TI BQ2060A

bq2060A
SBS v1.1-Compliant Gas Gauge IC
Features
General Description
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The bq2060A SBS-Compliant Gas
Gauge IC for battery pack or
in-system installation maintains an
accurate record of available charge in
rechargeable batteries. The bq2060A
monitors capacity and other critical
battery parameters for NiCd, NiMH,
Li-Ion, and lead-acid chemistries.
The bq2060A uses a V-to-F converter
with automatic offset error correction
for charge and discharge counting.
For voltage, temperature, and current
reporting, the bq2060A uses an
A-to-D converter. The onboard ADC
also monitors individual cell voltages
in a Li-Ion battery pack and allows
the bq2060A to generate control signals that may be used in conjunction
with a pack supervisor to enhance
pack safety.
Provides accurate measurement
of available charge in NiCd,
NiMH, Li-Ion, and lead-acid
batteries
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Supports SBS Smart Battery
Data Specification v1.1
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Supports the 2-wire SMBus v1.1
interface with PEC or 1-wire
HDQ16
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Reports individual cell voltages
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Provides 15-bit resolution for
voltage, temperature, and current measurements
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Measures charge flow using a
V-to-F converter with offset of
less than 16µV after calibration
Monitors and provides control to
charge and discharge FETs in
Li-Ion protection circuit
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Consumes less than 0.5mW operating
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Drives a 4- or 5-segment LED
display for remaining capacity indication
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28-pin 150-mil SSOP
Pin Connections
HDQ16
ESCL
ESDA
RBI
REG
VOUT
VCC
VSS
DISP
LED1
LED2
LED3
LED4
LED5
1
2
3
4
5
6
7
8
9
10
11
12
13
14
28
27
26
25
24
23
22
21
20
19
18
17
16
15
The bq2060A supports the smart battery data (SBData) commands and
charge-control functions. It communicates data using the system management bus (SMBus) 2-wire protocol or
the Benchmarq 1-wire HDQ16 protocol. The data available include the
battery’s remaining capacity, temperature, voltage, current, and remaining run-time predictions. The
bq2060A provides LED drivers and a
push-button input to depict remaining
battery capacity from full to empty in
20% or 25% increments with a 4 or
5-segment display.
The bq2060A works with an external
EEPROM. The EEPROM stores the
configuration information for the
bq2060A, such as the battery’s chemistry, self-discharge rate, rate compensation factors, measurement calibration, and design voltage and capacity. The bq2060A uses the programmable self-discharge rate and
other compensation factors stored in
the EEPROM to accurately adjust remaining capacity for use and standby
conditions based on time, rate, and
temperature. The bq2060A also automatically calibrates or learns the true
battery capacity in the course of a discharge cycle from near-full to
near-empty levels.
The REG output regulates the operating voltage for the bq2060A from the
battery cell stack using an external
JFET.
Pin Names
SMBC
SMBD
VCELL4
VCELL3
VCELL2
VCELL1
SR1
SR2
SRC
TS
THON
CVON
CFC
DFC
28-Pin 150-mil SSOP
28PN2060.eps
HDQ16
Serial communication
input/output
ESCL
Serial memory clock
ESDA
Serial memory data and
address
RBI
Register backup input
REG
Regulator output
VOUT
EEPROM supply output
VCC
Supply voltage
VSS
Ground
DISP
Display control input
LED1–
LED5
LED display segment outputs
SLUS500A–OCTOBER 2001–REVISED MAY 2002
1
DFC
Discharge FET control
CFC
Charge FET control
VON
control
Cell voltage divider
THON
Thermistor bias control
TS
Thermistor voltage input
SRC
Current sense input
SR1–
SR2
Charge-flow sense resistor
inputs
VCELL1– Single-cell voltage inputs
VCELL4
SMBD
SMBus data
SMBC
SMBus clock
bq2060A
DFC
Pin Descriptions
HDQ16
Output to control the discharge FET in the
Li-Ion pack protection circuitry
Serial communication input/output
CFC
Open-drain bidirectional communications
port
ESCL
CVON
Serial memory data and address
THON
Thermistor bias control output
Output control for external FETs to connect
the thermistor bias resistor during a temperature measurement
Register backup input
TS
Input that provides backup potential to the
bq2060A registers during periods of low operating voltage. RBI accepts a storage capacitor or a battery input.
Thermistor voltage input
Input connection for a thermistor to monitor
temperature
SRC
REG
Cell voltage divider control output
Output control for external FETs to connect
the cells to the external voltage dividers
during cell voltage measurements
Bidirectional pin used to transfer address
and data to and from the bq2060A and the
external nonvolatile configuration memory
RBI
Charge FET control output
Output to control the charge FET in the
Li-Ion pack protection circuitry
Serial memory clock
Output to clock the data transfer between
the bq2060A and the external nonvolatile
configuration memory
ESDA
Discharge FET control output
Current sense voltage input
Regulator output
Input to monitor instantaneous current
Output to control an n-JFET for VCC regulation to the bq2060A from the battery potential
VOUT
SR1–
SR2
Input connections for a small value sense
resistor to monitor the battery charge and
discharge current flow
Supply output
Output that supplies power to the external
EEPROM configuration memory
VCC
Supply voltage input
VSS
Ground
DISP
Display control input
VCELL1–
VCELL4
Single-cell voltage inputs
Inputs that monitor the series element cell
voltages
SMBD
SMBus data
Open-drain bidirectional pin used to transfer address and data to and from the
bq2060A
Input that controls the LED drivers
LED1–LED5
LED1–
LED5
Sense resistor inputs
LED display segment outputs
SMBC
Outputs that each may drive an external
LED
SMBus clock
Open drain bidirectional pin used to clock
the data transfer to and from the bq2060A
2
bq2060A
The VFC measures bipolar signals up to 250mV. The
bq2060A detects charge activity when VSR = VSR2 –
VSR1 is positive and discharge activity when VSR = VSR2
– V S R 1 is negative. The bq2060A continuously
integrates the signal over time using an internal
counter. The fundamental rate of the counter is
6.25µVh.
Functional Description
General Operation
The bq2060A determines battery capacity by monitoring
the amount of charge input or removed from a rechargeable battery. In addition to measuring charge and discharge, the bq2060A measures battery voltage, temperature, and current, estimates battery self-discharge, and
monitors the battery for low-voltage thresholds. The
bq2060A measures charge and discharge activity by
monitoring the voltage across a small-value series sense
resistor between the battery’s negative terminal and the
negative terminal of the battery pack. The available
battery charge is determined by monitoring this voltage
and correcting the measurement for environmental and
operating conditions.
Offset Calibration
The bq2060A provides an auto-calibration feature to cancel the voltage offset error across SR1 and SR2 for maximum charge measurement accuracy. The calibration routine is initiated by issuing a command to
ManufacturerAccess(). The bq2060A is capable of automatic offset calibration down to 6.25µV. Offset cancellation
resolution is less than 1µV.
Digital Filter
Figure 1 shows a typical bq2060A-based battery-pack
application. The circuit consists of the LED display,
voltage and temperature measurement networks,
EEPROM connections, a serial port, and the sense resistor. The EEPROM stores basic battery-pack configuration information and measurement-calibration values.
The EEPROM must be programmed properly for
bq2060A operation. Table 9 shows the EEPROM memory map and outlines the programmable functions available in the bq2060A.
The bq2060A does not measure charge or discharge
counts below the digital filter threshold. The digital filter threshold is programmed in the EEPROM and
should be set sufficiently high to prevent false signal detection with no charge or discharge flowing through the
sense resistor.
Voltage
While monitoring SR1 and SR2 for charge and discharge
currents, the bq2060A monitors the battery-pack potential and the individual cell voltages through the
VCELL1–VCELL4 pins. The bq2060A measures the pack
voltage and reports the result in Voltage(). The bq2060A
can also measure the voltage of up to four series elements in a battery pack. The individual cell voltages
are stored in the optional Manufacturer Function area.
The bq2060A accepts an NTC thermistor (Semitec
103AT) for temperature measurement. The bq2060A
uses the thermistor temperature to monitor battery-pack temperature, detect a battery full-charge condition, and compensate for self-discharge and charge/discharge battery efficiencies.
