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FEATURES
APPLICATIONS
DESCRIPTION
bq20z70
SLUS686A NOVEMBER 2005 REVISED JUNE 2006
SBS 1.1-COMPLIANT GAS GAUGE ENABLED WITH IMPEDANCE TRACKTM
TECHNOLOGY FOR USE WITH THE bq29330
Notebook PCs
Next Generation Patented Impedance TrackTM
Technology accurately Measures Available
Medical and Test Equipment
Charge in Li-Ion and Li-Polymer Batteries
Portable Instrumentation
Better than 1% Error Over Lifetime of the
Battery
Instant Accuracy No Learning Cycle
The
bq20z70
SBS-compliant
gas
gauge
IC,
Required
incorporating
patented
Impedance
TrackTM
technology, is designed for battery-pack or in-system
Supports the Smart Battery Specification
installation. The bq20z70 measures and maintains
SBS V1.1
an accurate record of available charge in Li-ion or
Powerful 8-Bit RISC CPU With Ultra-Low
Li-polymer
batteries
using
its
integrated
Power Modes
high-performance analog peripherals. The bq20z70
monitors
capacity
change,
battery
impedance,
Works With the TI bq29330 Analog Front-End
open-circuit voltage, and other critical parameters of
(AFE) Protection IC to Provide Complete Pack
the battery pack, and reports the information to the
Electronics Solution
system host controller over a serial-communication
Full Array of Programmable Protection
bus. It is designed to work with the bq29330 analog
Features
front-end
(AFE)
protection
IC
to
maximize
Voltage, Current and Temperature
functionality and safety, and minimize component
count and cost in smart battery circuits.
Fully Integrated High Accurate Clock
Flexible Configuration for 2 to 4 Series Li-Ion
The
Impedance
Track
technology
continuously
analyzes the battery impedance, resulting in superior
and Li-Polymer Cells
gas-gauging
accuracy.
This
enables
remaining
Integrated Field Programmable FLASH
capacity to be calculated with discharge rate,
Memory Eliminates the Need for External
temperature, and cell aging all accounted for during
Configuration Memory
each stage of every cycle.
Smart Battery Charger Control Feature
AVAILABLE OPTIONS
Two 16-Bit Delta-Sigma Converter
PACKAGE
Accurate Voltage and Temperature
T
A
Measurements
20-PIN TSSOP (PW)
20-PIN TSSOP (PW)
Tube
Tape & Reel
Integrating Coloumb Counter for Charge
40
C to
Flow
bq20z70PW
(1)
bq20z70PWR
(2)
85
C
Better Than 0.65 nVh of Resolution
Self-Calibrating
Supports SHA-1 Authentication
(1)
A single tube quantity is 50 units.
20-Pin TSSOP (PW)
(2)
A single reel quantity is 2000 units
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas
Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
IMPEDANCE TRACK is a trademark of Texas Instruments.
PRODUCTION DATA information is current as of publication date.
Copyright 20052006, Texas Instruments Incorporated
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
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SYSTEM PARTITIONING DIAGRAM
Charge Pumps
Overcurrent &
Short Circuit
Protection
C
e
l
l
S
e
l
e
c
t
i
o
n
M
u
l
t
i
p
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x
e
r
N-CH FET
Drive
Impedance
TrackTM Gas
Gauging
C
e
l
l
B
a
l
a
n
c
i
n
g
D
r
i
v
e
2
n
d
L
e
ve
l
V
o
l
t
a
g
e
P
r
o
t
e
c
t
i
o
n
Pack -
SMBus
Pack +
LDO
& Therm. Drive
& Reset
Therm
Fuse
Temperature
Measurement
& Protection
32kHz Clock
Generator
System
Interface
Voltage Level
Translator
Watchdog &
Protection
Timing
System
Interface
SHA-1
Authentication
Charging
Algorithm
SBS v1.1
Data
Cell & Pack
Voltage
Measurement
Overrcurrent
Protection
Overvoltage &
Undervoltage
Protection
Cell Balancing
Algorithm &
Control
Fail Safe
Protection
bq29330
Validation &
Control
bq20z70
bq29330
bq294xy
Supply Voltage
32KHz
I
2
C
Registers
Alert
RSNS
5m 20m
typ.
