5%
FSR
150
PPM / °C
2.5
MΩ
THERMISTOR BIAS
RTS
Pull-up resistance
TA = 25°C
RTSDRIFT
Pull-up resistance across
temp
9.85
TA = –40°C to 85°C
VDIETEMP25
Die temperature voltage
TA = 25°C
VDIETEMPDRIFT
Die temperature voltage
drift
10
9.7
10.15
kΩ
10.3
kΩ
DIETEMP
1.20
V
–4.2
mV/°C
INTEGRATED HARDWARE PROTECTIONS
OVRANGE
OV threshold range
0x2008
0x2FF8
ADC
UVRANGE
UV threshold range
0x1000
0x1FF0
ADC
OVUVSTEP
OV and UV threshold step
size
UVMINQUAL
UV minimum value to
qualify
OVDELAY
UVDELAY
OV delay timer options
UV delay timer options
Below UVMINQUAL, cell is shorted
(unused)
OCD threshold options
OCDSTEP
OCD threshold step size
OCDDELAY
OCD delay options
SCDRANGE
SCDSTEP
SCDDELAY
(2)
(3)
SCD threshold options
SCD threshold step size
LSB
0x0518
ADC
OV delay = 1 s
0.7
1
1.75
OV delay = 2 s
1.6
2
2.75
OV delay = 4 s
3.5
4
5
OV delay = 8 s
7
8
10
UV delay = 1 s
0.7
1
1.75
UV delay = 4 s
3.5
4
5
UV delay = 8 s
7
8
10
14
16
20
UV delay = 16 s
OCDRANGE
16
Measured across (SRP–SRN)
(2)
8
100
RSNS = 0
2.78
RSNS = 1
5.56
See Note
(3)
Measured across (SRP–SRN)
8
(2)
22
s
mV
mV
mV
1280
ms
200
mV
RSNS = 0
11.1
mV
RSNS = 1
22.2
mV
SCD delay options
35
70
105
µs
50
100
150
µs
140
200
260
µs
280
400
520
µs
Values indicate nominal thresholds only. For Min and Max variation, apply OCOFFSET and OCSCALERR.
Values indicate nominal thresholds only. For Min and Max variation, apply tPROTACC.
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Electrical Specifications
15
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SLUSBK2F – OCTOBER 2013 – REVISED NOVEMBER 2015
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Electrical Characteristics (continued)
Typical conditions are measured at 25ºC with nominal BAT voltages of 18 V (bq76920), 36 V (bq76930), or 48 V (bq76940)
with VCELL = 4 V. Min and max values include full recommended operating condition temperature range from –40ºC to +85ºC.
Certain characteristics may be shown at different voltage or temperature ranges, as clarified in the Test Condition sections.
PARAMETER
DESCRIPTION
tPROTACC
Delay accuracy for OCD
OCOFFSET
OCD and SCD voltage
offset
OCSCALEERR
OCD and SCD scale
accuracy
TEST CONDITION
MIN
TYP
MAX
–20%
20%
–2.5
2.5
–10%
10%
UNIT
mV
CHARGE AND DISCHARGE DRIVERS
VFETON
CHG and DSG on
REGSRC ≥ 12 V with load resistance of
10 MΩ
10
12
14
V
REGSRC < 12 V with load resistance of
10 MΩ
REGSRC
–2
REGSRC
–1
REGSRC
V
tFET_ON
CHG and DSG ON rise
time
CHG/DSG driving an equivalent load
capacitance of 10 nF, measured from
10% to 90% of VFETON
200
250
µs
tDSG_OFF
DSG pull-down OFF fall
time
DSG driving an equivalent load
capacitance of 10 nF, measured from
90% to 10%
60
90
µs
RCHG_OFF
CHG pull-down OFF
resistance to VSS
When CHG disabled, CHG held at 12 V
750
1000
1250
kΩ
RDSG_OFF
DSG pull-down OFF
resistance to VSS
When DSG disabled, DSG held at 12 V
1.75
2.50
4.25
kΩ
VLOAD_DETECT
Load detection threshold
0.4
0.7
1.0
V
18
20
22
V
CHG clamp voltage
If the CHG pin externally pulled high
(through PACK–, if load applied),
500 µA max sink current into CHG pin.
With CHG_ON bit cleared.
VALERT_OH
ALERT output voltage
high
IOL = 1 mA
VALERT_OL
ALERT output voltage low Unloaded
VALERT_IH
ALERT input high
RALERT_PD
ALERT pin weak
Measured into ALERT pin with ALERT
pulldown resistance when
= REGOUT
driven low
VCHG_CLAMP
ALERT PIN
REGOUT x
0.75
ALERT externally forced high when
internally driven low. See note (4).
V
1
REGOUT
x 0.25
V
1.5
V
0.8
2.5
8
MΩ
1
5
10
Ω
CELL BALANCING DRIVER
RDSFET
Internal cell balancing
driver resistance
VCELL = 3.6 V
XBAL
Cell balancing duty cycle
when enabled
Every 250 ms
70%
EXTERNAL REGULATOR
External LDO voltage
options
Nominal values, TI factory programmed,
unloaded, across temp
VEXTLDO_LN
Line regulation
REGSRC pin stepped from 6 to 25 V,
with 10 mA load, in 100 µs
VEXTLDO_LD
Load regulation
IREGOUT = 0 mA to 10 mA
VEXTLDO
(4)
16
External LDO minimum
voltage under DC load
2.50
2.55
V
3.20
3.30
3.40
V
100
mV
–4%
REGOUT = 10 mA DC, 2.5-V version
VEXTLDO_DC
2.45
4%
2.4
V
REGOUT = 20 mA DC, 2.5-V version
2.3
V
REGOUT = 10 mA DC, 3.3-V version
3.15
V
REGOUT = 20 mA DC, 3.3-V version
3.05
V
MIN specifies the threshold below which the device will never register that an external alert has occurred. MAX specifies the minimum
threshold above which the device will always register that an external alert has occurred.
Electrical Specifications
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SLUSBK2F – OCTOBER 2013 – REVISED NOVEMBER 2015
Electrical Characteristics (continued)
Typical conditions are measured at 25ºC with nominal BAT voltages of 18 V (bq76920), 36 V (bq76930), or 48 V (bq76940)
with VCELL = 4 V. Min and max values include full recommended operating condition temperature range from –40ºC to +85ºC.
Certain characteristics may be shown at different voltage or temperature ranges, as clarified in the Test Condition sections.
PARAMETER
IEXTLDO_LIMIT
DESCRIPTION
TEST CONDITION
MIN
TYP
MAX
30
38
45
mA
300
1000
mV
10
2000
µs
External LDO current limit REGOUT = 0 V
UNIT
BOOT DETECTOR
Measured at TS1 pin with device in
SHIP mode. Below MIN, device will not
boot up. Above MAX, device will be
guaranteed to boot up.
VBOOT
Boot threshold voltage
tBOOT_max
Measured at TS1 pin. Below MIN,
Boot threshold application
device will not boot up. Above MAX,
time
device will be guaranteed to boot up.
6.6
Timing Requirements
2
I C COMPATIBLE INTERFACE
MIN
TYP
MAX
UNIT
REGOUT x
0.25
VIL
Input Low Logic Threshold
V
VIH
Input High Logic Threshold
VOL
Output Low Logic Drive
0.20
tf
SCL, SDA Fall Time
0.40
VOH
Output High Logic Drive (Not applicable due to open-drain outputs)
N/A
tHIGH
SCL Pulse Width High
4.0
µs
tLOW
SCL Pulse Width Low
4.7
µs
tSU;STA
Setup time for START condition
4.7
µs
tHD;STA
START condition hold time after which first clock pulse is generated
4.0
µs
tSU;DAT
Data setup time
250
ns
tHD;DAT
Data hold time
0
µs
tSU;STO
Setup time for STOP condition
4.0
µs
tBUF
Time the bus must be free before new transmission can start
4.7
tVD;DAT
Clock Low to Data Out Valid
tHD;DAT
Data Out Hold Time After Clock Low
0
fSCL
Clock Frequency
0
REGOUT x
0.75
V
V
N/A
V
µs
900
ns
ns
100
kHz
SCL
SDA
SCL
SDA
SCL
SDA
Figure 6-1. I2C Timing
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Electrical Specifications
17
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SLUSBK2F – OCTOBER 2013 – REVISED NOVEMBER 2015
Typical Characteristics
0.020
VCx Error (mV)
30
VC1 Error
0.018
0.016
VC2 Error
0.014
VC3 Error
0.012
VC4 Error
0.010
VC5 Error
25
Gain Error (PPM)
6.7
www.ti.com
0.008
0.006
0.004
20
15
10
5
0.002
0.000
0
±0.002
±0.004
2.00 2.30 2.60 2.90 3.20 3.50 3.80 4.10 4.40 4.70 5.00
VCx Input (V)
±5
±40
35
60
Temperature (ƒC)
Figure 6-2. bq76930 VCx Error Across Input Range at 25°C with
VIN at 3.6 V
85
C005
Figure 6-3. Coulomb Counter Gain Error Temperature Drift
(from –0.2 V to 0.2 V)
0.0
0.0
±0.1
±0.2
±0.4
±0.2
Offset (uV)
Gain Error (%FSR)
10
±15
C001
±0.3
±0.4
±0.5
±0.6
±0.8
±1.0
±1.2
±0.6
±1.4
±0.7
±1.6
±40
±15
10
35
60
85
Temperature (ƒC)
±40
10
±15
35
60
Temperature (ƒC)
C003
Figure 6-4. Coulomb Counter Gain Error
(from –0.2 V to 0.2 V)
85
C002
Figure 6-5. Coulomb Counter Offset
0.01
OV Detection Error (V)
0.01
0.00
±0.01
±0.01
±0.02
±0.02
±40
±15
10
35
60
85
Temperature (ƒC)
C004
Figure 6-6. OV Protection Detection Error (0xFF Setting)
18
Electrical Specifications
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7 Detailed Description
7.1
Overview
In the bq769x0 family of analog front-end (AFE) devices, the bq76920 device supports up to 5-series cells,
the bq76930 device supports up to 10-series cells, and the bq76940 device supports up to 15-series cells.
Via I2C, a host controller can use the bq769x0 to implement battery pack management functions, such as
monitoring (cell voltages, pack current, pack temperatures), protection (controlling charge/discharge
FETs), and balancing. Integrated A/D converters enable a purely digital readout of critical system
parameters including cell voltages and internal or external temperature, with calibration handled in TI’s
manufacturing process. For an additional degree of pack reliability, the bq769x0 includes hardware
protections for voltage (OV, UV) and current (OCD, SCD).
The bq769x0 provides two low-side FET drivers, charge (CHG) and discharge (DSG), which may be used
to directly manipulate low-side power NCH FETs, or as signals that control an external circuit that enables
high-side PCH or NCH FETs. A dedicated ALERT input/output pin serves as an interrupt signal to the host
microcontroller, quickly informing the microcontroller of an updated status in the AFE. This may include a
fault event or that a coulomb counter sample is available for reading. An available ALERT pin may also be
driven externally by a secondary protector to provide a redundant means of disabling the CHG and DSG
signals and higher system visibility.
7.2
Functional Block Diagram
REG
SRC
CAP
Bandgap
IBIAS
VSTUP/POR
BAT
Cell Balance
Drivers/FETs
BOOT
Internal 3.3-V
LDO
ALERT
256 kHz
Digital core
Die temp
REG
OUT
14-bit ADC
Modulator
V2I
VCx Inputs
External
2.5/3.3-V LDO
CC VREF
FET
DRIVER and
LOAD
DETECT
CHG
DSG
TS
16-bit ACC
Modulator
SCL
I2C
SDA
TS
VSS
BOOT
SCD
comp
To POR
OCD
comp
EEPROM
SRP SRN
Figure 7-1. Functional Block Diagram
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7.3
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Feature Description
7.3.1
Subsystems
bq769x0 consists of three major subsystems: Measurement, Protection, and Control. These work together
to ensure that the fundamental battery pack parameters—voltage, current and temperature—are
accurately captured and easily available to a host controller, while ensuring a baseline or secondary level
of hardware protection in the event that a host controller is unable or unavailable to manage certain fault
conditions.