Measurements
The VCELL1–VCELL4 inputs are divided down from the
cells using precision resistors, as shown in Figure 1. The
maximum input for VCELL1–VCELL4 is 1.25V with respect to VSS. The voltage dividers for the inputs must be
set so that the voltages at the inputs do not exceed the
1.25V limit under all operating conditions. Also, the divider ratios on VCELL1–VCELL2 must be half of that of
VCELL3–VCELL4. To reduce current consumption from
the battery, the CVON output may used to connect the
divider to the cells only during measurement period.
CVON is high impedance for 250ms (12.5% duty cycle)
when the cells are measured, and driven low otherwise.
(See Table 1.)
The bq2060A uses a fully differential, dynamically balanced voltage-to-frequency converter (VFC) for charge
measurement and a sigma delta analog-to-digital converter (ADC) for battery voltage, current, and temperature measurement.
Voltage, current, and temperature measurements are
made every 2–2.5 seconds, depending on the bq2060A
operating mode. Maximum times occur with compensated EDV, mWh mode, and maximum allowable discharge rate. Any AtRate computations requested or
scheduled (every 20 seconds) may add up to 0.5 seconds
to the time interval.
The SRC input of the bq2060A measures battery charge
and discharge current. The SRC ADC input converts
the current signal from the series sense resistor and
stores the result in Current(). The full-scale input range
to SBC is limited to ±250mV as shown in Table 2.
Charge and Discharge Counting
The VFC measures the charge and discharge flow of the
battery by monitoring a small-value sense resistor
between the SR1 and SR2 pins as shown in Figure 1.
3
bq2060A
Figure 1. Battery Pack Application Diagram–LED Display and Series Cell Monitoring
4
bq2060A
Table 1. Example VCELL1–VCELL4 Divider
and Input Range
Voltage Input
VCELL4
VCELL3
VCELL2
VCELL1
Voltage Division
Ratio
16
16
8
8
Current
The SRC input of the bq2060A measures battery charge
and discharge current. The SRC ADC input converts
the current signal from the series sense resistor and
stores the result in Current(). The full-scale input range
to SBC is limited to ±250mV, as shown in Table 2.
Full-Scale Input
(V)
20.0
20.0
10.0
10.0
Temperature
The TS input of the bq2060A in conjunction with an
NTC thermistor measures the battery temperature as
shown in Figure 1. The bq2060A reports temperature in
Temperature(). THON may be used to connect the bias
source to the thermistor when the bq2060A samples the
TS input. THON is high impedance for 60ms when the
temperature is measured, and driven low otherwise.
Table 2. SRC Input Range
Gas Gauge Operation
Sense Resistor (W)
Full-Scale Input
(A)
0.02
±12.5
0.03
±8.3
0.05
±5.0
0.10
±2.5
General
The operational overview in Figure 2 illustrates the gas
gauge operation of the bq2060A. Table 3 describes the
bq2060A registers.
The bq2060A accumulates a measure of charge and
discharge currents and estimates self-discharge of the
Figure 2. bq2060A Operational Overview
5
bq2060A
Table 3. bq2060A Register Functions
Function
Command Code
SMBus
HDQ16
SMBus
Access
Units
ManufacturerAccess
0x00
0x00
read/write
n/a
RemainingCapacityAlarm
0x01
0x01
read/write
mAh, 10mWh
RemainingTimeAlarm
0x02
0x02
read/write
minutes
BatteryMode
0x03
0x03
read/write
n/a
AtRate
0x04
0x04
read/write
mA, 10mW
AtRateTimeToFull
0x05
0x05
read
minutes
AtRateTimeToEmpty
0x06
0x06
read
minutes
AtRateOK
0x07
0x07
read
Boolean
Temperature
0x08
0x08
read
0.1°K
Voltage
0x09
0x09
read
mV
Current
0x0a
0x0a
read
mA
AverageCurrent
0x0b
0x0b
read
mA
MaxError
0x0c
0x0c
read
percent
percent
RelativeStateOfCharge
0x0d
0x0d
read
AbsoluteStateOfCharge
0x0e
0x0e
read
percent
RemainingCapacity
0x0f
0x0f
read
mAh, 10mWh
FullChargeCapacity
0x10
0x10
read
mAh, 10mWh
RunTimeToEmpty
0x11
0x11
read
minutes
AverageTimeToEmpty
0x12
0x12
read
minutes
AverageTimeToFull
0x13
0x13
read
minutes
ChargingCurrent
0x14
0x14
read
mA
ChargingVoltage
0x15
0x15
read
mV
Battery Status
0x16
0x16
read
n/a
CycleCount
0x17
0x17
read
cycles
DesignCapacity
0x18
0x18
read
mAh, 10mWh
DesignVoltage
0x19
0x19
read
mV
SpecificationInfo
0x1a
0x1a
read
n/a
ManufactureDate
0x1b
0x1b
read
n/a
SerialNumber
0x1c
0x1c
read
integer
Reserved
0x1d–0x1f
0x1d - 0x1f
-
-
ManufacturerName
0x20
0x20–0x25
read
string
string
DeviceName
0x21
0x28–0x2b
read
DeviceChemistry
0x22
0x30–0x32
read
string
ManufacturerData
0x23
0x38–0x3b
read
string
n/a
Pack Status
0x2f (LSB)
0x2f (LSB)
read/write
Pack Configuration
0x2f (MSB)
0x2f (MSB)
read/write
n/a
VCELL4
0x3c
0x3c
read/write
mV
VCELL3
0x3d
0x3d
read/write
mV
VCELL2
0x3e
0x3e
read/write
mV
VCELL1
0x3f
0x3f
read/write
mV
6
bq2060A
battery. The bq2060A compensates the charge current
measurement for temperature and state-of-charge of the
battery. It also adjusts the self-discharge estimation
based on temperature.
charge capacity of the battery. The last measured discharge of the battery is based on the value in the DCR
register after a qualified discharge occurs. Once updated, the bq2060A writes the new FCC value to
EEPROM in mAh to Last Measured Discharge. FCC
represents the full battery reference for the relative display mode and relative state of charge calculations.
The main counter RemainingCapacity() (RM) represents
the available capacity or energy in the battery at any
given time. The bq2060A adjusts RM for charge,
self-discharge, and leakage compensation factors. The
information in the RM register is accessible through the
communications ports and is also represented through
the LED display.
Discharge Count Register (DCR)
The DCR register counts up during discharge, independent of RM. DCR can continue to count even after RM has
counted down to 0. Prior to RM = 0, discharge activity,
light discharge estimation and self-discharge increment
DCR. After RM = 0, only discharge activity increments
DCR. The bq2060A initializes DCR to FCC – RM when
RM is within twice the programmed value in Near Full
EE 0x55. The DCR initial value of FCC – RM is reduced
by FCC/128 if SC = 0 (bit 2 in Control Mode) and is not
reduced if SC = 1. DCR stops counting when the battery
voltage reaches the EDV2 threshold on discharge.
The FullChargeCapacity() (FCC) register represents the
last measured full discharge of the battery. It is used as
the battery’s full-charge reference for relative capacity
indication. The bq2060A updates FCC when the battery
undergoes a qualified discharge from nearly full to a low
battery level. FCC is accessible through the serial communications ports.
The Discharge Count Register (DCR) is a non-accessible
register that only tracks discharge of the battery. The
bq2060A uses the DCR register to update the FCC register if the battery undergoes a qualified discharge from
nearly full to a low battery level. In this way, the
bq2060A learns the true discharge capacity of the battery under system use conditions.
Capacity Learning (FCC Update) and Qualified
Discharge
The bq2060A updates FCC with an amount based on the
value in DCR if a qualified discharge occurs. The new
value for FCC equals the DCR value plus the programmable nearly full and low battery levels, according to
the following equation:
Main Gas Gauge Registers
FCC(new) = DCR(final) =
(1)
DCR(initial) + measured discharge to EDV2
+(FCC´ Battery Low% )
RemainingCapacity() (RM)
RM represents the remaining capacity in the battery.