Reset
1
XALERT
2
TS2
3
TS1
4
CLKOUT
5
6
PFIN
7
SAFE
8
SMBD
9
NC
10
SMBC
VCELL -
20
VCELL +
19
VCC
18
VSS
17
MRST
16
SRN
15
SRP
14
VSS
13
SCLK
12
SDATA
11
PRES
bq20z70
SLUS686A NOVEMBER 2005 REVISED JUNE 2006
TSSOP (PW)
(TOP VIEW)
2
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ABSOLUTE MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICS
bq20z70
SLUS686A NOVEMBER 2005 REVISED JUNE 2006
TERMINAL FUNCTIONS
TERMINAL
I/O
(1)
DESCRIPTION
NO.
NAME
1
XALERT
I
Alert interrupt input from bq29330. Connect directly to bq29330 XALERT pin
2
TS2
I
2
nd
thermistor voltage input connection to monitor temperature
3
TS1
I
1
st
thermistor voltage input connection to monitor temperature
4
CLKOUT
O
32.768kHz output for bq29330 watchdog. Connect directly to bq29330 WDI pin
5
PRES
I
Active low input to sense system insertion
6
PFIN
I
Active low input to sense secondary protector output status
7
SAFE
O
Active high output to enforce additional level of safety, e.g. fuse blow
8
SMBD
I/OD
SMBus data open drain bidirectional pin used for communication with bq20z70
9
NC
Not used - leave floating
10
SMBC
I/OD
SMBus clock open drain bidirectional pin used for communication with bq20z70
11
SDATA
I/OD
Data transfer line from and to bq29330. Connect directly to SDATA pin of bq29330
12
SCLK
I/OD
Data clock line to bq29330. Connect directly to SCLK pin of bq29330
13
VSS
I/OD
VSS
14
SRP
IA
Connection for a small-value resistor to monitor the battery charge and discharge current flow
15
SRN
IA
Connection for a small-value resistor to monitor the battery charge and discharge current flow
Master reset input that forces the device into reset when held low. Connect directly to XRST pin of
16
MRST
I
bq29330
17
VSS
P
Negative supply. Both VSS needs to be connected together
18
VCC
P
Positive supply
19
VCELL+
I
Positive differential cell input. Connect directly to CELL+ pin of bq29330
20
VCELL-
I
Negative differential cell input. Connect directly to CELL- pin of bq29330
(1)
I = Input, IA = Analog input, I/O = Input/output, I/OD = Input/Open-drain output, O = Output, OA = Analog output, P = Power
over operating free-air temperature range (unless otherwise noted)
(1)
RANGE
V
CC
relative to V
SS
(2)
Supply voltage range on VCC pin
0.3 V to 2.75 V
V
(IOD)
relative to V
SS
(2)
XALERT, PFIN, SAFE, SMBD, SMBC, SDATA, SCLK,
0.3 V to 6.0 V
V
I
relative to V
SS
(2)
TS2, TS1, CLKOUT, PRES, SRP, SRN, MRST, VCELL+,VCELL-
0.3 V to V
CC
+ 0.3 V
T
A
Operating free-air temperature range
40
C to 85
C
T
stg
Storage temperature range
65
C to 150
C
(1)
Stresses beyond those listed under absolute maximum ratings may cause permanent damage to the device. These are stress ratings
only, and functional operation of the device at these or any other conditions beyond those indicated under recommended operating
conditions is not implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
(2)
V
SS
refers to Voltage at VSS pin.