NOTE
The bq769x0 is intended to serve as an analog front-end (AFE) as part of a chipset system
solution: A companion microcontroller is required to oversee and control this AFE.
•
•
•
The Measurement subsystem’s core responsibility is to digitize the cell voltages, pack current
(integrated into a passed charge calculation), external thermistor temperature, and internal die
temperature. It also performs an automatic calculation of the total battery stack voltage, by simply
adding up all measured cell voltages.
The Protection subsystem provides a baseline or secondary level of hardware protections to better
support a battery pack’s FMEA requirements in the event of a loss of host control or simply if a host is
unable to respond to a certain fault event in time. Integrated protections include pack-level faults such
as OV, UV, OCD, SCD, detection of an external secondary protector fault, and internal logic
“watchdog”-style device fault (XREADY). Protection events will trigger toggling of the ALERT pin, as
well as automatic disabling of the DSG and/or CHG FET driver (depending on the fault). Recovery
from a fault event must be handled by the host microcontroller.
The Control subsystem implements a suite of useful pack features, including direct low-side NCH FET
drivers, cell balancing drivers, the ALERT digital output, an external LDO and more.
The following sections describe each subsystem in greater detail, as well as explaining the various power
states that are available.
7.3.1.1
Measurement Subsystem Overview
The monitoring subsystem ensures that all cell voltages, temperatures, and pack current may be easily
measured by the host. All ADCs are trimmed by TI.
ADC and CC data are always returned as atomic values if both high and low registers are read in the
same transaction (using address auto-increment).
7.3.1.1.1 Data Transfer to the Host Controller
The bq769x0 has a fully digital interface: All information is transferred through I2C, simply by reading
and/or writing to the appropriate register(s) storing the relevant data. Block reads and writes, buffered by
an 8-bit CRC code per byte, ensure a fast and robust transmission of data.
7.3.1.1.2 14-Bit ADC
Each bq769x0 device measures cell voltages and temperatures using a 14-bit ADC. This ADC measures
all differential cell voltages, thermistors and/or die temperature with a nominal full-scale unsigned range of
0–6.275 V and LSB of 382 µV.
To enable the ADC, the [ADC_EN] bit in the SYS_CTRL1 register must be set. This bit is set automatically
whenever the device enters NORMAL mode. When enabled, the ADC ensures that the integrated OV and
UV protections are functional.
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For each contiguous set of five cells (VC1 to VC5, VC6 to VC10), when no cells in that particular set are
being balanced, each cell is measured over a 50-ms decimation window and a complete update is
available every 250 ms. In the bq76930 and bq76940, every set of five cells above the primary five cells is
measured in parallel. The 50-ms decimation greatly assists with removing the aliasing effects present in a
noisy motor environment.
When any cells in a contiguous set of 5 cells are being balanced, those affected cells are measured in a
reduced 12.5-ms decimation period, to allow the cell balancing to function properly without affecting the
integrated OV and UV protections. Since cell balancing is typically only performed during pack charge or
idle periods, the shortened decimation periods should not impact accuracy as the system noise during
these times is greatly reduced. This reduced decimation period is only applied to sets where one of the
cells is being balanced. The following summarizes this for the bq76920–bq76940 devices:
• VC1 to VC5 measurements are each taken in a 50-ms decimation period when all bits in CELLBAL1
register are 0, and a 12.5-ms decimation period when any bits in CELLBAL1 register are 1.
• VC6 to VC10 measurements are each taken in a 50-ms decimation period when all bits in CELLBAL2
register are 0, and a 12.5-ms decimation period when any bits in CELLBAL2 register are 1.
• VC11 to VC15 measurements are each taken in a 50-ms decimation period when all bits in CELLBAL3
register are 0, and a 12.5-ms decimation period when any bits in CELLBAL3 register are 1.
• Total update interval is 250 ms.
Each differential cell input is factory-trimmed for gain and/or offset, such that the resulting reading via I2C
is always consistent from part-to-part and requires no additional calibration or correction factor application.
The ADC is required to be enabled in order for the integrated OV and UV protections to be operating.
The following shows how to convert the 14-bit ADC reading into an analog voltage. Each device is factory
calibrated, with a GAIN and OFFSET stored into EEPROM.
The ADC transfer function is a linear equation defined as follows:
V(cell) = GAIN x ADC(cell) + OFFSET
(1)
GAIN is stored in units of µV/LSB, while OFFSET is stored in mV units.
Some example cell voltage calculations are provided in the table below. For illustration purposes, the
example uses a hypothetical GAIN of 380 µV/LSB (ADCGAIN<4:0> = 0x0F) and OFFSET of 30 mV
(ADCOFFSET<7:0> = 0x1E).
14-Bit ADC Result
ADC Result in Decimal
GAIN (µV/LSB)
OFFSET (mV)
Cell Voltage (mV)
0x1800
6144
380
30
2365
0x1F10
7952
380
30
3052
NOTE
When entering NORMAL mode from SHIP mode, please allow for the following times before
reading out initial cell voltage data:
bq76920: 250 ms
bq76930: 400 ms
bq76940: 800 ms
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7.3.1.1.2.1 Optional Real-time Calibration Using the Host Microcontroller
The performance of the cell voltage values measured by the 14-bit ADC has a factory-calibrated accuracy,
as follows:
• +/– 10 mV TYP, +/– 40 mV MIN and MAX from 3.6 to 4.3 V,
• +/– 15 mV TYP, +/– 40 mV MIN and MAX from 3.2 to 4.6 V, and
• +/– 50 mV MIN and MAX from 2.0 to 5.0 V
While this is suitable for the majority of pack protection and basic monitoring applications the bq769x0
AFE family is intended to support, certain systems may require a higher accuracy performance.
To achieve this, use an available ADC channel and general purpose output terminal on the host
microcontroller paired with the bq769x0. A simple external circuit consisting of two precision resistors and
a small-signal FET is activated by the host microcontroller to determine the total stack voltage, VSTACK.
This is then compared against the sum of the individual cell voltages as measured by the internal ADC of
the bq769x0. The resulting transfer function coefficient, GAIN2, is simply applied to each cell voltage ADC
value for improved accuracy.
Battery cell stack
Host microcontroller
A/D input
Gen. purpose output
Figure 7-2. External Real-Time Calibration Circuit to Host Microcontroller
The process is as follows:
1. Periodically measure VSTACK.
(a) VSTACK = VAD × (R1 + R2) / R1
2. Read out all VCELL ADC readings from the bq769x0 and apply the standard GAIN and OFFSET values
stored in the bq769x0.
(a) V(1) = GAIN x ADC1 + OFFSET, V(2) = GAIN x ADC2 + OFFSET, and so on
3. Sum up all VCELL values, VSUM.
(a) VSUM = V(1) + V(2) + V(3) …
4. Calculate GAIN2.
(a) GAIN2 = VSTACK / VSUM
As a general recommendation, a new GAIN2 function should be generated when the cell voltages increase
or decrease by more than 100 mV. With GAIN2, each cell voltage calculation becomes:
V(cell) = GAIN2 × (GAIN x ADC(cell) + OFFSET)
(2)
For systems that do not require this additional in-use calibration function, GAIN2 is simply “1”.
22
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7.3.1.1.3 16-Bit CC
A 16-bit integrating ADC, commonly referred to as the coulomb counter (CC), provides measurements of
accumulated charge across the current sense resistor. The integration period for this reading is 250 ms.
The CC may be operated in one of two modes: ALWAYS ON and 1-SHOT.
• In ALWAYS ON mode, the CC runs at 100%, gathering a fresh reading every 250 ms. The conclusion
of each reading sets the CC_READY bit, which toggles the ALERT pin high to inform the
microcontroller that a new reading is available. To enable Always On mode, set [CC_EN] = 1.
• In 1-SHOT mode, the CC performs a single 250-ms reading, and similarly sets the CC_READY bit
when completed. This mode is intended for non-gauging usages, where the host simply desires to
check the pack current.
To enable a 1-SHOT reading, ensure [CC_EN] = 0 and set [CC_ONESHOT] = 1.
The full scale range of the CC is ± 270 mV, with a max recommended input range of ± 200 mV, thus
yielding an LSB of approximately 8.44 µV.
The following equation shows how to convert the 16-bit CC reading into an analog voltage if no boardlevel calibration is performed:
CC Reading (in µV) = [16-bit 2’s Complement Value] × (8.44 µV/LSB)
16-Bit CC Result
ADC Result in Decimal
(3)
CC Reading (in µV)
0x0001
1
8.44
0x2710
10000
84,400
0x7D00
32000
270,080
0x8300
–32000
–270,080
0xC350
–15536
–131,123.84
0xFFFF
–1
–8.44
7.3.1.1.4 External Thermistor
One (bq76920), two (bq76930), or three (bq76940) 10 kΩ NTC 103AT thermistors may be measured by
the device. These are measured by applying a factory-trimmed internal 10k pull-up resistance to an
internal regulator value of nominally 3.3 V, the result of which can be read out from the TSx (TS1, TS2,
TS3) registers.
To select thermistor measurement mode, set [TEMP_SEL] = 1.
Thermistor TS1 is connected between TS1 and VSS; TS2 is connected between TS2 and VC5x (bq76930
and bq76940 only); and TS3 is connected between TS3 and VC10x (bq76940 only). These thermistors
may be placed in various areas in the battery pack to measure such things as localized cell temperature,
FET heating, etc.
The thermistor impedance may be calculated using the 14-bit ADC reading in the TS1/TS2/TS3 registers
and 10k internal pull-up resistance as follows:
The following equations show how to use the 14-bit ADC readings in TS1, TS2, and TS3 to determine the
resistance of the external 103AT thermistor:
VTSX = (ADC in Decimal) x 382 µV/LSB
RTS = (10,000 × VTSX) ÷ (3.3 – VTSX)
(4)
(5)
To convert the thermistor resistance into temperature, please refer to the thermistor component
manufacturer’s datasheet.
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7.3.1.1.5 Die Temperature Monitor
NOTE
When switching between external and internal temperature monitoring, a 2-s latency may be
incurred due to the natural scheduler update interval.
A die temperature block generates a voltage that is proportional to the die temperature, and provides a
way of reducing component count if pack thermistors are not used or ensuring that the die power
dissipation requirements are observed. The die is measured using the same on-board 14-bit ADC as the
cell voltages.
To select internal die temperature measurement mode, set [TEMP_SEL] = 0.
For bq76930 and bq76940, multiple die temperature measurements are available. These are stored in
TS2 and TS3.
To convert a DIETEMP reading into temperature, refer to the following equation box. If more accurate
temperature readings are needed from DIETEMP, the DIETEMP at room temperature value should be
stored during production calibration.
The following equation shows how to use the 14-bit ADC readings in TS1, TS2, and TS3 when
[TEMPSEL] = 0 to determine the internal die temperature:
V25 = 1.200 V (nominal)
VTSX = (ADC in Decimal) x 382 µV/LSB
TEMPDIE = 25° – ((VTSX – V25) ÷ 0.0042)
(6)
(7)
(8)
7.3.1.1.6 16-Bit Pack Voltage
Once converted to digital form, each cell voltage is added up and the summation result stored in the BAT
registers. This 16-bit value has a nominal LSB of 1.532 mV.