The bq2060A computes RM in either mAh or 10mWh depending on the selected mode.
where
Battery Low % = (value stored in EE 0x54) ¸ 2.56
A qualified discharge occurs if the battery discharges
from RM ≥ FCC - Near Full * 2 to the EDV2 voltage
threshold with the following conditions:
On initialization, the bq2060A sets RM to 0. RM counts
up during charge to a maximum value of FCC and down
during discharge and self-discharge to 0. In addition to
charge and self-discharge compensation, the bq2060A
calibrates RM at three low-battery-voltage thresholds,
EDV2, EDV1, and EDV0 and three programmable
midrange thresholds VOC25, VOC50, and VOC75. This
provides a voltage-based calibration to the RM counter.
n
n
DesignCapacity() (DC)
The DC is the user-specified battery full capacity. It is
calculated from Pack Capacity EE 0x3a–0x3b and is represented in mAh or 10mWh. It also represents the
full-battery reference for the absolute display mode.
n
n
FullChargeCapacity() (FCC)
FCC is the last measured discharge capacity of the battery. It is represented in either mAh or 10mWh depending on the selected mode. On initialization, the bq2060A
sets FCC to the value stored in Last Measured Discharge EE 0x38–0x39. During subsequent discharges,
the bq2060A updates FCC with the last measured dis-
n
n
7
No valid charge activity occurs during the discharge
period. A valid charge is defined as an input of
10mAh into the battery.
No more than 256mAh of self-discharge and/or light
discharge estimation occurs during the discharge
period.
The temperature does not drop below 5°C during the
discharge period.
The battery voltage reaches the EDV2 threshold
during the discharge period and the voltage was less
than the EDV2 threshold minus 256mV when the
bq2060A detected EDV2.
No midrange voltage correction occurs during the
discharge period.
There is no overload condition when voltage ≤ EDV2
threshold
bq2060A
FCC cannot be reduced by more than 256mAh or increased by more than 512mAh during any single update
cycle. The bq2060A saves the new FCC value to the
EEPROM within 4s of being updated.
rate. This method maintains a constant granularity of
0.39% for each self-discharge adjustment, which may be
performed multiple times per day, instead of once per
day with a potentially large reduction.
End-of-Discharge Thresholds and Capacity Correction
The self-discharge estimation rate for 25°C is doubled
for each 10 degrees above 25°C or halved for each 10 degrees below 25°C. The following table shows the relation
of the self-discharge estimation at a given temperature
to the rate programmed for 25°C (Y% per day):
The bq2060A monitors the battery for three low-voltage
thresholds, EDV0, EDV1, and EDV2. The EDV thresholds are programmed in EDVF/EDV0 EE 0x72–0x73,
EMF/EDV1 EE 0x74–0x75, and EDV C1/C0 Factor/EDV2 EE 0x78–0x79. If the CEDV bit in Pack Configuration is set, automatic EDV compensation is enabled and the bq2060A computes the EDV0, EDV1, and
EDV2 thresholds based on the values in EE 0x72–0x7d,
0x06, and the battery’s current discharge rate, temperature, capacity, and cycle count. The bq2060A disables
EDV detection if Current() exceeds the Overload Current
threshold programmed in EE 0x46 - EE 0x47. The
bq2060A resumes EDV threshold detection after Current() drops below the overload current threshold. Any
EDV threshold detected will be reset after 10mAh of
charge are applied.
Temp < 10
1
Y%
4
1
Y%
2
10 ≤ Temp <20
20 ≤ Temp <30
The bq2060A uses the thresholds to apply voltage-based
corrections to the RM register according to Table 4.
per day
per day
Y% per day
30 ≤ Temp <40
2Y% per day
40 ≤ Temp <50
4Y% per day
50 ≤ Temp <60
8Y% per day
60 ≤ Temp <70
16Y% per day
70 ≤ Temp
32Y% per day
The interval at which RM is reduced is given by the following equation, where n is the appropriate factor of 2
(n = 14 , 12 , 1, 2, . . . ):
Table 4. State of Charge Based
on Low Battery Voltage
Threshold
EDV0
EDV1
EDV2
Self-Discharge Rate
Temperature ( C)
(2)
Self - Discharge Update Time =
State of Charge in RM
0%
3%
Battery Low %
640·13500
256· n · (Y % per day)
seconds
The timer that keeps track of the self-discharge update
time is halted whenever charge activity is detected. The
timer is reset to zero if the bq2060A reaches the
RemainingCapacity()=FullChargeCapacity() condition
while charging.
The bq2060A adjusts RM as it detects each threshold. If
the voltage threshold is reached before the corresponding capacity on discharge, the bq2060A reduces RM to
the appropriate amount as shown in Table 4. If RM
reaches the capacity level before the voltage threshold is
reached on discharge, the bq2060A prevents RM from
decreasing until the battery voltage reaches the corresponding threshold, but only on a full learning-cycle discharge (VDQ = 1). The EDV1 threshold is ignored if Miscellaneous Options bit 7 = 1.
Example: If T = 35°C (n = 2) and programmed
self-discharge rate Y is 2.5 (2.5% per day at 25°C), the
bq2060A reduces RM by RM/256 (0.39%) every
(3)
640·13500
256· n· (Y % per day)
= 6750 seconds
This means that a 0.39% reduction of RM will be made
12.8 times per day to achieve the desired 5% per day reduction at 35°C.
Self-Discharge
The bq2060A estimates the self-discharge of the battery
to maintain an accurate measure of the battery capacity
during periods of inactivity. The algorithm for
self-discharge estimation takes a programmed estimate
for the expected self-discharge rate at 25°C stored in
EEPROM and makes a fixed reduction to RM of an
amount equal to RemainingCapacity()/256. The bq2060A
makes the fixed reduction at a varying time interval
that is adjusted to achieve the desired self-discharge
Figure 3 illustrates how the self-discharge estimate algorithm adjusts RemainingCapacity() vs. temperature.
Light Discharge or Suspend Current
Compensation
The bq2060A can be configured in two ways to compensate for small discharge currents that produce a signal
8
bq2060A
Threshold
Associated State of Charge
VOC25
25%
VOC50
50%
VOC75
75%
For the midrange corrections to occur, the temperature
must be in the range of 19°C to 31°C inclusive and the
Current() and AverageCurrent() must both be between
–64mA and 0. For a correction to occur, the bq2060A
must also detect the need for correction during two adjacent measurements separated by 20s. The second measurement is not required if the first measurement is immediately after a device reset. The bq2060A makes
midrange corrections as shown in Table 5.
Figure 3. Self-Discharge at 2.5%/Day @25C
Charge Control
below the digital filter. First, the bq2060A can decrement
RM and DCR at a rate determined by the value stored in
Light Discharge Current EE 0x2b when it detects no discharge activity and the SMBC and SMBD lines are high.
Light Discharge Current has a range of 44µA to 11.2mA.
Charging Voltage and Current Broadcasts
The bq2060A supports SBS charge control by broadcasting
the ChargingCurrent() and ChargingVoltage() to the
Smart Charger address. The bq2060A broadcasts the requests every 10s. The bq2060A updates the values used
in the charging current and voltage broadcasts based on
the battery’s state of charge, voltage, and temperature.
The fast-charge rate is programmed in Fast-Charging
Current EE 0x1a - 0x1b while the charge voltage is programmed in Charging Voltage EE 0x0a-0x0b.
Alternatively, the bq2060A can be configured to disable
the digital filter for discharge when the SMBC and
SMBD lines are high. In this way, the digital filter will
not mask the leakage current signal. The bq2060A is
configured in this mode by setting the NDF bit in Control Mode.
The bq2060A internal charge control is compatible with
popular rechargeable chemistries. The primary
charge-termination techniques include a change in temperature over a change in time (∆T/∆t) and current
taper, for nickel-based and Li-Ion chemistries, respectively. The bq2060A also provides pre-charge qualification and a number of safety charge suspensions based
on current, voltage, temperature, and state of charge.
Midrange Capacity Corrections
The bq2060A applies midrange capacity corrections
when the VCOR bit is set in Pack Configuration. The
bq2060A adjusts RM to the associated percentage at
three different voltage levels VOC25, VOC50, and
VOC75. The VOC values represent the open circuit battery voltage at which RM corresponds to the associated
state of charge for each threshold.
Table 5. Midrange Corrections
Condition
Voltage()
Result
≥ VOC75 and RelativeStateOfCharge() ≤ 63%
RelativeStateOfCharge()→75%
< VOC75 and RelativeStateOfCharge() ≥ 87%
RelativeStateOfCharge()→75%
≥VOC50 and RelativeStateOfCharge() ≤ 38%
RelativeStateOfCharge()→50%
<VOC50 and RelativeStateOfCharge() ≥ 62%
RelativeStateOfCharge()→50%
≥ VOC25 and RelativeStateOfCharge() ≤ 13%
RelativeStateOfCharge()→25%
< VOC25 and RelativeStateOfCharge() ≥ 37%
RelativeStateOfCharge()→25%
9
bq2060A
is no longer being charged (DISCHARGING bit set in
BatteryStatus()). The bq2060A continues to broadcast
zero charging current until the overvoltage condition is
cleared. The overvoltage condition is cleared when the
measured
battery
voltage
drops
below
the
ChargingVoltage() plus the Overvoltage Margin or when
the CVOV bit is reset.