V
CC
= 2.4 V to 2.6 V, T
A
= -40
C - 85
C (unless otherwise noted)
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
V
DD
Supply voltage
VDDA and VDDD
2.4
2.5
2.6
V
No flash programming
400
(1)
I
DD
Operating mode current
A
bq20z70 + bq29330
475
Sleep mode
8
(1)
I
(SLP)
Low-power storage mode current
A
bq20z70 + bq29330
48
(1)
This value does not include the bq29330
3
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bq20z70
SLUS686A NOVEMBER 2005 REVISED JUNE 2006
ELECTRICAL CHARACTERISTICS (continued)
V
CC
= 2.4 V to 2.6 V, T
A
= -40
C - 85
C (unless otherwise noted)
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
Shutdown Mode
0.1
(1)
I
(SLP)
Shutdown Current
A
bq20z70 + bq29330
0.2
Output voltage low CLKOUT, SAFE, SMBD, SMBC, SDATA,
I
OL
= 7 mA
0.4
V
OL
V
SCLK
V
OH
Output high voltage CLKOUT, SAFE, SMBD,SMBC, SDATA,
I
OH
= 0.5 mA
V
CC
0.5
V
SCLK
V
IL
Input voltage low PRES, PFIN, SMBD, SMBC, SDATA, MRST
0.8
V
V
IH
Input voltage high PRES, PFIN, SMBD, SMBC, SDATA, MRST
2.0
V
C
IN
Input capacitance
5
pF
V
(AI1)
Input voltage range TS1, TS2, VCELL+, VCELL-
0.2
0.8 x V
CC
V
V
(AI2)
Input voltage range SRP, SRN
0.2
0.2
Z
(AI1)
Input impedance TS1, TS2, VCELL+, VCELL -
0 V 1 V
8
M
Z
(AI2)
Input impedance SRP, SRN
0 V 1 V
2.5
M
4
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POWER-ON RESET
1.76
1.77
1.78
1.79
1.8
1.81
-40
-20
0
20
40
60
80
T - Free-Air Temperature - C
A
Power-OnResetNegative-GoingV
oltage-V
INTEGRATING ADC (Coulomb Counter) CHARACTERISTICS
OSCILLATOR
bq20z70
SLUS686A NOVEMBER 2005 REVISED JUNE 2006
V
CC
= 2.4 V to 2.6 V, T
A
= 40
C to 85
C (unless otherwise noted)
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
V
IT
Negative-going voltage input
1.7
1.8
1.9
V
V
HYS
Power-on reset hysteresis
50
125
200
mV
V
CC
= 2.4 V to 2.6 V, T
A
= 40
C to 85
C (unless otherwise noted)
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
V
(SR)
Input voltage range, V
(SRN)
and V
(SRP)
V
(SR)
= V(SRP) V(SRN)
0.20
0.20
V
V
(SROS)
Input offset
T
A
=25
C to 85
C
10
V
INL
Integral nonlinearity error
0.007
0.037
%
V
CC
= 2.4 V to 2.6 V, T
A
= 40
C to 85
C (unless otherwise noted)
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
HIGH FREQUENCY OSCILLATOR
f
(OSC)
Operating frequency
4.194
MHz
-3%
0.25%
3%
f
(EIO)
Frequency error
(1) (2)
T
A
= 20
C to 70
C
-2%
0.25%
2%
f
(sxo)
Start-up time
(3)
2.5
5
ms
LOW FREQUENCY OSCILLATOR
f
(LOSC)
Operating frequency
32.768
kHz
f
(LEIO)
-2.5%
0.25%
2.5%
Frequency error
(2) (4)
T
A
= 20
C to 70
C
-1.5%
0.25%
1.5%
f
(Lsxo)
Start-up time
(5)
500
s
(1)
The frequency error is measured from 4.194 MHz.
(2)
The frequency drift is included and measured f rom the trimmed frequency at V
CC
= 2.5 V, T
A
= 25
C.
(3)
The start-up time is defined as the time it takes for the oscillator output frequency to be within 1% of the specified frequency.
(4)
The frequency error is measured from 32.768 kHz.
(5)
The start-up time is defined as the time it takes for the oscillator output frequency to be
3%.
5
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