The following shows how to convert the 16-bit pack voltage ADC reading into an analog voltage. This
value also uses the GAIN and OFFSET stored into EEPROM.
The ADC transfer function is a linear equation defined as follows:
V(BAT) = 4 x GAIN x ADC(cell) + (#Cells x OFFSET)
(9)
GAIN is stored in units of µV/LSB, while OFFSET is stored in mV units.
7.3.1.1.7 System Scheduler
A master scheduler oversees the monitoring intervals, creating a full update every 250 ms. Temperature
measurements are taken every 2 seconds. Pack voltage is calculated every 250 ms.
7.3.1.2
Protection Subsystem
7.3.1.2.1 Integrated Hardware Protections
Integrated hardware protections are provided as an extra degree of safety and are meant to supplement
the standard protection feature set that would be incorporated into the host controller firmware. They
should not be used as the sole means of protecting a battery pack, but are useful for FMEA purposes; for
example, in the event that a host microcontroller is unable to react to any of the below protection
situations. All hardware protection thresholds and delays should be loaded into the AFE by the host
microcontroller during system startup. The AFE will also default to pre-defined threshold and delay
settings, in case the host microcontroller is unable to or does not wish to program the protection settings.
24
Detailed Description
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Overcurrent in Discharge (OCD) and Short Circuit in Discharge (SCD) are implemented using sampled
analog comparators that run at 32 kHz, and that continuously monitor the voltage across (SRP–SRN)
while the device is in NORMAL mode. Upon detection of a voltage that exceeds the programmed OCD or
SCD threshold, a counter begins to count up to a programmed delay setting. If the counter reaches its
target value, the SYS_STAT register is updated to indicate the fault condition, the FET state(s) are
updated as shown in
Table 7-1, and the ALERT pin is driven high to interrupt the host.
The protection fault threshold and delay settings for OCD and SCD protections are configured via the
PROTECT1 and PROTECT2 registers. See Section 7.5 for details about supported values.
Overvoltage (OV) and Undervoltage (UV) protections are handled digitally, by comparing the cell voltage
readings against the 8-bit programmed thresholds in the OV and UV registers.
The OV threshold is stored in the OV_TRIP register and is a direct mapping of 8 bits of the 14-bit ADC
reading, with the upper 2 MSB preset to “10” and lower 4 LSB preset to “1000”. In other words, the
corresponding OV trip level is mapped to “10-XXXX-XXXX–1000”. The programmable range of OV
thresholds is approximately 3.15 to 4.7 V, but this is subject to variation due to
the (GAIN, OFFSET) linear equation used to map the ADC values.
The UV threshold is stored in the UV_TRIP register and is a direct mapping of 8 bits of the 14-bit ADC
reading, with the upper 2 MSB preset to “01” and lower 4 LSB preset to “0000”. In other words, the
corresponding OV trip level is mapped to “01-XXXX-XXXX–0000”. The programmable range of UV
thresholds is approximately 1.58 to 3.1 V, but this is subject to variation due to the (GAIN, OFFSET) linear
equation used to map the ADC values.
Protection
Upper 2 MSB
Middle 8 Bits
Lower 4 LSB
OV
10
Set in OV_TRIP Register
1000
UV
01
Set in UV_TRIP Register
0000
NOTE
To support flexible cell configurations within bq76920, bq76930, and bq76940, UV is ignored
on any cells that have a reading under UVMINQUAL. This allows cell pins to be shorted in
implementations where not all cells are needed (for example, 6-series cells using the
bq76930).
Default protection thresholds and delays are shown in the register description at the end of this datasheet.
These are loaded into the digital register (RAM) of the device when the device enters NORMAL mode.
These RAM values may then be overwritten by the host controller to any other values, which they will
retain until a POR event. It is recommended that the host controller reload these values during its standard
power-up and/or re-initialization sequence.
To calculate the correct OV_TRIP and UV_TRIP register values for a device, use the following procedure:
1. Determine desired OV.
2. Read out [ADCGAIN] and [ADCOFFSET] from their corresponding registers. Note that ADCGAIN is
stored in units of µV/LSB, while ADCOFFSET is stored in mV.
3. Calculate the full 14-bit ADC value needed to meet the desired OV and UV trip thresholds as follows:
(a) OV_TRIP_FULL = (OV – ADCOFFSET) ÷ ADCGAIN
(b) UV_TRIP_FULL = (UV – ADCOFFSET) ÷ ADCGAIN
4. Remove the upper 2 MSB and lower 4 LSB from the full 14-bit value, retaining only the remaining
middle 8 bits. This can be done by shifting the OV_TRIP_FULL and UV_TRIP_FULL binary values 4
bits to the right and removing the upper 2 MSB.
5. Write OV_TRIP and UV_TRIP to their corresponding registers.
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Both OV and UV protections require the ADC to be enabled. Ensure that the [ADC_EN] bit is set to 1 if
OV and UV protections are needed.
7.3.1.2.2 Reduced Test Time
A special debug and test configuration bit is provided in the SYS_CTRL2 register, called [DELAY_DIS].
Setting [DELAY_DIS] bypasses the OV/UV protection fault timers and allows a fault condition to be
registered within 200 ms after application of such a fault condition.
7.3.1.3
Control Subsystem
7.3.1.3.1 FET Driving (CHG AND DSG)
Each bq769x0 device provides two low-side FET drivers, CHG and DSG, which control NCH power FETs
or may be used as a signal to enable various other circuits such as a high-side NCH charge pump circuit.
Both DSG and CHG drivers have a fast pull-up to nominally 12 V when enabled. DSG uses a fast pulldown to VSS when disabled, while CHG utilizes a high impedance (nominally 1 MΩ) pull-down path when
disabled.
An additional internal clamp circuit ensures that the CHG pin does not exceed a maximum of 20 V.
DSG
CHG
Q3
Q3 is a low-cost PCH FET and is used to keep CHG away
from any voltages below VSS. When CHG is not being
pulled high, PACK± being pulled below VSS will not be
seen by CHG as Q2 does not turn on. Q3 also allows R2 to
keep Q1 OFF, since all voltages below this FET can
"follow" PACK± as it goes below VSS.
R1 drops the voltage when PACK± is pulled high and
This diode allows CHG
to pull the Q1 gate high.
R1 limits the current going into the CHG pin. Since CHG
(1M) clamps at ~ 18 V, R1 will limit current to approximately
(V(PACK±) - 18) / R1.
R2
(1M)
R2
Q2
BAT±
Q1
This zener clamp may
be needed to prevent
Q1 from turning on
too quickly (optional).
PACK t
R2 clamps Q1 when
CHG is turned off.
Rsns
Figure 7-3. CHG and DSG FET Circuit
The power path for the CHG and DSG pull-up circuit originates from the REGSRC pin, instead of BAT.
To enable the CHG fet, set the [CHG_ON] register bit to 1; to disable, set [CHG_ON] = 0. The discharge
FET may be similarly controlled via the [DSG_ON] register bit.
Certain fault conditions or power state transitions will clear the state of the CHG/DSG FET controls.
Table 7-1 shows what action, if any, to take to [CHG_ON] and [DSG_ON] in response to various system
events:
Table 7-1. CHG, DSG Response Under Various System Events
26
Detailed Description
EVENT
[CHG_ON]
OV Fault
Set to 0
[DSG_ON]
—
UV Fault
—
Set to 0
OCD Fault
—
Set to 0
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Table 7-1. CHG, DSG Response Under Various System Events (continued)
EVENT
[CHG_ON]
[DSG_ON]
SCD Fault
—
Set to 0
ALERT Override
Set to 0
Set to 0
DEVICE_XREADY is set
Set to 0
Set to 0
Enter SHIP mode from NORMAL
Set to 0
Set to 0
NOTE
All protection recovery must be initiated by the host microcontroller. In order to resume FET
operation after a fault condition has occurred, the host microcontroller must first clear the
corresponding status bit in the SYS_STAT register, which will clear the ALERT pin, and then
manually re-enable the CHG and/or DSG bit. Certain faults, such as OV or UV, may
immediately re-toggle if such a condition still persists. Refer to Table 7-3 for details on
clearing status bits.
There are no conditions under which the bq769x0 automatically sets either [CHG_ON] or [DSG_ON] to 1.
7.3.1.3.2 Load Detection
A load detection circuit is present on the CHG pin and activated whenever the CHG FET is disabled
([CHG_ON] = 0). This circuit detects if the CHG pin is externally pulled high when the high impedance
(approximately 1 MΩ) pull-down path should actually be holding the CHG pin to VSS, and is useful for
determining if the PACK– pin (outside of the AFE) is being held at a high voltage—for example, if the load
is present while the power FETs are off. The state of the load detection circuit is read from the
[LOAD_PRESENT] bit of the SYS_CTRL1 register.
After an OCD or SCD fault has occurred, the DSG FET will be disabled ([DSG_ON] cleared), and the
CHG FET must similarly be explicitly disabled to activate the load detection circuit. The host
microcontroller may periodically poll the [LOAD_PRESENT] bit to determine the state of the PACK– pin
and determine when the load is removed ([LOAD_PRESENT] = 0).
7.3.1.3.3 Cell Balancing
Both internal and external passive cell balancing options are fully supported by the bq76920, while
external cell balancing is recommended for bq76930 and bq76940. It is left to the host controller to
determine the exact balancing algorithm to be used in any given system. Each bq769x0 device provides
the cell voltages and balancing drivers to enable this. If using the internal cell balance drivers, up to 50 mA
may be balanced per cell. If using external cell balancing, much higher balancing currents may be
employed.
To activate a particular cell balancing channel, simply set the corresponding bit for that cell in the
CELLBAL1, CELLBAL2, or CELLBAL3 register. For example, VC1–VC0 is enabled by setting [CB1], while
VC12–VC11 is set via [CB12].
Multiple cells may be simultaneously balanced. It is left to the user’s discretion to determine the ideal
number of cells to concurrently balance. Adjacent cells should not be balanced simultaneously. This may
cause cell pins to exceed their absolute maximum conditions and is also not recommended for external
balancing implementations. Additionally, if internal balancing is used, care should be taken to avoid
exceeding package power dissipation ratings.
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NOTE
The host controller must ensure that no two adjacent cells are balanced simultaneously
within each set of the following:
• VC1–VC5
• VC6–VC10
• VC11–VC15
The total duty cycle devoted to balancing is approximately 70% per 250 ms. This is because a portion of
the 250 ms is allotted for normal cell voltage measurements via the ADC.
If [ADC_EN] =1, OV and UV protections are not affected by cell balancing, since the cell balancing is
temporarily suspended for a small slice of time every 250 ms during which the cell voltage readings are
taken. This ensures that the OV and UV protections do not accidentally trigger, or miss an actual OV/UV
condition on the cells while balancing is enabled.
NOTE
All cell balancing control bits in CELLBAL1, CELLBAL2, and CELLBAL3 are automatically
cleared under the following events, and must be explicitly re-written by the host
microcontroller following clearing of the event:
• DEVICE_XREADY is set
• Enters NORMAL mode from SHIP mode
7.3.1.3.4 Alert
The ALERT pin serves as an active high digital interrupt signal that can be connected to a GPIO port of
the host microcontroller. This signal is an OR of all bits in the SYS_STAT register.
In order to clear the ALERT signal, the source bit in the SYS_STAT register must first be cleared by
writing a “1” to that bit. This will cause an automatic clear of the ALERT pin once all bits are cleared.
The ALERT pin may also be driven by an external source; for example, the pack may include a secondary
overvoltage protector IC. When the ALERT pin is forced high externally while low, the device will
recognize this as an OVRD_ALERT fault and set the [OVRD_ALERT] bit. This triggers automatic disabling
of both CHG and DSG FET drivers. The device cannot recognize the ALERT signal input high when it is
already forcing the ALERT signal high from another condition.