Alarm Broadcasts to Smart Charger and Host
If any of the bits 8–15 in BatteryStatus() is set, the
bq2060A broadcasts an AlarmWarning() message to the
Host address. If any of the bits 12–15 in BatteryStatus() is
set, the bq2060A also sends an AlarmWarning() message
to the Smart Charger address. The bq2060A repeats the
AlarmWarning() message every 10s until the bits are
cleared.
n
Pre-Charge Qualification
The bq2060A sets ChargingCurrent() to the pre-charge
rate as programmed in Pre-Charge Current EE
0x1e-0x1f under the following conditions:
n
n
Voltage:
The bq2060A requests the pre-charge
charge rate when Voltage() drops below the EDV0
threshold (compensated or fixed EDVs). Once
requested, a pre-charge rate remains until Voltage()
increases above the EDVF threshold. The bq2060A
also broadcasts the pre-charge value immediately
after a device reset until Voltage() is above the EDVF
threshold. This threshold is programmed in
EDVF/EDV0 EE 0x72-0x73.
n
Temperature:
The bq2060A requests the
pre-charge rate when Temperature() is between 0°C
and 5°C. Temperature() must rise above 5°C before
the bq2060A requests the fast-charge rate.
Charge Suspension
The bq2060A may temporarily suspend charge if it detects a charging fault. A charging fault includes the following conditions.
n
n
Overcurrent: An overcurrent condition exists when
the bq2060A measures the charge current to be more
than
the
Overcurrent
Margin
above
the
ChargingCurrent(). Overcurrent Margin is programmed
in EE 0x49. On detecting an overcurrent condition, the
bq2060A sets the ChargingCurrent() to zero and sets the
TERMINATE_CHARGE_ALARM bit in Battery
Status(). The overcurrent condition and TERMINATE_
CHARGE_ALARM are cleared when the measured
current drops below the ChargingCurrent plus the
Overcurrent Margin.
n
Over-Temperature: An over-temperature condition
exists when Temperature() is greater than or equal to
the Max T value programmed in EE 0x45 (most
significant nibble). On detecting an over-temperature
condition, the bq2060A sets the ChargingCurrent() to
zero and sets the OVER_TEMP_ALARM and
TERMINATE_CHARGE_
ALARM
bit
in
BatteryStatus() and the CVOV bit in Pack Status.
The over-temperature condition is cleared when
Temperature() is equal to or below (Max T – 5°C).
The temperature set by MaxT is increased by 16°C if
bit 5 in Miscellaneous Options is set.
Overcharge: An overcharge condition exists if the
battery is charged more than the Maxmum
Overcharge value after RM = FCC. Maximum
Overcharge is programmed in EE 0x2e–0x2f. On
detecting an overcharge condition, the bq2060A sets
the ChargingCurrent() to zero and sets the
OVER_CHARGED_ALARM, TERMINATE_CHARGE_
ALARM,
and
FULLY_CHARGED
bits
in
BatteryStatus(). The bq2060A clears the OVER_
CHARGED_ALARM and TERMINATE_CHARGE_
ALARM when it detects that the battery is no longer
being charged. The FULLY_CHARGED bit remains set
and the bq2060A continues to broadcast zero charging
current until RelativeStateOfCharge() is less than
Fully Charged Clear% programmed in EE 0x4c.The
counter used to track overcharge capacity is reset
with 2mAh of discharge.
Under-Temperature:
An
under-temperature
condition exists if Temperature() < 0°C. On detecting
an under temperature condition, the bq2060A sets
ChargingCurrent() to zero. The bq2060A sets
ChargingCurrent() to the appropriate pre-charge rate
or fast-charge rate when Temperature() ≥ 0°C.
Primary Charge Termination
The bq2060A terminates charge if it detects a
charge-termination condition. A charge-termination
condition includes the following.
Overvoltage: An overvoltage condition exists when the
bq2060A measures the battery voltage to be more than
the Overvoltage Margin above the ChargingVoltage() or
a Li-Ion cell voltage has exceeded the overvoltage limit
programmed in Cell Under-/Overoltage. Overvoltage
Margin is programmed in EE 0x48 and Cell Under/Over
Voltage in EE 0x4a (least significant nibble). On
detecting an overvoltage condition, the bq2060A sets the
ChargingCurrent()
to
zero
and
sets
the
TERMINATE_CHARGE_ALARM bit in BatteryStatus().
The
bq2060A
clears
the
TERMINATE_
CHARGE_ALARM bit when it detects that the battery
n
10
∆T/∆t: For ∆T/∆t, the bq2060A detects a change in
temperature over many seconds. The ∆T/∆t setting
is programmable in both the temperature step,
DeltaT (1.6°C - 4.6°C), and the time step, DeltaT
Time (20s-320s). Typical settings for 1°C/minute
include 2°C/120s and 3°C/180s. Longer times are
required for increased slope resolution. The DeltaT
value is programmed in EE 0x45 (least significant
nibble) and the Delta T Time in EE 0x4e.
bq2060A
In addition to the ∆T/∆t timer, a hold-off timer starts
when the battery is being charged at more than
255mA and the temperature is above 25°C. Until this
timer expires, ∆T/∆t detection is suspended. If
Current() drops below 256mA or Temperature() below
25°C, the hold-off timer resets and restarts only when
the current and temperature conditions are met again.
The hold-off timer is programmable (20s – 320s) with
Holdoff Time value in EE 0x4f.
n
LED bit in Control Mode programs the 4 or 5 LED option. A 5th LED can be used with the 4 LED display option to show when the battery capacity is ≥ to 100%.
Activation
The display may be activated at any time by a
high-to-low transition on the DISP input. This is usually
accomplished with a pullup resistor and a pushbutton
switch. Detection of the transition activates the display and starts a four-second display timer. The timer
expires and turns off the display whether DISP was
brought low momentarily or held low indefinitely. Reactivation of the display requires that the DISP input return to a logic-high state and then transition low again.
The second high-to-low transition must occur after the
display timer expires. The bq2060A requires the DISP
input to remain stable for a minimum of 250ms to detect
the logic state.
Current Taper: For current taper, ChargingVoltage()
must be set to the pack voltage desired during the
constant-voltage phase of charging. The bq2060A detects
a current taper termination when the pack voltage is
greater than the voltage determined by Current Taper
Qual Voltage in EE 0x4f and the charging current is
below a threshold determined by Current Taper
Threshold in EE 0x4e, for at least 80s. The bq2060A uses
the VFC to measure current for current taper
termination. The current must also remain above
0.5625/RS mA to qualify the termination condition.
If the EDV0 bit is set, the bq2060A disables the LED
display. The display is also disabled during a VFC calibration and should be turned off before entering
low-power storage mode.
Once the bq2060A detects a primary charge termination,
it sets the TERMINATE_CHARGE_ALARM and
FULLY_CHARGED bits in BatteryStatus(), and sets
the ChargingCurrent() to the maintenance charge rate
as programmed in Maintenance Charging Current EE
0x1c–0x1d. On termination, the bq2060A also sets RM
to a programmed percentage of FCC, provided that
RelativeStateOfCharge() is below the desired
percentage of FCC and the CSYNC bit in Pack Configuration EE 0x3f is set. If the CSYNC bit is not set and
RelativeStateOfCharge() is less than the programmed
percentage of FCC, the bq2060A clears the
FULLY_CHARGED bit in BatteryStatus(). The programmed percentage of FCC, Fast Charge Termination
%, is set in EE 0x4b. The bq2060A clears the
FULLY_CHARGED bit when RelativeStateOfCharge()
is less than the programmed Fully Charged Clear %.
The bq2060A broadcasts the fast-charge rate when the
FULLY_CHARGED bit is cleared and voltage and temperature permit. The bq2060A clears the TERMINATE_CHARGE_ALARM when it no longer detects
that the battery is being charged or it no longer detects
the termination condition. See Table 6 for a summary
of BatteryStatus() alarm and status bit operation.
Display Modes
In relative mode, each LED output represents 20% or
25% of the RelativeStateOfCharge() value. In absolute
mode, each LED output represents 20% or 25% of the
AbsoluteStateOfCharge() value. Tables 7A and 7B show
the display operation.
In either mode, the bq2060A blinks the LED display if
R em a in in g C a p a c it y ( ) is les s t h a n R em a in in g
CapacityAlarm(). The display is disabled if EDV0 = 1.
Secondary Protection for Li-Ion
The bq2060A has two pins, CFC and DFC, that can be
used for secondary override control of a Li-Ion protector
or for blowing a fuse to disable the battery pack. The
CFC pin is the Charge FET Control pin for secondary
protector control or for blowing a fuse. The DFC pin is
the Discharge FET Control pin for secondary protector
control. Discharge current can cause an override of the
CFC control, and charge current can cause an override
of the DFC control. Pack Status can read the CVOV
and CVUV status flags and can also read the true logic
state of the CFC and DFC pins.
Display Port
General
The display port drives a 4 or 5 LED bar-graph display.
The display is activated by a logic signal on the DISP input. The bq2060A can display RM in either a relative or
absolute mode with each LED representing a percentage
of the full-battery reference. In relative mode, the
bq2060A uses FCC as the full-battery reference; in absolute mode, it uses DC.
The CVOV status flag is set if Voltage() ≥ Charging
Voltage() + Overvoltage Margin, any VCELL voltage ≥
Cell Overvoltage threshold, or if Temperature() ≥ MaxT.
When CVOV=1 and Miscellaneous Options bit 6 = 0, the
CFC pin is pulled low unless DISCHARGING bit in
BatteryStatus() is set or Temperature() > Safety
Overtemperature threshold. If Miscellaneous Options bit
6 = 1, the CPC pin is pulled low only if Temperature()
>Safety Overtemperature threshold.
The DMODE bit in Pack Configuration programs the
bq2060A for the absolute or relative display mode. The
11
bq2060A
Table 6. Alarm and Status Bit Summary
Battery State
Conditions
Overcurrent
C() ≥ CC() + Overcurrent
Margin
Overvoltage
V() ≥ CV() + Overvoltage
Margin
VCELL1, 2, 3, or 4 > Cell
Over Voltage
CC() State and
BatteryStatus Bits Set
CC() = Fast or Pre-charge Current
and/or Bits Cleared
CC() = 0, TCA = 1
C() < CC() + Overcurrent Margin
TCA = 1
DISCHARGING = 1
CC() = 0, CVOV = 1
V() < CV() + Overvoltage Margin
Li-Ion cell voltage ≤ Cell Over Voltage
Overtemperature
T() ≥ Max T
CC() = 0, OTA = 1,
TCA = 1, CVOV = 1
T() ≤ Max T - 5°C or T() ≤ 43°C
Capacity added after
RM() = FCC() ≥
Maximum Overcharge
CC() = 0, FC = 1
RSOC() < Fully Charged Cleared %
Overcharge
OCA = 1, TCA = 1
DISCHARGING = 1
T() < 0°C
CC() = 0
0°C ≤ Τ() < 5°C, CC() = Pre-Charge
Current
T() ≥ 5°C, CC() = Fast-Charging Current
CC() = Maintenance
Charging Current,
FC = 1
RSOC() < Fully Charged Cleared %
TCA = 1
DISCHARGING = 1 or termination
condition is no longer valid.
V() ≤ EDV2
or
RM() < FCC() * Battery
Low%
FD = 1
RSOC() > 20%
V() ≤ EDV0
TDA = 1
V() > EDV0
VCELL1, 2, 3 or 4 < Cell
Under Voltage
TDA = 1, CVUV = 1
VCELL1, 2, 3, or 4 ≥ Cell Under Voltage
RM() = 0
TDA = 1
RM() > 0
Low capacity
RM() < RCA()
RCA = 1
RM() ≥ RCA()
Low run-time
ATTE() < RTA()
RTA = 1
ATTE() ≥ RTA()
Undertemperature
Fast charge
termination
Fully discharged
Overdischarged
Note:
∆T/∆t or Current Taper
C() = Current(), CV() = ChargingVoltage(), CC() = ChargingCurrent(), V() = Voltage(), T() = Temperature(), TCA = TERMINATE_CHARGE_ALARM, OTA = OVER_TEMPERATURE_ALARM,
OCA = OVER_CHARGED_ALARM, TDA = TERMINATE_DISCHARGE_ALARM, FC =
FULLY_CHARGED,
FD = FULLY_DISCHARGED, RSOC() = RelativeStateOfCharge(). RM() = RemainingCapacity(),
RCA = REMAINING_CAPACITY_ALARM, RTA = REMAINING_TIME_ALARM,
ATTE() = AverageTimeToEmpty(), RTA() = RemainingTimeAlarm(), RCA() = RemainingCapacityAlarm(),
FCC() = FullChargeCapacity.
12
bq2060A
Table 7A. Display Mode
Condition
Relative or
Absolute
StateOfCharge()
Table 7B. Display Mode
5 LED Display Option
Condition
Relative or
Absolute
StateOfCharge()
4 LED Display Option
LED1
LED2 LED3 LED4 LED5
LED1
LED2
LED3
LED4
EDV0 = 1
OFF
OFF
OFF
OFF
OFF
EDV0 = 1
OFF
OFF
OFF
OFF
<20%
ON
OFF
OFF
OFF
OFF
<25%
ON
OFF
OFF
OFF
≥20%, <40%
ON
ON
OFF
OFF
OFF
≥25%, <50%
ON
ON
OFF
OFF
≥40%, <60%
ON
ON
ON
OFF
OFF
≥50%, <75%
ON
ON
ON
OFF
≥60%, <80%
ON
ON
ON
ON
OFF
≥75%
ON
ON
ON
ON
≥80%
ON
ON
ON
ON
ON
The CVUV status flag is set if any VCELL voltage < Cell
Undervoltage threshold. When CVUV = 1, the DVC pin
i s pu l l e d l o w unl e s s D I S C H A R G I NG b it in
BatteryStatus() is set or Temperature() is not set.
partial reset leaves MaxError, RELEARN_FLAG, and
RM unchanged. The bq2060A delays reading the
EEPROM for 700ms after all resets to allow settling
time for VCC.
Cell Undervoltage and Cell Overvoltage limits may be
programmed in the upper and lower nibbles of EE 0x4a.
Safety Overtemperature threshold may be programmed
in EE 0x09, and Miscellaneous Options is programmed
in EE 0x08.
Communication
The bq2060A includes two types of communication
ports: SMBus and HDQ16. The SMBus interface is a
2-wire bidirectional protocol using the SMBC (clock) and
SMBD (data) pins. The HDQ16 interface is a 1-wire
bidirectional protocol using the HDQ16 pin. All three
communication lines are isolated from VCC and may be
pulled-up higher than VCC. Also, the bq2060A will not
pull these lines low if VCC to the part is zero . HDQ16
should be pulled down with a 100KΩ resistor if not
used.
Low-Power Storage Mode
The bq2060A enters low-power mode 5– 8s after receiving the Enable Low-Power command. In this mode the
bq2060A consumes less than 10µA. A rising edge on
SMBC, SMBD, or HDQ16 restores the bq2060A to the
full operating mode. The bq2060A does not perform any
gas gauge functions during low-power storage mode.
The communication ports allow a host controller, an
SMBus compatible device, or other processor to access
the memory registers of the bq2060A. In this way a system can efficiently monitor and manage the battery.
Device Reset
The bq2060A can be reset when power is applied or by
commands over the HDQ16 or SMBus. Upon reset, the
bq2060A initializes its internal registers with the information contained in the configuration EEPROM. The
following command sequence initiates a full bq2060A reset:
SMBus
The SMBus interface is a command-based protocol. A
processor acting as the bus master initiates communication to the bq2060A by generating a START condition. A
START condition consists of a high-to-low transition of
the SMBD line while the SMBC is high. The processor
then sends the bq2060A device address of 0001011 (bits
7–1) plus a R/W bit (bit 0) followed by an SMBus command code. The R/W bit and the command code instruct
the bq2060A to either store the forthcoming data to a
register specified by the SMBus command code or output the data from the specified register. The processor
completes the access with a STOP condition. A STOP
condition consists of a low-to-high transition of the
SMBD line while the SMBC is high. With SMBus, the
most significant bit of a data byte is transmitted first.