The ALERT pin has no internal debounce support so care should be taken to protect the pin from noise or
other parasitic transients.
NOTE
It is highly recommended to place an external 500 kΩ–1 MΩ pull-down resistor from ALERT
to VSS as close to the IC as possible. Additional recommendations are:
a) To keep all traces between the IC and components connected to the ALERT pin very
short.
b) To include a guard ring around the components connected to the ALERT pin and the
pin itself.
7.3.1.3.5 Output LDO
An adjustable output voltage regulator LDO is provided as a simple way to provide power to additional
components in the battery pack, such as the host microcontroller or LEDs. The LDO is configured in
EEPROM by TI during the production test process, and can support 2.5-V or 3.3-V options.
28
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A cascode small-signal FET must be added in the external path between BAT and REGSRC with the
bq76930 and bq76940. This helps drop most of the power dissipation outside of the package and cuts
down on package power dissipation.
7.3.1.4
Communications Subsystem
The AFE implements a standard 100-kHz I2C interface and acts as a slave device. The I2C device
address is 7-bits and is factory programmed. Consult the Device Comparison Table (Section 4) of this
datasheet for more information.
A write transaction is shown in Figure 7-4. Block writes are allowed by sending additional data bytes
before the Stop. The I2C block will auto-increment the register address after each data byte.
When enabled, the CRC is calculated as follows:
• In a single-byte write transaction, the CRC is calculated over the slave address, register address, and
data.
• In a block write transaction, the CRC for the first data byte is calculated over the slave address,
register address, and data. The CRC for subsequent data bytes is calculated over the data byte only.
The CRC polynomial is x8 + x2 + x + 1, and the initial value is 0.
When the slave detects a bad CRC, the I2C slave will NACK the CRC, which causes the I2C slave to go to
an idle state.
SCL
A6 A5
SDA
Start
... A0
R/W ACK
Slave Address
R7 R6
... R0
ACK
D7 D6
Register
Address
... D0
C7 C6
ACK
... C0
ACK
CRC
(optional)
Data
Stop
Figure 7-4. I2C Write
Figure 7-5 shows a read transaction using a Repeated Start.
SCL
A6 A5
SDA
Start
... A0
R/W ACK
Slave Address
R7 R6
... R0
ACK
A6 A5
Register
Address
... A0
R/W ACK
Slave Address
Repeated
Start
D7 D6
... D0
ACK
Slave
Drives Data
C7 C6
... C0
NACK
Slave
Stop
Drives CRC
(optional)
Master
Drives NACK
Figure 7-5. I2C Read with Repeated Start
Figure 7-6 shows a read transaction where a Repeated Start is not used, for example if not available in
hardware. For a block read, the master ACK’s each data byte except the last and continues to clock the
interface. The I2C block will auto-increment the register address after each data byte.
When enabled, the CRC for a read transaction is calculated as follows:
• In a single-byte read transaction, the CRC is calculated after the second start and uses the slave
address and data byte.
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In a block read transaction, the CRC for the first data byte is calculated after the second start and uses
the slave address and data byte. The CRC for subsequent data bytes is calculated over the data byte
only.
The CRC polynomial is x8 + x2 + x + 1, and the initial value is 0.
When the master detects a bad CRC, the I2C master will NACK the CRC, which causes the I2C slave to
go to an idle state.
SCL
A6 A5
SDA
Start
... A0
R/W ACK
Slave Address
R7 R6
... R0
Register
Address
A6 A5
ACK
Stop Start
D7 D6
... A0
R/W ACK
Slave Address
... D0
ACK
C7 C6
Slave
Drives Data
... C0
NACK
Slave
Stop
Drives CRC
(optional)
Master
Drives NACK
Figure 7-6. I2C Read Without Repeated Start
7.4
Device Functional Modes
Each bq769x0 device supports the following modes of operation.
Table 7-2. Supported Power Modes
Mode
Description
NORMAL
Fully operational state. Both ADC and CC may be on, or disabled by host microcontroller.
OV and UV protection enabled if ADC is on. OCD and SCD enabled. ADC and CC may be
disabled to reduce power consumption, and CC may be operated in a “1-SHOT” mode for
flexible power savings.
SHIP
7.4.1
Lowest possible power state, intended for pack assembly and/or long term pack storage.
Must see a BOOT signal (> 1 VBOOT) on TS1 pin to boot from SHIP → NORMAL. Note
that the device always enters SHIP mode upon POR.
NORMAL Mode
NORMAL mode represents the fully operational mode where all blocks are enabled and the device sees
its highest current consumption. In this mode, certain blocks/functions may be disabled to save
power—these include the ADC and CC. OV and UV are running continuously as long as the ADC is
enabled. The OCD and SCD comparators may not be disabled in this mode.
Transitioning from NORMAL to SHIP mode is also initiated by the host, and requires consecutive writes to
two bits in the SYS_CTRL1 register.
7.4.2
SHIP Mode
SHIP mode is the basic and lowest power mode that bq769x0 supports. SHIP mode is automatically
entered during initial pack assembly and after every POR event. When the device is in NORMAL mode, it
may enter SHIP by the host controller via a specific sequence of I2C commands.
In SHIP mode, only a minimum of blocks are turned on, including the VSTUP power supply and primal
boot detector. Waking from SHIP mode to NORMAL mode requires pulling the TS1 pin greater than
VBOOT, which triggers the device boot-up sequence.
30
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To enter SHIP mode from NORMAL mode, the [SHUT_A] and [SHUT_B] bits in the SYS_CTRL1 register
must be written with specific patterns across two consecutive writes:
• Write #1: [SHUT_A] = 0, [SHUT_B] = 1
• Write #2: [SHUT_A] = 1, [SHUT_B] = 0
Note that [SHUT_A] and [SHUT_B] should each be in a 0 state prior to executing the shutdown command
above. If this specific sequence is entered into the device, the device transitions into SHIP mode. If any
other sequence is written to the [SHUT_A] and [SHUT_B] bits or if either of the two patterns is not
correctly entered, the device will not enter SHIP mode.
CAUTION
DO NOT OPERATE THE DEVICE BELOW POR. When designing with the
bq76940, the intermediate voltages (BAT–VC10x), (VC10x–VC5x), and
(VC5x–VSS) must each never fall below VSHUT. When this occurs, a full device
reset must be initiated by powering down all three intermediate voltages
(BAT–VC10x), (VC10x–VC5x), and (VC5x–VSS) below VSHUT and rebooting by
applying the appropriate VBOOT signal to the TS1 pin. When designing with
the bq76930, the intermediate voltages (BAT–VC5x) and (VC5x–VSS) must
each never fall below VSHUT. If this occurs, a full device reset must be initiated
by powering down both intermediate voltages (BAT–VC5x) and (VC5x–VSS)
below VSHUT and rebooting by applying the appropriate VBOOT signal to the
TS1 pin.
The device will also enter SHIP mode during a POR event; however, this is not a recommended method
of SHIP mode entry. If any of the supply-side voltages below fall below VSHUT and then back up above
VPORA, the device defaults into the SHIP mode state. This is similar to an initial pack assembly condition.
In order to exit SHIP mode into NORMAL mode, the device must follow the standard boot sequence by
applying a voltage greater than the VBOOT threshold on the TS1 pin.
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7.5
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Register Maps
Name
Addr
D7
D6
D5
D4
D3
D2
D1
D0
SYS_STAT
0x00
CC_READY
RSVD
DEVICE_
XREADY
OVRD_
ALERT
UV
OV
SCD
OCD
SHUT_A
SHUT_B
DSG_ON
CHG_ON
CELLBAL1
0x01
RSVD
RSVD
RSVD
CB<5:1>
CELLBAL2 (1)
0x02
RSVD
RSVD
RSVD
CB<10:6>
CELLBAL3 (2)
0x03
RSVD
RSVD
RSVD
SYS_CTRL1
0x04
LOAD_
PRESENT
RSVD
RSVD
SYS_CTRL2
0x05
DELAY_DIS
CC_EN
CC_
ONESHOT
PROTECT1
0x06
RSNS
RSVD
PROTECT2
0x07
RSVD
PROTECT3
0x08
OV_TRIP
0x09
UV_TRIP
0x0A
CC_CFG
0x0B
RSVD
RSVD
VC1_HI
0x0C
RSVD
RSVD
VC1_LO
0x0D
VC2_HI
0x0E
VC2_LO
0x0F
VC3_HI
0x10
VC3_LO
0x11
VC4_HI
0x12
VC4_LO
0x13
VC5_HI
0x14
VC5_LO
0x15
VC6_HI (1)
0x16
(1)
0x17
VC7_HI (1)
0x18
VC7_LO (1)
0x19
VC8_HI (1)
0x1A
VC8_LO (1)
0x1B
VC9_HI (1)
0x1C
VC9_LO (1)
0x1D
VC10_HI (1)
0x1E
VC10_LO (1)
0x1F
VC11_HI (2)
0x20
VC11_LO (2)
0x21
VC12_HI (2)
0x22
VC12_LO (2)
0x23
VC13_HI (2)
0x24
VC13_LO (2)
0x25
VC6_LO
VC14_HI (2)
0x26
VC14_LO (2)
0x27
CB<15:11>
ADC_EN
RSVD
TEMP_SEL
RSVD
SCD_DELAY
OCD_THRESH
OV_DELAY
RSVD
OV_THRESH
UV_THRESH
Must be programmed to 0x19
<13:8>
<7:0>
RSVD
RSVD
<13:8>
<7:0>
RSVD
RSVD
<13:8>
<7:0>
RSVD
RSVD
<13:8>
<7:0>
RSVD
RSVD
<13:8>
<7:0>
RSVD
RSVD
RSVD
RSVD
<13:8>
<7:0>
<13:8>
<7:0>
RSVD
RSVD
<13:8>
<7:0>
RSVD
RSVD
<13:8>
<7:0>
RSVD
RSVD
<13:8>
<7:0>
RSVD
RSVD
<13:8>
<7:0>
RSVD
RSVD
<13:8>
<7:0>
RSVD
RSVD
<13:8>
<7:0>
RSVD
RSVD
<13:8>
<7:0>
VC15_HI (2)
0x28
VC15_LO (2)
0x29
<7:0>
BAT_HI
0x2A
<15:8>
BAT_LO
0x2B
TS1_HI
0x2C
TS1_LO
0x2D
TS2_HI (1)
0x2E
TS2_LO (1)
0x2F
(1)
(2)
32
SCD_THRESH
OCD_DELAY
UV_DELAY
RSVD
RSVD
RSVD
<13:8>
<7:0>
RSVD
RSVD
<13:8>
<7:0>
RSVD
RSVD
<13:8>
<7:0>
These registers are only valid for bq76930 and bq76940.
These registers are only valid for bq76940.
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Name
Addr
D7
D6
TS3_HI (2)
0x30
RSVD
RSVD
TS3_LO (2)
0x31
<7:0>
CC_HI
0x32
<15:8>
CC_LO
0x33
ADCGAIN1
0x50
ADCOFFSET
0x51
ADCGAIN2
0x59
7.5.1
D5
D4
D3
D2
D1
D0
<13:8>
<7:0>
RSVD
ADCGAIN<4:3>
RSVD
ADCOFFSET<7:0>
ADCGAIN<2:0>
RSVD
Register Details
Table 7-3. SYS_STAT (0x00)
BIT
7
6
5
4
3
2
1
0
NAME
CC_READY
RSVD
DEVICE_
XREADY
OVRD_
ALERT
UV
OV
SCD
OCD
RESET
0
0
0
0
0
0
0
0
ACCESS
RW
RW
RW
RW
RW
RW
RW
RW
NOTE
Bits in SYS_STAT may be cleared by writing a "1" to the corresponding bit.
Writing a "0" does not change the state of the corresponding bit.
CC_READY (Bit 7): Indicates that a fresh coulomb counter reading is available. Note that if this bit is not
cleared between two adjacent CC readings becoming available, the bit remains latched to 1. This bit may
only be cleared (and not set) by the host.
0 = Fresh CC reading not yet available or bit is cleared by host microcontroller.
1 = Fresh CC reading is available. Remains latched high until cleared by host.
RSVD (Bit 6): Reserved. Do not use.
DEVICE_XREADY (Bit 5): Internal chip fault indicator. When this bit is set to 1, it should be cleared by
the host. May be set due to excessive system transients. This bit may only be cleared (and not set) by
the host.
0 = Device is OK.
1 = Internal chip fault detected, recommend that host microcontroller clear this bit after waiting a
few seconds. Remains latched high until cleared by the host.
OVRD_ALERT (Bit 4): External pull-up on the ALERT pin indicator. Only active when ALERT pin is not
already being driven high by the AFE itself.
0 = No external override detected
1 = External override detected. Remains latched high until cleared by the host.
UV (Bit 3): Undervoltage fault event indicator.
0 = No UV fault is detected.
1 = UV fault is detected. Remains latched high until cleared by the host.
OV (Bit 2): Overvoltage fault event indicator.
0 = No OV fault is detected.
1 = OV fault is detected. Remains latched high until cleared by the host.
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SCD (Bit 1): Short circuit in discharge fault event indicator.
0 = No SCD fault is detected.
1 = SCD fault is detected. Remains latched high until cleared by the host.
OCD (Bit 0): Over current in discharge fault event indicator.
0 = No OCD fault is detected.
1 = OCD fault is detected. Remains latched high until cleared by the host.
Table 7-4. CELLBAL1 (0x01) for bq76920, bq76930, and bq76940
BIT
7
6
5
4
3
2
1
0
NAME
—
—
—
CB5
CB4
CB3
CB2
CB1
RESET
0
0
0
0
0
0
0
0
ACCESS
R
R
R
RW
RW
RW
RW
RW
CBx (Bits 4–0):
0 = Cell balancing on Cell “x” is disabled.
1 = Cell balancing on Cell “x” is enabled.
Table 7-5. CELLBAL2 (0x02) for bq76930 and bq76940
BIT
7
6
5
4
3
2
1
0
NAME
—
—
—
CB10
CB9
CB8
CB7
CB6
RESET
0
0
0
0
0
0
0
0
ACCESS
R
R
R
RW
RW
RW
RW
RW
CBx (Bits 4–0):
0 = Cell balancing on Cell “x” is disabled.
1 = Cell balancing on Cell “x” is enabled.
Table 7-6. CELLBAL3 (0x03) for bq76940
BIT
7
6
5
4
3
2
1
0
NAME
—
—
—
CB15
CB14
CB13
CB12
CB11
RESET
0
0
0
0
0
0
0
0
ACCESS
R
R
R
RW
RW
RW
RW
RW
CBx (Bits 4–0):
0 = Cell balancing on Cell “x” is disabled.
1 = Cell balancing on Cell “x” is enabled.
Table 7-7. SYS_CTRL1 (0x04)
34
BIT
7
6
5
4
3
2
1
0
NAME
LOAD_
PRESENT
—
—
ADC_EN
TEMP_SEL
RSVD
SHUT_A
SHUT_B
RESET
0
0
0
0
0
0
0
0
ACCESS
R
R
R
RW
RW
RW
RW
RW
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LOAD_PRESENT (Bit 7): Valid only when [CHG_ON] = 0. Is high if CHG pin is detected to exceed
VLOAD_DETECT while CHG_ON = 0, which suggests that external load is present. Note this bit is readonly and automatically clears when load is removed.
0 = CHG pin < VLOAD_DETECT or [CHG_ON] = 1.
1 = CHG pin >VLOAD_DETECT, while [CHG_ON] = 0.
ADC_EN (Bit 4): ADC enable command
0 = Disable voltage and temperature ADC readings (also disables OV protection)
1 = Enable voltage and temperature ADC readings (also enables OV protection)
TEMP_SEL (Bit 3): TSx_HI and TSx_LO temperature source
0 = Store internal die temperature voltage reading in TSx_HI and TSx_LO
1 = Store thermistor reading in TSx_HI and TSx_LO (all thermistor ports)
RSVD (Bit 2): Reserved, do not set to 1.
SHUT_A, SHUT_B (Bits 1–0): Shutdown command from host microcontroller. Must be written in a
specific sequence, shown below:
Starting from: [SHUT_A] = 0, [SHUT_B] = 0
Write #1: [SHUT_A] = 0, [SHUT_B] = 1
Write #2: [SHUT_A] = 1, [SHUT_B] = 0
Other writes cause the command to be ignored.
Table 7-8. SYS_CTRL2 (0x05)
BIT
7
6
5
4
3
2
1
0
NAME
DELAY_DIS
CC_EN
CC_
ONESHOT
RSVD
RSVD
RSVD
DSG_ON
CHG_ON
RESET
0
0
0
0
0
0
0
0
ACCESS
RW
RW
RW
RW
RW
RW
RW
RW
DELAY_DIS (Bit 7): Disable OV, UV, OCD, and SCD delays for faster customer production testing.
0 = Normal delay settings
1 = OV, UV, OCD, and SCD delay circuit is bypassed, creating zero delay (approximately
250 ms).
CC_EN (Bit 6): Coulomb counter continuous operation enable command. If set high, [CC_ONESHOT] bit
is ignored.
0 = Disable CC continuous readings
1 = Enable CC continuous readings and ignore [CC_ONESHOT] state
CC_ONESHOT (Bit 5): Coulomb counter single 250-ms reading trigger command. If set to 1, the
coulomb counter will be activated for a single 250-ms reading, and then turned back off.
[CC_ONESHOT] will also be cleared at the conclusion of this reading, while [CC_READY] bit will be set
to 1.
0 = No action
1 = Enable single CC reading (only valid if [CC_EN] = 0), and [CC_READY] = 0)
RSVD (Bit 4–2): Reserved. Do not use.
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DSG_ON (Bit 1): Discharge FET driver (low side NCH) or discharge signal control
0 = DSG is off.
1 = DSG is on.
CHG_ON (Bit 0): Discharge FET driver (low side NCH) or discharge signal control
0 = CHG is off.
1 = CHG is on.
Table 7-9. PROTECT1 (0x06)
BIT
7
6
5
4
3
2
1
0
NAME
RSNS
—
RSVD
SCD_D1
SCD_D0
SCD_T2
SCD_T1
SCD_T0
RESET
0
0
0
0
0
0
0
0
ACCESS
RW
R
RW
RW
RW
RW
RW
RW
RSNS (Bit 7): Allows for doubling the OCD and SCD thresholds simultaneously
0 = OCD and SCD thresholds at lower input range
1 = OCD and SCD thresholds at upper input range
RSVD (Bit 5): Reserved, do not set to 1.
SCD_D1:0 (Bits 4–3):
Short circuit in discharge delay setting. A 400-µs setting is recommended only in systems using
maximum cell measurement input resistance, Rc, of 1 kΩ (which corresponds to minimum internal cell
balancing current or external cell balancing configuration).
Code
(in µs)
0x0
70
0x1
100
0x2
200
0x3
400
SCD_T2:0 (Bits 2–0): Short circuit in discharge threshold setting
Code
RSNS = 1 (in mV)
RSNS = 0 (in mV)
0x0
44
22
0x1
67
33
0x2
89
44
0x3
111
56
0x4
133
67
0x5
155
78
0x6
178
89
0x7
200
100
Table 7-10. PROTECT2 (0x07)
36
BIT
7
6
5
4
3
2
1
0
OCD_T0
NAME
—
OCD_D2
OCD_D1
OCD_D0
OCD_T3
OCD_T2
OCD_T1
RESET
0
0
0
0
0
0
0
0
ACCESS
R
RW
RW
RW
RW
RW
RW
RW
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SLUSBK2F – OCTOBER 2013 – REVISED NOVEMBER 2015
OCD_D2:0 (Bits 6–4): Overcurrent in discharge delay setting
Code
(in ms)
0x0
8
0x1
20
0x2
40
0x3
80
0x4
160
0x5
320
0x6
640
0x7
1280
OCD_T3:0 (Bits 3–0): Overcurrent in discharge threshold setting.
Code
RSNS = 1 (in mV)
0x0
17
(RSNS = 0 (in mV)
8
0x1
22
11
0x2
28
14
0x3
33
17
0x4
39
19
0x5
44
22
0x6
50
25
0x7
56
28
0x8
61
31
0x9
67
33
0xA
72
36
0xB
78
39
0xC
83
42
0xD
89
44
0xE
94
47
0xF
100
50
Table 7-11. PROTECT3 (0x08)
BIT
7
6
5
4
3
2
1
0
RSVD
NAME
UV_D1
UV_D0
OV_D1
OV_D0
RSVD
RSVD
RSVD
RESET
0
0
0
0
0
0
0
0
ACCESS
RW
RW
RW
RW
RW
RW
RW
RW
UV_D1:0 (Bits 7–6): Undervoltage delay setting
Code
(in s)
0x0
1
0x1
4
0x2
8
0x3
16
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OV_D1:0 (Bits 5–4): Overvoltage delay setting
Code
(in s)
0x0
1
0x1
2
0x2
4
0x3
8
RSVD (Bits 3–0): These bits are for TI internal debug use only and must be configured to the default
settings indicated.
Table 7-12. OV_TRIP (0x09)
BIT
7
6
5
4
3
2
1
0
NAME
OV_T7
OV_T6
OV_T5
OV_T4
OV_T3
OV_T2
OV_T1
OV_T0
RESET
1
0
1
0
1
1
0
0
ACCESS
RW
RW
RW
RW
RW
RW
RW
RW
OV_T7:0 (Bits 7–0): Middle 8 bits of the direct ADC mapping of the desired OV protection threshold,
with upper 2 MSB set to 10 and lower 2 LSB set to 1000. The equivalent OV threshold is mapped to:
10-OV_T<7:0>1000.
By default, OV_TRIP is configured to a 0xAC setting.
Note that OV_TRIP is based on the ADC voltage, which requires back-calculation using the GAIN and
OFFSET values stored in ADCGAIN<4:0>and ADCOFFSET<7:0>.
Table 7-13. UV_TRIP (0x0A)
BIT
7
6
5
4
3
2
1
0
NAME
UV_T7
UV_T6
UV_T5
UV_T4
UV_T3
UV_T2
UV_T1
UV_T0
RESET
1
0
0
1
0
1
1
1
ACCESS
RW
RW
RW
RW
RW
RW
RW
RW
UV_T7:0 (Bits 7–0): Middle 8 bits of the direct ADC mapping of the desired UV protection threshold, with
upper 2 MSB set to 01 and lower 4 LSB set to 0000. In other words, the equivalent OV threshold is
mapped to: 01-UV_T<7:0>–0000.
By default, UV_TRIP is configured to a 0x97 setting. .
Note that UV_TRIP is based on the ADC voltage, which requires back-calculation using the GAIN and
OFFSET values stored in ADCGAIN<4:0>and ADCOFFSET<7:0>.
Table 7-14. CC_CFG REGISTER (0x0B)
38
BIT
7
6
5
4
3
2
1
0
NAME
—
—
CC_CFG5
CC_CFG4
CC_CFG3
CC_CFG2
CC_CFG1
CC_CFG0
RESET
0
0
0
0
0
0
0
0
ACCESS
R
R
RW
RW
RW
RW
RW
RW
Detailed Description
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CC_CFG5:0 (Bits 5–0): For optimal performance, these bits should be programmed to 0x19 upon device
startup.