Write 0xff5a to address 0x4f
Write 0x0000 to address 0x7d
Write 0x0080 to address 0x7d
A partial reset of the bq2060A occurs if step 1 is omitted
and all check-byte values previously loaded into RAM
are still correct. All initial RAM values are read from
EEPROM for both full and partial resets. A full reset
initializes MaxError = 100%, sets RELEARN_FLAG (bit
7) = 1 in Battery Mode, and initializes RM from EE
0x2c–2d (should be zero for rechargeable batteries). A
13
bq2060A
In some instances, the bq2060A acts as the bus master.
This occurs when the bq2060A broadcasts charging requirements and alarm conditions to device addresses
0x12 (SBS Smart Charger) and 0x10 (SBS Host Controller.)
= X8 + X2 + X1 + 1. The PEC calculation includes all
bytes in the transmission, including address, command,
and data. The PEC calculation does not include ACKNOWLEDGE, NOT ACKNOWLEDGE, START, STOP,
and Repeated START bits.
SMBus Protocol
n
Read Word
For example, the host requests RemainingCapacity()
from the bq2060A. This includes the host following the
Read Word protocol. The bq2060A calculates the PEC
based on the following 5 bytes of data, assuming the remaining capacity of the battery is 1001mAh.
n
Write Word
n
Battery Address with R/W = 0: 0x16
n
Read Block
n
Command Code for RemainingCapacity(): 0x0f
n
Battery Address with R/W = 1: 0x17
n
RemainingCapacity(): 0x03e9
The bq2060A supports the following SMBus protocols:
A processor acting as the bus master uses the three protocols to communicate with the bq2060A. The bq2060A
acting as the bus master uses the Write Word protocol.
For 0x160f17e903, the bq2060A transmits a PEC of 0xe8
to the host.
The SMBD and SMBC pins are open drain and require
external pullup resistors.
PEC Enable in Master Mode
SMBus Packet Error Checking
PEC for master mode broadcasts to the charger, host, or
both can be enabled/disabled with the combination of
the bits HPE and CPE in Control Mode.
The bq2060A supports Packet Error Checking as a mechanism to confirm proper communication between it and
another SMBus device. Packet Error Checking requires
that both the transmitter and receiver calculate a Packet
Error Code (PEC) for each communication message. The
device that supplies the last byte in the communication
message appends the PEC to the message. The receiver
compares the transmitted PEC to its PEC result to determine if there is a communication error.
SMBus On and Off State
The bq2060A detects whether the SMBus enters the Off
State” by monitoring the SMBC and SMBD lines. When
both signals are continually low for at least 2.5s, the
bq2060A detects the Off State. When the SMBC and
SMBD lines go high, the bq2060A detects the On State
and can begin communication within 1ms. One-MΩ
pulldown resistors on SMBC and SMBD are recommended for reliable Off State detection.
PEC Protocol
The bq2060A can receive or transmit data with or without PEC. Figure 4 shows the communication protocol
for the Read Word, Write Word, and Read Block messages without PEC. Figure 5 includes PEC.
HDQ16
The HDQ16 interface is a command-based protocol. (See
Figure 6.) A processor sends the command code to the
bq2060A. The 8-bit command code consists of two fields,
the 7-bit HDQ16 command code (bits 0–6) and the 1-bit
R/W field. The R/W field directs the bq2060A either to
In the Write Word protocol, the bq2060A receives the
PEC after the last byte of data from the host. If the host
does not support PEC, the last byte of data is followed
by a STOP condition. After receipt of the PEC, the
bq2060A compares the value to its calculation. If the
PEC is correct, the bq2060A responds with an ACKNOWLEDGE. If it is not correct, the bq2060A responds with a NOT ACKNOWLEDGE and sets an error
code.
n
Store the next 16 bits of data to a specified register or
n
Output 16 bits of data from the specified register
With HDQ16, the least significant bit of a data byte
(command) or word (data) is transmitted first.
In the Read Word and Block Read, the host generates an
ACKNOWLEDGE after the last byte of data sent by the
bq2060A. The bq2060A then sends the PEC and the
host acting as a master-receiver generates a NOT ACKNOWLEDGE and a STOP condition.
A bit transmission consists of three distinct sections. The
first section starts the transmission by either the host or
the bq2060A taking the HDQ16 pin to a logic-low state
for a period tSTRH;B . The next section is the actual
data-transmission, where the data bit is valid by the
time, tDSU;B after the negative edge used to start communication. The data bit is held for a period tDH;DV to allow
the host processor or bq2060A to sample the data bit.
PEC Calculation
The basis of the PEC calculation is an 8-bit Cyclic Redundancy Check (CRC-8) based on the polynomial C(X)
14
bq2060A
Figure 4. SMBus Communication Protocol without PEC
Figure 5. SMBus Communication Protocol with PEC
15
bq2060A
The final section is used to stop the transmission by returning the HDQ16 pin to a logic-high state by at least
the time tSSU;B after the negative edge used to start
communication. The final logic-high state should be until a period tCYCH;B to allow time to ensure that the bit
transmission was stopped properly.
LEDs must be off before entering the low-power storage
mode as the display state remains unchanged.
The bq2060A clears the ManufacturerAccess() command
within 900ms of acknowledging the Enable Low-Power
Storage command. The VFC Calibration command may
be sent 900–5000ms after SMBus acknowledgment of
the Enable Low-Power Storage command. In this case,
the bq2060A delays entering storage mode until the calibration process completes and the bq2060A stores the
new calibration values in EEPROM.
If a communication error occurs (e.g., tCYCB > 250µs), the
host sends the bq2060A a BREAK to reinitiate the serial
interface. The bq2060A detects a BREAK when the
HDQ16 pin is in a logic-low state for a time t B or
greater. The HDQ16 pin is then returned to its normal
ready-high logic state for a time tBR. The bq2060A is
then ready to receive a command from the host processor.
0x062b SEAL: Instructs the bq2060A to restrict access
to those functions listed in Table 3. The bq2060A completes the seal function and clears ManufacturerAccess()
within 900ms of acknowledging the command.
The HDQ16 pin is open drain and requires an external
pullup resistor.
0x064d Charge Synchronization: Instructs the
bq2060A to update RM to a percentage of FCC as
defined in Fast Charge Termination %. The bq2060A
updates RM and clears ManufacturerAccess() within
900ms of acknowledging the command.
Command Codes
The SMBus Command Codes are in ( ), the HDQ16 in [ ].
Temperature(), Voltage(), Current(), and AverageCurrent(),
performance specifications are at regulated VCC (VRO)
and a temperature of 0–70°C.
0x0653 Enable VFC Calibration: Instructs the unsealed bq2060A to begin VFC calibration. With this
command the bq2060A deselects the SR1 and SR2 inputs
and calibrates for IC offset only. It is best to avoid
charge or discharge currents through the sense resistor
during this calibration process.
ManufacturerAccess() (0x00); [0x00–0x01]
Description:
This function provides writable command codes to control the bq2060A during normal operation and pack
manufacture. These commands can be ignored if sent
within one second after a device reset. The following list
of commands are available.
0x067e Alternate VFC Calibration: Instructs the
unsealed bq2060A to begin VFC calibration. With this
command, the bq2060A does not deselect the SR1 and
SR2 inputs and does calibrate for IC and PCB offset.
During this procedure no charge or discharge currents
0x0618 Enable Low-Power Storage Mode: Activates
the low-power storage mode. The bq2060A enters the
storage mode after a 5–8s delay. The bq2060A accepts
other commands to ManufacturerAccess() during the
delay before entering low-power storage mode. The
During VFC calibration, the bq2060A disables the LED
display and accepts only the Stop VFC Calibration and
Figure 6. HDQ16 Communication Example
16
bq2060A
bration command. This delays the low-power
storage mode until after VFC calibration completion.
the SEAL commands to ManufacturerAccess(). The
bq2060A disregards all other commands. SMBus
communication should be kept to a minimum during
VFC calibration to reduce the noise level and allow a
more accurate calibration.
5.
Once started, the VFC calibration procedure completes
automatically. When complete, the bq2060A saves the
calibration values in EEPROM. The calibration normally takes about 8 to 10 minutes. The calibration time
is inversely proportional to the bq2060A VFC (and PCB)
offset error. The bq2060A caps the calibration time at
one hour in the event of calibrating zero offset error. The
VFC calibration can be done as the last step in a battery
pack test procedure since the calibration can complete
automatically after removal from a test setup.