7.5.2
Read-Only Registers
Table 7-15. CELL VOLTAGE REGISTERS
VC1_HI, _LO (0x0C–0x0D), VC2_HI, _LO (0x0E–0x0F), VC3_HI, _LO (0x10–0x11), VC4_HI, _LO (0x12–0x13), VC5_HI, _LO
(0x14–0x15) / bq76930, bq76940: VC6_HI, _LO (0x16–0x17), VC7_HI, _LO (0x18–0x19), VC8_HI, _LO (0x1A–0x1B), VC9_HI, _LO
(0x1C–0x1D), VC10_HI, _LO (0x1E–0x1F) / bq76940: VC11_HI, _LO (0x20–0x21), VC12_HI, _LO (0x22–0x23), VC13_HI, _LO
(0x24–0x25), VC14_HI, _LO (0x26–0x27), VC15_HI, _LO (0x28–0x29)
BIT
7
6
5
4
3
2
1
0
NAME
—
—
D13
D12
D11
D10
D9
D8
RESET
0
0
0
0
0
0
0
0
NAME
D7
D6
D5
D4
D3
D2
D1
D0
RESET
0
0
0
0
0
0
0
0
D11:8 (Bits 3–0): Cell “x” ADC reading, upper 6 MSB. Always returned as an atomic value if both high
and low registers are read in the same transaction (using address auto-increment).
D7:0 (Bits 7–0): Cell ”x” ADC reading, lower 8 LSB.
Table 7-16. BAT_HI (0x2A) and BAT_LO (0x2B)
BIT
7
6
5
4
3
2
1
0
NAME
D15
D14
D13
D12
D11
D10
D9
D8
RESET
0
0
0
0
0
0
0
0
NAME
D7
D6
D5
D4
D3
D2
D1
D0
RESET
0
0
0
0
0
0
0
0
D15:8 (Bits 7–0): BAT calculation based on adding up Cells 1–15, upper 8 MSB. Always returned as an
atomic value if both high and low registers are read in the same transaction (using address autoincrement).
D7:0 (Bits 7–0): BAT calculation based on adding up Cells 1–15, lower 8 LSB
Table 7-17. TS1_HI (0x2C) and TS1_LO (0x2D)
BIT
7
6
5
4
3
2
1
0
NAME
—
—
D13
D12
D11
D10
D9
D8
RESET
0
0
0
0
0
0
0
0
NAME
D7
D6
D5
D4
D3
D2
D1
D0
RESET
0
0
0
0
0
0
0
0
D11:8 (Bits 3–0): TS1 or DIETEMP ADC reading, upper 6 MSB. Always returned as an atomic value if
both high and low registers are read in the same transaction (using address auto-increment).
D7:0 (Bits 7–0): TS1 or DIETEMP ADC reading, lower 8 LSB
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Table 7-18. TS2_HI (0x2E) and TS2_LO (0x2F)
BIT
7
6
5
4
3
2
1
0
NAME
—
—
D13
D12
D11
D10
D9
D8
RESET
0
0
0
0
0
0
0
0
NAME
D7
D6
D5
D4
D3
D2
D1
D0
RESET
0
0
0
0
0
0
0
0
D11:8 (Bits 3–0): TS2 ADC reading, upper 6 MSB. Always returned as an atomic value if both high and
low registers are read in the same transaction (using address auto-increment).
D7:0 (Bits 7–0): TS2 ADC reading, lower 8 LSB
Table 7-19. TS3_HI (0x30) and TS3_LO (0x31)
BIT
7
6
5
4
3
2
1
0
NAME
—
—
D13
D12
D11
D10
D9
D8
RESET
0
0
0
0
0
0
0
0
NAME
D7
D6
D5
D4
D3
D2
D1
D0
RESET
0
0
0
0
0
0
0
0
D11:8 (Bits 3–0): TS3 ADC reading, upper 6 MSB. Always returned as an atomic value if both high and
low registers are read in the same transaction (using address auto-increment).
D7:0 (Bits 7–0): TS3 ADC reading, lower 8 LSB
Table 7-20. CC_HI (0x32) and CC_LO (0x33)
BIT
7
6
5
4
3
2
1
0
NAME
CC15
CC14
CC13
CC12
CC11
CC10
CC9
CC8
RESET
0
0
0
0
0
0
0
0
NAME
CC7
CC6
CC5
CC4
CC3
CC2
CC1
CC0
RESET
0
0
0
0
0
0
0
0
CC15:8 (Bits 7–0): Coulomb counter upper 8 MSB. Always returned as an atomic value if both high and
low registers are read in the same transaction (using address auto-increment).
CC7:0 (Bits 7–0): Coulomb counter lower 8 LSB
Table 7-21. ADCGAIN1 (0x50)
BIT
7
6
5
4
3
2
1
0
NAME
—
—
—
—
ADCGAIN4
ADCGAIN3
—
—
RESET
—
—
—
—
—
—
—
—
ACCESS
R
R
R
R
R
R
R
R
Table 7-22. ADCGAIN2 (0x59)
BIT
7
6
5
4
3
2
1
0
NAME
ADCGAIN2
ADCGAIN1
ADCGAIN0
—
—
—
—
—
RESET
—
—
—
—
—
—
—
—
ACCESS
R
R
R
R
R
R
R
R
ADCGAIN4:3 (Bits 3–2, address 0x50):
ADC GAIN
offset upper 2 MSB
40
Detailed Description
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ADCGAIN2:0 (Bits 7–5, address 0x59):
ADC GAIN offset lower 3 LSB
ADCGAIN<4:0> is a production-trimmed value for the ADC transfer function, in
units of µV/LSB. The range is 365 µV/LSB to 396 µV/LSB, in steps of 1 µV/LSB,
and may be calculated as follows:
GAIN = 365 µV/LSB + (ADCGAIN<4:0>in decimal) × (1 µV/LSB)
Alternately, a conversion table is provided below:
ADC GAIN
Gain (µV/LSB)
ADC GAIN
Gain (µV/LSB)
0x00
365
0x10
381
0x01
366
0x11
382
0x02
367
0x12
383
0x03
368
0x13
384
0x04
369
0x14
385
0x05
370
0x15
386
0x06
371
0x16
387
0x07
372
0x17
388
0x08
373
0x18
389
0x09
374
0x19
390
0x0A
375
0x1A
391
0x0B
376
0x1B
392
0x0C
377
0x1C
393
0x0D
378
0x1D
394
0x0E
379
0x1E
395
0x0F
380
0x1F
396
Table 7-23. ADCOFFSET (0x51)
BIT
7
6
5
4
3
2
1
0
NAME
ADC
OFFSET7
ADC
OFFSET6
ADC
OFFSET5
ADC
OFFSET4
ADC
OFFSET3
ADC
OFFSET2
ADC
OFFSET1
ADC
OFFSET0
RESET
—
—
—
—
—
—
—
—
ACCESS
R
R
R
R
R
R
R
R
ADCOFFSET7:0 (Bits 7–0):
ADC offset, stored in 2’s complement format in mV units. Positive full-scale range
corresponds to 0x7F and negative full-scale corresponds to 0x80. The full-scale
input range is –128 mV to 127 mV, with an LSB of 1 mV.
The table below shows example offsets.
ADCOFFSET
Offset (mV)
0x00
0
0x01
1
0x7F
127
0x80
–128
0x81
–127
0xFF
–1
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8 Application and Implementation
NOTE
Information in the following application section is not part of the TI component specification,
and TI does not warrant its accuracy or completeness. TI’s customers are responsible for
determining suitability of components for their purposes. Customers should validate and test
their design implementation to confirm system functionality.
8.1
Application Information
The bq769x0 family of battery monitoring AFEs enabling cell parametric measurement and protection is a
variety of 3-series to 15-series Li-Ion/Li Polymer battery packs.
To evaluate the performance and configurations of the device users need the bq76940/bq76930/bq76920
Evaluation Software, (SLUCC539) tool to configure the internal registers for a specific battery pack and
application. The Evaluation Software tool is a graphical user-interface tool installed on a PC during
development. This can be used in conjunction with the bq76920EVM, bq76930EVM or bq76940EVM.
The bq769x0 devices are expected to be implemented in a system with a microcontroller that can perform
additional functions based on the data made collected. The bq78350 is one example of a companion to
the bq769x0 family.
8.1.1
Configuring Alternative Cell Counts
Each bq769x0 family of IC's support a variety of cell counts. The following tables provide guidance on
which device and which input pins to use, depending on the number of cells in the pack.
Table 8-1. Cell Connections for bq76920
Cell Input
3 Cells
4 Cells
5 Cells
VC5–VC4
CELL 3
CELL 4
CELL 5
VC4–VC3
short
short
CELL 4
VC3–VC2
short
CELL 3
CELL 3
VC2–VC1
CELL 2
CELL 2
CELL 2
VC1–VC0
CELL 1
CELL 1
CELL 1
Table 8-2. Cell Connections for bq76930
42
Cell Input
6 Cells
7 Cells
8 Cells
9 Cells
10 Cells
VC10–VC9
CELL 6
CELL 7
CELL 8
CELL 9
CELL 10
VC9–VC8
short
short
short
short
CELL 9
VC8–VC7
short
short
CELL 7
CELL 8
CELL 8
VC7–VC6
CELL 5
CELL 6
CELL 6
CELL 7
CELL 7
VC6–VC5b
CELL 4
CELL 5
CELL 5
CELL 6
CELL 6
VC5–VC4
CELL 3
CELL 4
CELL 4
CELL 5
CELL 5
VC4–VC3
short
short
short
CELL 4
CELL 4
VC3–VC2
short
CELL 3
CELL 3
CELL 3
CELL 3
VC2–VC1
CELL 2
CELL 2
CELL 2
CELL 2
CELL 2
VC1–VC0
CELL 1
CELL 1
CELL 1
CELL 1
CELL 1
Application and Implementation
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Table 8-3. Cell Connections for bq76940
Cell Input
9 Cells
10 Cells
11 Cells
12 Cells
13 Cells
14 Cells
15 Cells
VC15–VC14
CELL 9
CELL 10
CELL 11
CELL 12
CELL 13
CELL 14
CELL 15
VC14–VC13
short
short
short
short
short
short
CELL 14
VC13–VC12
short
short
short
CELL 11
CELL 12
CELL 13
CELL 13
VC12–VC11
CELL 8
CELL 9
CELL 10
CELL 10
CELL 11
CELL 12
CELL 12
VC11–VC10b
CELL 7
CELL 8
CELL 9
CELL 9
CELL 10
CELL 11
CELL 11
VC10–VC9
CELL 6
CELL 7
CELL 8
CELL 8
CELL 9
CELL 10
CELL 10
VC9–VC8
short
short
short
short
short
CELL 9
CELL 9
VC8–VC7
short
short
CELL 7
CELL 7
CELL 8
CELL 8
CELL 8
VC7–VC6
CELL 5
CELL 6
CELL 6
CELL 6
CELL 7
CELL 7
CELL 7
VC6–VC5b
CELL 4
CELL 5
CELL 5
CELL 5
CELL 6
CELL 6
CELL 6
VC5–VC4
CELL 3
CELL 4
CELL 4
CELL 4
CELL 5
CELL 5
CELL 5
VC4–VC3
short
short
short
short
CELL 4
CELL 4
CELL 4
VC3–VC2
short
CELL 3
CELL 3
CELL 3
CELL 3
CELL 3
CELL 3
VC2–VC1
CELL 2
CELL 2
CELL 2
CELL 2
CELL 2
CELL 2
CELL 2
VC1–VC0
CELL 1
CELL 1
CELL 1
CELL 1
CELL 1
CELL 1
CELL 1
8.2
Typical Applications
CAUTION
The external circuitries in the following schematics show minimum requirements
to ensure device robustness during cell connection to the PCB and normal
operation.
PACK +
Rf
BAT
Rc
Cc
Rc
Cc
Rc
Cc
Rc
Cc
VC5
REGSRC
VC4
REGOUT
VC3
CAP1
VC2
TS1
VC1
SCL
VC0
SDA
SRP
VSS
SRN
CHG
ALERT
DSG
10 kΩ
1 µF
1 µF
Cf
4.7 µF
10k
PUSH-BUTTON FOR BOOT
VCC
Rc
Cc
SCL
SDA
Cc
1M
Rc
0.1 µF
0.1 µF
100
Companion
Controller
GPIO
VSS
0.1 µF
100
1M
1M
Rsns
PACK–
Figure 8-1. bq76920 with bq78350 Companion Controller IC
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PACK +
Rc
Cc
Rc
Cc
Rc
Cc
Rc
Rf
VC10
Cc
Rc
Cc
VC5x
Rc
VC9
CAP2
VC8
TS2
VC7
NC
VC6
Cc
VC5b
A
Rc
Cc
Rc
Cc
Rc
Cc
Rc
Cc
Rc
Rc
BAT
Cf
10k
1 µF
NC
A
VC5x
VC5
REGSRC
VC4
REGOUT
VC3
CAP1
VC2
TS1
VC1
SCL
VC0
SDA
SRP
VSS
SRN
CHG
ALERT
DSG
Rf
10 kΩ
1µF
1µF
Cf
4.7 µF
10k
PUSH-BUTTON FOR BOOT
VCC
Cc
SCL
SDA
Cc
1M
0.1 µF
0.1 µF
100
Companion
Controller
GPIO
VSS
0.1 µF
100
1M
1M
Rsns
PACK -
Figure 8-2. bq76930 with bq78350 Companion Controller IC
44
Application and Implementation
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PACK +
Rc
Cc
Rc
Cc
Rc
Cc
Rc
Cc
Rc
Cc
VC10x
Rc
Cc
Rf
B
Rc
Cc
Rc
VC15
Cc
Rc
Cc
VC14
BAT
VC13
CAP3
VC12
TS3
VC11
NC
VC10b
Rc
Cc
Rc
Cc
VC5x
Rc
VC10x
VC9
CAP2
VC8
TS2
VC7
NC
Cc
Rc
Cc
Rc
Cc
Rc
Cc
Cf
10k
1 µF
VC5x
VC5
REGSRC
VC4
REGOUT
VC3
CAP1
VC2
TS1
VC1
SCL
VC0
SDA
SRP
VSS
SRN
CHG
ALERT
DSG
A
Rf
10 kΩ
1 µF
1 µF
Cf
4.7 µF
10k
PUSH-BUTTON FOR BOOT
VCC
Rc
Rc
B
Rf
NC
VC5b
Rc
1 µF
NC
VC10
VC6
Cc
A
Cf
10k
Cc
SCL
SDA
Cc
1M
0.1 µF
0.1 µF
100
Companion
Controller
GPIO
VSS
0.1 µF
100
1M
1M
Rsns
PACK –
Figure 8-3. bq76940 with bq78350 Companion Controller IC
8.2.1
Design Requirements
Table 8-4. bq769x0 Design Requirements
DESIGN PARAMETER
EXAMPLE VALUE at TA = 25°C
Minimum system operating voltage
24 V
Cell minimum operating voltage
3.0 V
Series Cell Count
8
Charge Voltage
33.6 V
Maximum Charge Current
3.0 A
Peak Discharge Current
10.0 A
OV Protection Threshold
4.30 V
OV Protection Delay
2s
UV Protection Threshold
2.5 V
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Table 8-4. bq769x0 Design Requirements (continued)
8.2.2
DESIGN PARAMETER
EXAMPLE VALUE at TA = 25°C
UV Protection Delay
4s
OCD Protection Threshold Max
15 A
OCD Protection Delay Time
320 ms
SCD Protection Threshold Max
25 A
SCD Protection Delay Time
100 µs
Detailed Design Procedure
To begin the design process, there are some key steps required for component selection and protection
configuration.
8.2.2.1
•
•
•
•
•
46
Step-by-Step Design Procedure
Determine the number of series cells.
– This value depends on the cell chemistry and the load requirements of the system. For example, to
support a minimum battery voltage of 24 V using Li-CO2 type cells with a cell minimum voltage of
3.0 V, there needs to be at least 8-series cells.
Select the correct bq769x0 device.
– For 8-series cells, the bq76930 is needed.
– For the correct cell connections, see Table 8-2.
Select the correct protection FETs.
– The bq76930 uses a low-side drive suitable for N-CH FETs.
– These FETs should be rated for the maximum:
• Voltage, which should be approximately 5 V (DC) 10 V (peak) per series cell: for example, 40 V.
• Current, which should be calculated based on both the maximum DC current and the maximum
transient current with some margin: for example, 30 A.
• Power Dissipation, which can be a factor of the RDS(ON) rating of the FET, the FET package,
and the PCB design: for example, 5 W, assuming 5 mΩ RDS(ON).
Select the correct sense resistor.
– The resistance value should be selected to maximize the input bandwidth use of the coulomb
counter range, CCRANGE, but not exceed the absolute maximum ratings.
• Using the normal max discharge current, RSNS = 200 mV / 10.0 A = 20 mΩ.
• However, considering ISCD of 25 A and Abs Max SRP–SRN input of –300 mV, RSNS = 300 mV
/ 25 A = 7.5 mΩ
• The maximum operating current of the system should also be considered as this should be
below the maximum OCD Threshold, which with a RSNS of 7.5 mΩ gives a max OCD current
setting of 13.3 A.
– Further tolerance analysis (value tolerance, temperature variation, and so on) and PCB design
margin should also be considered, so RSNS of 5 mΩ would be suitable with a 75-ppm temperature
coefficient and power rating of 5 W.
The bq76930 is chosen, and so the REGSRC pin needs to be powered through a source follower
circuit where the FET is used to provide current for REGSRC from the battery positive terminal while
reducing the voltage to a suitable value for the IC.
– The FET also dissipates the power resulting from the load current and dropped voltage external to
the IC and care should be taken to ensure the correct dissipation ratings are specified by the
chosen FET.
Application and Implementation
Copyright © 2013–2015, Texas Instruments Incorporated
Submit Documentation Feedback
Product Folder Links: bq76920 bq76930 bq76940
bq76920, bq76930, bq76940
www.ti.com
•
SLUSBK2F – OCTOBER 2013 – REVISED NOVEMBER 2015
Configure the Current-based protection settings through PROTECT1 and PROTECT2:
– Ideal SCD Threshold = 25 A × 5 mΩ = 125 mV.
• However, the closest options are 111 mV (0x03) and 133 mV (0x04) providing 22.2 A and 26.6
A, respectively. Both options have the RSNS bit = 1.
• 0x03 (22.2 A) will be used in this example.
– The SCD delay threshold setting for a 100 µs delay is 0x01.
– Therefore, PROTECT1 should be programmed with 0x8C.
– Ideal OCD Threshold = 15 A × 5 mΩ = 75 mV.
• However, the closest options are 72 mV (0x0A) and 78 mV (0x0B), providing 14.4 A and 15.6 A,
respectively. Both options have the RSNS bit = 1.
• 0x0A (14,4A) will be used in this example.
– The OCD delay threshold setting for a 320-ms delay is 0x05.
– Therefore, PROTECT2 should be programmed with 0x5B.
NOTE
Care should be taken when determining the setting of OV_TRIP and UV_TRIP as these are
ADC value outputs and correlation to cell voltage also requires consideration of the ADC
GAIN and ADC OFFSET registers. More specific details can be found in Section 7.3.1.2.
•
Configure the Voltage-based protection settings through OV_TRIP, UV_TRIP and PROTECT3:
– The selected OV Threshold is 4.30 V.
• Therefore, OV_TRIP should be programmed with 0xC9.
– The selected UV Threshold is 2.5 V.
• Therefore, UV_TRIP should be programmed with 0x1A.
– The selected OV Delay is 2 s and the selected UV Delay is 4 s.
• Therefore, PROTECT3 should be programmed with 0x50.
Copyright © 2013–2015, Texas Instruments Incorporated
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Product Folder Links: bq76920 bq76930 bq76940
Application and Implementation
47
bq76920, bq76930, bq76940
SLUSBK2F – OCTOBER 2013 – REVISED NOVEMBER 2015
Application Curves
0.020
VCx Error (mV)
0.0
VC1 Error
0.018
0.016
VC2 Error
±0.2
0.014
VC3 Error
±0.4
0.012
VC4 Error
0.010
VC5 Error
Offset (uV)
8.2.3
www.ti.com
0.008
0.006
±0.8
0.004
±1.0
0.002
±1.2
0.000
±1.4
±0.002
±0.004
2.00 2.30 2.60 2.90 3.20 3.50 3.80 4.10 4.40 4.70 5.00
VCx Input (V)
Application and Implementation
±1.6
±40
±15
10
35
60
Temperature (ƒC)
C001
Figure 8-4. bq76930 VCx Error Across Input Range @ 25°C
48
±0.6
85
C002
Figure 8-5. Coulomb Counter Offset
Copyright © 2013–2015, Texas Instruments Incorporated
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Product Folder Links: bq76920 bq76930 bq76940
bq76920, bq76930, bq76940
www.ti.com
SLUSBK2F – OCTOBER 2013 – REVISED NOVEMBER 2015
9 Power Supply Recommendations
The bq769x0 devices are powered through the BAT and REGSRC pins but the bq76930 and bq76940
have additional ‘Power’ pins to provide the power to the entire device in the higher cell configurations.
The use of Rf and Cf connected to the BAT pin, noted in the typical application diagrams, are required to
filter system transients from disturbing the device power supply. These components should be placed as
close as to the IC as possible.
Additionally, for the bq76930 and bq76940 there are additional requirements to ensure a stable power
supply to the device. The REGSRC pin is powered through a source follower circuit where the FET is
used to provide current for REGSRC from the battery positive terminal while reducing the voltage to a
suitable value for the IC. The FET also dissipates the power resulting from the load current and dropped
voltage external to the IC and care should be taken to ensure the correct dissipation ratings are specified
by the chosen FET.
The bq76920 does not use a FET because the battery voltage is within the REGSRC range.
Copyright © 2013–2015, Texas Instruments Incorporated
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Product Folder Links: bq76920 bq76930 bq76940
Power Supply Recommendations
49
bq76920, bq76930, bq76940
SLUSBK2F – OCTOBER 2013 – REVISED NOVEMBER 2015
www.ti.com
10 Layout
10.1 Layout Guidelines
It is strongly recommended for best measurement performance to keep high current signals from
interfering with the measurement system inputs and ground.
A second key recommendation is to ensure that the bq769x0 input filtering capacitors and power
capacitors are connected to a common ground with as little parasitic resistance between the connections
as possible.
10.2 Layout Example
Figure 10-1 shows a guideline of how to place key components compared to respective ground zones,
based on the bq76920/30/40 EVMs.
bq769x0
bq78350
Low Current Ground Plane Available Area
Key components placed here
bq78350
bq76920/30/40
Measurement Filter
Resistors and Capacitors
Ground
interconnect
BAT-
RSNS
DSG
PACK-
CHG
Key components placed here
Protection FETs
Sense Resistor
BAT+
PACK+
High Current Ground Plane Available Area
Figure 10-1. System Component Placement Layout vs. Ground Zone Guide
CAUTION
Care should be taken when placing key power pin capacitors to minimize PCB
trace impedances. These impedances could result in device resets or other
unexpected operations when the device is at peak power consumption.