After VFC calibration completes automatically, the
bq2060A saves the VFC offset cancellation values in
EEPROM and enters the low-power storage mode in
about 20s. In addition, the bq2060A is sealed, allowing
access as defined in Table 3 only.
Purpose:
The ManufacturerAccess() function provides the system
host access to bq2060A functions that are not defined by
the SBD.
The bq2060A clears ManufacturerAccess() within 900ms
and starts calibration within 3.2s of acknowledging the
command.
0x0660 Stop VFC Calibration: Instructs the bq2060A
to abort a VFC calibration procedure. If aborted, the
bq2060A disables offset correction. The bq2060A stops
calibration within 20ms of acknowledging the command.
SMBus Protocol: Read or Write Word
Input/Output: Word
RemainingCapacityAlarm() (0x01); [0x01]
0x0606 Program EEPROM: Instructs the unsealed
bq2060A to connect the SMBus to the EEPROM I2C bus.
The bq2060A applies power to the EEPROM within
900ms of acknowledging the command. After issuing the
program EEPROM command, the bq2060A monitoring
functions are disabled until the I2C bus is disconnected.
The bq2060A disconnects the I2C bus when it detects that
the Battery Address 0x16 is sent over the SMBus. The
Battery Address 0x16 to disconnect the I2C bus should
not be sent until 10ms after the last write to the
EEPROM.
Description:
Sets or gets the low-capacity threshold value. Whenever
the RemainingCapacity() falls below the low capacity
value, the bq2060A sends AlarmWarning() messages to
the SMBus Host with the REMAINING_CAPACITY_ALARM bit set. A low-capacity value of 0 disables
this alarm. The bq2060A initially sets the low-capacity
value to Remaining Capacity Alarm value programmed
in EE 0x04 - 0x05. The low-capacity value remains unc h a n g ed u n t il a lt er ed b y t h e R em a in in g CapacityAlarm() function. The low-capacity value may
be expressed in either current (mA) or power (10mWh)
depending on the setting of the BatteryMode()’s CAPACITY_MODE bit.
Example: The following sequence of actions is an example of how to use the ManufacturerAccess() commands
in an efficient manner to take a battery pack that has
completed all testing and calibration except for VFC calibration and to make it ready for shipment in the
SEALED state and in low-power storage mode:
1. Complete testing and calibration with desired final
values stored in EEPROM. This process includes
setting the SEAL bit in Pack Configuration.
Sending a reset command to the bq2060A during
test ensures that RAM values correspond to the final EEPROM values
2.
Purpose:
The RemainingCapacityAlarm() function can be used by
systems that know how much power they require to
save their operating state. It enables those systems to
more finely control the point at which they transition
into suspend or hibernate state. The low-capacity value
can be read to verify the value in use by the bq2060’s
low capacity alarm.
SMBus Protocol: Read or Write Word
If the initial value of RemainingCapacity() must be
non-zero, the desired value may be written to Command 0x26 with the pack unsealed. A reset sent after this step resets RM to zero.
3.
Issue the Enable Low-Power Storage Mode command.
4.
Within 900–1600ms after sending the Enable
Low-Power command, issue the Enable VFC Cali-
Issue the SEAL Command subsequent to the VFC
Calibration command. The bq2060A must receive
the SEAL Command before VFC calibration completes. The bq2060A resets the OCE bit in Pack
Status when calibration begins and sets the bit
when calibration successfully completes.
Input/Output: Unsigned integer—value below which
Low Capacity messages are sent.
17
bq2060A
Battery Modes
CAPACITY_MODE CAPACITY_MODE
bit = 0
bit = 1
Units
mAh @ C/5
10mWh @ P/5
Range
0–65,535mAh
0–65,535 10mWh
Granularity
Not applicable
Accuracy
See RemainingCapacity()
n
The defined request condition is the battery requesting
a conditioning cycle (RELEARN_FLAG).
Purpose:
The CAPACITY_MODE bit allows power management
systems to best match their electrical characteristics
with those reported by the battery. For example, a
switching power supply represents a constant power
load, whereas a linear supply is better represented by a
constant current model. The CHARGER_MODE bit allows a SMBus Host or Smart Battery Charger to override the Smart Battery’s desired charging parameters by
d is a b lin g t h e b q 2 0 6 0 ’s b r oa d c a s t s . T h e RELEARN_FLAG bit allows the bq2060A to request a conditioning cycle.
RemainingTimeAlarm() (0x02); [0x02]
Description:
Sets or gets the remaining time alarm value. Whenever the
AverageTimeToEmpty() falls below the remaining time
value, the bq2060A sends AlarmWarning() messages to the
SMBus Host with the REMAINING_TIME_ALARM bit set.
A remaining time value of 0 effectively disables this alarm.
The bq2060A initially sets the remaining time value to the
Remaining Time Alarm value programmed in EE 0x02 0x03. The remaining time value remains unchanged until
altered by the RemainingTimeAlarm() function.
SMBus Protocol: Read or Write Word
Input/Output:
Unsigned integer —bit mapped— see below.
Units: not applicable
Purpose:
The RemainingTimeAlarm() function can be used by systems that want to adjust when the remaining time
alarm warning is sent. The remaining time value can be
read to verify the value in use by the bq2060’s
RemainingTimeAlarm().
Range: 0–1
Granularity: not applicable
Accuracy: not applicable
The BatteryMode() word is divided into two halves, the
most significant bit (bits 8–15), which is read/write and
the least significant bit (bits 0–7), which is read only.
The bq2060A forces bits 0–6 to zero and prohibits writes
to bit 7.
SMBus Protocol: Read or Write Word
Input/Output:
Unsigned integer—the point below which remaining time messages are sent.
Table 8 summarizes the meanings of the individual bits
in the BatteryMode() word and specifies the default values, where applicable, are noted.
Units: minutes
Range: 0 to 65,535 minutes
INTERNAL_CHARGE_CONTROLLER bit is not
used by the bq2060A.
Granularity: Not applicable
Accuracy: see AverageTimeToEmpty()
PRIMARY_BATTERY_SUPPORT bit is not used by
the bq2060A.
BatteryMode() (0x03); [0x03]
Description:
This function selects the various battery operational
modes and reports the battery’s mode and requests.
RELEARN_FLAG bit set indicates that the bq2060A is
requesting a capacity relearn cycle for the battery. The
bq2060A sets the RELEARN_FLAG under any of three
conditions: full reset, detection of 20 cycle counts without an FCC update, or a midrange voltage correction.
The bq2060A clears this flag after a learning cycle has
been completed.
Defined modes include
n
n
Whether all broadcasts to the Smart Battery Charger
and Host are disabled
Whether the battery’s capacity information is
specified in mAh or 10mWh (CAPACITY_MODE bit)
CHARGE_CONTROLLER_ENABLED bit is not used
by the bq2060A. The bq2060A forces this bit to zero.
Whether the ChargingCurrent() and ChargingVoltage()
values are broadcast to the Smart Battery Charger
when the bq2060A detects the battery requires charging
(CHARGER_MODE bit)
PRIMARY_BATTERY bit is not used by the bq2060A.
The bq2060A forces this bit to zero.
18
bq2060A
Table 8. Battery Mode Bits and Values
Battery Mode() Bits
INTERNAL_CHARGE_CONTROLLER
PRIMARY_BATTERY_SUPPORT
Reserved
Bits Used
0
1
2–6
Format
Read only bit flag
Read only bit flag
RELEARN_FLAG
7
Read only bit flag
CHARGE_CONTROLLER_ENABLED
PRIMARY_BATTERY
Reserved
8
9
10–12
R/W bit flag
R/W bit flag
ALARM_MODE
13
R/W bit flag
CHARGER_MODE
14
R/W bit flag
CAPACITY_MODE
15
R/W bit flag
n
n
0—Battery OK
1—Relearn cycle requested
0—Enable alarm broadcast (default)
1—Disable alarm broadcast
0—Enable charging broadcast
(default)
1—Disable charging broadcast
0—Report in mA or mAh (default)
1—Report in 10mW or 10mWh
Charger. When set, the bq2060A does NOT transmit
ChargingCurrent() and ChargingVoltage() values to the
Smart Battery Charger. When cleared, the bq2060A
transmits the ChargingCurrent() and ChargingVoltage()
v a lu es t o t h e S m a r t B a t t er y C h a r g er . T h e
CHARGER_MODE bit defaults to a cleared state within
130ms after the bq2060A detects the SMBus Off-State.