Although not shown in the diagrams, this caution also applies to the resistor
and capacitor network surrounding the current sense resistor.
50
Layout
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Product Folder Links: bq76920 bq76930 bq76940
bq76920, bq76930, bq76940
www.ti.com
SLUSBK2F – OCTOBER 2013 – REVISED NOVEMBER 2015
BATTERY–
bq76920
REGSRC
REGOUT
VC1
VC0
PCB Trace impedance
VSS
SENSE
RESISTOR
Figure 10-2.
Good Layout: Input Capacitor Grounding with Low Parasitic PCB Impedance
Copyright © 2013–2015, Texas Instruments Incorporated
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Product Folder Links: bq76920 bq76930 bq76940
Layout
51
bq76920, bq76930, bq76940
SLUSBK2F – OCTOBER 2013 – REVISED NOVEMBER 2015
www.ti.com
BATTERY–
bq76920
REGSRC
REGOUT
VC1
VC0
PCB Trace impedance
VSS
SENSE
RESISTOR
Figure 10-3.
Weak Layout: Input Capacitor Grounding with High Parasitic PCB Impedance
52
Layout
Copyright © 2013–2015, Texas Instruments Incorporated
Submit Documentation Feedback
Product Folder Links: bq76920 bq76930 bq76940
bq76920, bq76930, bq76940
www.ti.com
SLUSBK2F – OCTOBER 2013 – REVISED NOVEMBER 2015
11 Device and Documentation Support
11.1 Documentation Support
11.1.1 Related Documentation
For related documentation, see the following: bq76920 Evaluation Module User 's Guide (SLVU924), and
bq76920, bq76930, bq76940 AFE FAQ (SLUUB41).
11.2 Related Links
The table below lists quick access links. Categories include technical documents, support and community
resources, tools and software, and quick access to sample or buy.
Table 11-1. Related Links
PARTS
PRODUCT FOLDER
SAMPLE & BUY
TECHNICAL
DOCUMENTS
TOOLS &
SOFTWARE
SUPPORT &
COMMUNITY
bq76920
Click here
Click here
Click here
Click here
Click here
bq76930
Click here
Click here
Click here
Click here
Click here
bq76940
Click here
Click here
Click here
Click here
Click here
11.2.1 Community Resources
The following links connect to TI community resources. Linked contents are provided "AS IS" by the
respective contributors. They do not constitute TI specifications and do not necessarily reflect TI's views;
see TI's Terms of Use.
TI E2E™ Online Community TI's Engineer-to-Engineer (E2E) Community. Created to foster
collaboration among engineers. At e2e.ti.com, you can ask questions, share knowledge,
explore ideas and help solve problems with fellow engineers.
TI Embedded Processors Wiki Texas Instruments Embedded Processors Wiki. Established to help
developers get started with Embedded Processors from Texas Instruments and to foster
innovation and growth of general knowledge about the hardware and software surrounding
these devices.
11.3 Trademarks
E2E is a trademark of Texas Instruments.
I2C is a trademark of NXP B.V. Corporation.
All other trademarks are the property of their respective owners.
11.4 Electrostatic Discharge Caution
This integrated circuit can be damaged by ESD. Texas Instruments recommends that all integrated circuits be handled with
appropriate precautions. Failure to observe proper handling and installation procedures can cause damage.
ESD damage can range from subtle performance degradation to complete device failure. Precision integrated circuits may be more
susceptible to damage because very small parametric changes could cause the device not to meet its published specifications.
11.5 Glossary
TI Glossary This glossary lists and explains terms, acronyms, and definitions.
12 Mechanical, Packaging, and Orderable Information
The following pages include mechanical, packaging, and orderable information. This information is the
most current data available for the designated devices. This data is subject to change without notice and
revision of this document. For browser-based versions of this data sheet, refer to the left-hand navigation.
Mechanical, Packaging, and Orderable Information
Submit Documentation Feedback
Product Folder Links: bq76920 bq76930 bq76940
Copyright © 2013–2015, Texas Instruments Incorporated
53
PACKAGE OPTION ADDENDUM
www.ti.com
30-Mar-2016
PACKAGING INFORMATION
Orderable Device
Status
(1)
Package Type Package Pins Package
Drawing
Qty
Eco Plan
Lead/Ball Finish
MSL Peak Temp
(2)
(6)
(3)
Op Temp (°C)
Device Marking
(4/5)
BQ7692000PW
ACTIVE
TSSOP
PW
20
70
Green (RoHS
& no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
-40 to 85
BQ7692000
BQ7692000PWR
ACTIVE
TSSOP
PW
20
2000
Green (RoHS
& no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
-40 to 85
BQ7692000
BQ7692003PW
ACTIVE
TSSOP
PW
20
70
Green (RoHS
& no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
-40 to 85
BQ7692003
BQ7692003PWR
ACTIVE
TSSOP
PW
20
2000
Green (RoHS
& no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
-40 to 85
BQ7692003
BQ7692006PW
ACTIVE
TSSOP
PW
20
70
Green (RoHS
& no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
-40 to 85
BQ7692006
BQ7692006PWR
ACTIVE
TSSOP
PW
20
2000
Green (RoHS
& no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
-40 to 85
BQ7692006
BQ7693000DBT
ACTIVE
TSSOP
DBT
30
60
Green (RoHS
& no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
-40 to 85
BQ7693000
BQ7693000DBTR
ACTIVE
TSSOP
DBT
30
2000
Green (RoHS
& no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
-40 to 85
BQ7693000
BQ7693001DBT
ACTIVE
TSSOP
DBT
30
60
Green (RoHS
& no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
-40 to 85
BQ7693001
BQ7693001DBTR
ACTIVE
TSSOP
DBT
30
2000
Green (RoHS
& no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
-40 to 85
BQ7693001
BQ7693002DBT
ACTIVE
TSSOP
DBT
30
60
Green (RoHS
& no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
-40 to 85
BQ7693002
BQ7693002DBTR
ACTIVE
TSSOP
DBT
30
2000
Green (RoHS
& no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
-40 to 85
BQ7693002
BQ7693003DBT
ACTIVE
TSSOP
DBT
30
60
Green (RoHS
& no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
-40 to 85
BQ7693003
BQ7693003DBTR
ACTIVE
TSSOP
DBT
30
2000
Green (RoHS
& no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
-40 to 85
BQ7693003
BQ7693006DBT
ACTIVE
TSSOP
DBT
30
60
Green (RoHS
& no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
-40 to 85
BQ7693006
BQ7693006DBTR
ACTIVE
TSSOP
DBT
30
2000
Green (RoHS
& no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
-40 to 85
BQ7693006
BQ7693007DBT
ACTIVE
TSSOP
DBT
30
60
Green (RoHS
& no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
-40 to 85
BQ7693007
Addendum-Page 1
Samples
PACKAGE OPTION ADDENDUM
www.ti.com
Orderable Device
30-Mar-2016
Status
(1)
Package Type Package Pins Package
Drawing
Qty
Eco Plan
Lead/Ball Finish
MSL Peak Temp
(2)
(6)
(3)
Op Temp (°C)
Device Marking
(4/5)
BQ7693007DBTR
ACTIVE
TSSOP
DBT
30
2000
Green (RoHS
& no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
-40 to 85
BQ7693007
BQ7694000DBT
ACTIVE
TSSOP
DBT
44
40
Green (RoHS
& no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
-40 to 85
BQ7694000
BQ7694000DBTR
ACTIVE
TSSOP
DBT
44
2000
Green (RoHS
& no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
-40 to 85
BQ7694000
BQ7694001DBT
ACTIVE
TSSOP
DBT
44
40
Green (RoHS
& no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
-40 to 85
BQ7694001
BQ7694001DBTR
ACTIVE
TSSOP
DBT
44
2000
Green (RoHS
& no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
-40 to 85
BQ7694001
BQ7694002DBT
ACTIVE
TSSOP
DBT
44
40
Green (RoHS
& no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
-40 to 85
BQ7694002
BQ7694002DBTR
ACTIVE
TSSOP
DBT
44
2000
Green (RoHS
& no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
-40 to 85
BQ7694002
BQ7694003DBT
ACTIVE
TSSOP
DBT
44
40
Green (RoHS
& no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
-40 to 85
BQ7694003
BQ7694003DBTR
ACTIVE
TSSOP
DBT
44
2000
Green (RoHS
& no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
-40 to 85
BQ7694003
BQ7694006DBT
ACTIVE
TSSOP
DBT
44
40
Green (RoHS
& no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
-40 to 85
BQ7694006
BQ7694006DBTR
ACTIVE
TSSOP
DBT
44
2000
Green (RoHS
& no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
-40 to 85
BQ7694006
(1)
The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2)
Eco Plan - The planned eco-friendly classification: Pb-Free (RoHS), Pb-Free (RoHS Exempt), or Green (RoHS & no Sb/Br) - please check http://www.ti.com/productcontent for the latest availability
information and additional product content details.
TBD: The Pb-Free/Green conversion plan has not been defined.
Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements for all 6 substances, including the requirement that
lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes.
Pb-Free (RoHS Exempt): This component has a RoHS exemption for either 1) lead-based flip-chip solder bumps used between the die and package, or 2) lead-based die adhesive used between
the die and leadframe. The component is otherwise considered Pb-Free (RoHS compatible) as defined above.
Addendum-Page 2
Samples
PACKAGE OPTION ADDENDUM
www.ti.com
30-Mar-2016
Green (RoHS & no Sb/Br): TI defines "Green" to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and Antimony (Sb) based flame retardants (Br or Sb do not exceed 0.1% by weight
in homogeneous material)
(3)
MSL, Peak Temp. - The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature.
(4)
There may be additional marking, which relates to the logo, the lot trace code information, or the environmental category on the device.
(5)
Multiple Device Markings will be inside parentheses. Only one Device Marking contained in parentheses and separated by a "~" will appear on a device. If a line is indented then it is a continuation
of the previous line and the two combined represent the entire Device Marking for that device.
(6)
Lead/Ball Finish - Orderable Devices may have multiple material finish options. Finish options are separated by a vertical ruled line. Lead/Ball Finish values may wrap to two lines if the finish
value exceeds the maximum column width.
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information
provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and
continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals.
TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release.
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis.
Addendum-Page 3
PACKAGE MATERIALS INFORMATION
www.ti.com
14-Nov-2014
TAPE AND REEL INFORMATION
*All dimensions are nominal
Device
Package Package Pins
Type Drawing
SPQ
Reel
Reel
A0
Diameter Width (mm)
(mm) W1 (mm)
B0
(mm)
K0
(mm)
P1
(mm)
W
Pin1
(mm) Quadrant
BQ7692000PWR
TSSOP
PW
20
2000
330.0
16.4
6.95
7.1
1.6
8.0
16.0
Q1
BQ7692003PWR
TSSOP
PW
20
2000
330.0
16.4
6.95
7.1
1.6
8.0
16.0
Q1
BQ7692006PWR
TSSOP
PW
20
2000
330.0
16.4
6.95
7.1
1.6
8.0
16.0
Q1
Pack Materials-Page 1
PACKAGE MATERIALS INFORMATION
www.ti.com
14-Nov-2014
*All dimensions are nominal
Device
Package Type
Package Drawing
Pins
SPQ
Length (mm)
Width (mm)
Height (mm)
BQ7692000PWR
TSSOP
PW
20
2000
367.0
367.0
38.0
BQ7692003PWR
TSSOP
PW
20
2000
367.0
367.0
38.0
BQ7692006PWR
TSSOP
PW
20
2000
367.0
367.0
38.0
Pack Materials-Page 2
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