ALARM_MODE bit is set to disable the bq2060’s ability
to master the SMBus and send AlarmWarning() messages
to the SMBus Host and the Smart Battery Charger. When
set, the bq2060A does NOT master the SMBus, and
AlarmWarning() messages are NOT sent to the SMBus
Host and the Smart Battery Charger for a period of no
more than 65s and no less than 45s. When cleared
(default), the Smart Battery sends the AlarmWarning()
messages to the SMBus Host and the Smart Battery
Charger any time an alarm condition is detected.
n
Allowable Values
CAPACITY_MODE bit indicates if capacity information is reported in mA/mAh or 10mW/10mWh. When
set, the bq2060A reports capacity information in
10mW/10mWh as appropriate. When cleared, the
bq2060A reports capacity information in mA/mAh as appropriate. The CAPACITY_MODE bit defaults to a
cleared state within 130ms after the bq2060A detects
the SMBus Off-State.
The bq2060A polls the ALARM_MODE bit at least
every 150ms. Whenever the ALARM_MODE bit is set,
the bq2060A resets the bit and starts or restarts a 55s
(nominal) timer. After the timer expires, the bq2060A
automatically enables alarm broadcasts to ensure that
the accidental deactivation of broadcasts does not
persist. To prevent the bq2060A from becoming a
master on the SMBus, an SMBus host must therefore
continually set this bit at least once per 50s to keep
the bq2060A from broadcasting alarms.
Note 1: The following functions are changed to accept or
return values in mA/mAh or 10mW/10mWh depending
on the CAPACITY_MODE bit:
The ALARM_MODE bit defaults to a cleared state
within 130ms after the bq2060A detects the SMBus
Off-State.
The condition of the ALARM-MODE bit does NOT
affect the operation or state of the CHARGER_MODE
bit which is used to prevent broadcasts of
ChargingCurrent() and ChargingVoltage() to the
Smart Battery Charger.
n
RemainingCapacityAlarm()
n
AtRate()
n
RemainingCapacity()
n
FullChargeCapacity()
n
DesignCapacity()
Note 2: The following functions are calculated on the
basis of capacity and may be calculated differently depending on the CAPACITY_MODE bit:
CHARGER_MODE bit enables or disables the bq2060’s
t ra n smi s s i o n
of
C har g i ng C ur r e n t ( )
and
ChargingVoltage() messages to the Smart Battery
19
bq2060A
n
AtRateOK()
SMBus Protocol: Read or Write Word
n
AtRateTimeToEmpty()
n
AtRateTimeToFull()
Input/Output: Signed integer—charge or discharge;
the AtRate() value is positive for charge, negative for
discharge, and zero for neither (default).
n
RunTimeToEmpty()
n
AverageTimeToEmpty()
n
AverageTimeToFull()
n
Remaining Time Alarm()
n
BatteryStatus()
Units
Charge
Range
Discharge
Range
Granularity
Accuracy
The bq2060A updates the non-AtRate related register
values within 3s of changing the state of the CAPACITY_MODE bit. The AtRate() values will be updated after the next AtRate value is written to the bq2060A (or
after the next 20s scheduled refresh calculation).
AtRate() (0x04); [0x04]
n
1–32,768 10mW
-1– -32,768mA
-1– -32,768 10mW
1 Unit
NA
Description:
Returns the predicted remaining time to fully charge
the battery at the AtRate( ) value (mA).
Purpose:
T h e A t R a t eTim eToF u ll( ) f u n c t ion is p a r t of a
two-function call-set used to determine the predicted
remaining charge time at the AtRate value in mA. The
bq2060A updates AtRateTimeToFull() within 1.3s after
the SMBus Host sets the AtRate value. If read before
this delay, the command is No Acknowledged and the error code in BatteryStatus is set to not ready. The
bq2060A automatically updates AtRateTimeToFull()
based on the AtRate() value every 20s.
Purpose:
Since the AtRate() function is the first half of a
two-function call-set, it is followed by the second function of the call-set that calculates and returns a value
based on the AtRate value and the battery’s present
state. A delay of up to 1.3s is required after writing
AtRate() before the bq2060A can acknowledge the requested AtRate function.
n
1–32,767mA
AtRateTimeToFull() (0x05);[0x05]
Description:
The AtRate() function is the first half of a two-function
call-set used to set the AtRate value used in calculations
made by the AtRateTimeToFull(), AtRateTimeToEmpty(), and AtRateOK() functions. The AtRate
value may be expressed in either current (mA) or power
(10mW) depending on the setting of the BatteryMode()’s
CAPACITY_MODE bit.
n
Battery Mode
CAPACITY_MODE CAPACITY_MODE
bit = 0
bit = 1
mA
10mW
SMBus Protocol: Read Word
When the AtRate() value is positive, the AtRateTimeToFull() function returns the predicted time to
full-charge at the AtRate value of charge.
Output:
Unsigned integer—predicted time in minutes to
fully charge the battery.
When the AtRate() value is negative, the
AtRateTimeToEmpty() function returns the predicted
operating time at the AtRate value of discharge.
Units: minutes
When the AtRate() value is negative, the AtRateOK()
function returns a Boolean value that predicts the
battery’s ability to supply the AtRate value of
additional discharge energy (current or power) for 10
seconds.
Range: 0 to 65,534 min
Granularity: 2 min or better
Accuracy: ±MaxError() *
FullChargeCapacity()/|AtRate()|
The default value for AtRate() is zero. Writing
AtRate() values over the HDQ16 serial port does NOT
trigger a re-calculation of AtRateTimeToFull(),
AtRateTimeToEmpty(), and AtRateOK() functions.
Invalid Data Indication: 65,535 indicates the battery is not being charged.
It is recommended that AtRate() requests should be limited to one request every 4s.
20
bq2060A
AtRateTimeToEmpty() (0x06); [0x06]
Range: TRUE, FALSE
Description:
Returns the predicted remaining operating time if the
battery is discharged at the AtRate() value.
Granularity: not applicable
Purpose:
The AtRateTimeToEmpty() function is part of a
two-function call-set used to determine the remaining
operating time at the AtRate()value. The bq2060A updates AtRateTimeToEmpty() within 1.3s after the
SMBus Host sets the AtRate() value. If read before this
delay, the command is No Acknowledged, and the error
code in BatteryStatus is set to not ready. The bq2060A
automatically updates AtRateTimeToEmpty() based on
the AtRate() value every 20s.
Temperature() (0x08); [0x08]
Accuracy: not applicable
Description:
Returns the temperature (K) measured by the bq2060A.
SMBus Protocol: Read Word
Purpose:
The Temperature() function provides accurate cell temperatures for use by battery chargers and thermal management systems. A battery charger can use the temperature as a safety check. Thermal management systems may use the temperature because the battery is
one of the largest thermal sources in a system.
Output:
SMBus Protocol: Read Word
Output:
Unsigned integer — estimated operating time left.
U n s ig n ed in t eg er — c ell t em p er a t u r e
tenth-degree Kelvin increments.
Units: minutes
Range: 0 to 65,534 min
in
Units: 0.1°K
Granularity: 2 min or better
Range: 0 to +6553.5°K {real range}
Accuracy: -0, +MaxError() *
FullChargeCapacity/|AtRate()|
Granularity: 0.1°K
Accuracy: ±1.5°K (from ideal 103AT thermistor
performance, after calibration)
Invalid Data Indication: 65,535 indicates the battery is not being discharged.
Voltage() (0x09); [0x09]
AtRateOK() (0x07); [0x07]
Description:
Returns the cell-pack voltage (mV).
Description:
Returns a Boolean value that indicates whether or not
the battery can deliver the AtRate( )value of additional
energy for 10 seconds (Boolean). If the AtRate value is
zero or positive, the AtRateOK() function ALWAYS return-true.
Purpose:
The Voltage() function provides power management systems with an accurate battery terminal voltage. Power
management systems can use this voltage, along with
battery current information, to characterize devices they
control. This ability helps enable intelligent, adaptive
power-management systems.
Purpose:
The AtRateOK() function is part of a two-function
call-set used by power management systems to determine if the battery can safely supply enough energy for
an additional load. The bq2060A updates AtRateOK()
within 1.3s after the SMBus Host sets the AtRate( )
value. If read before this delay, the command is No Acknowledged, and the error code in BatteryStatus is set
to not ready. The bq2060A automatically updates
AtRateOK() based on the At Rate() value every 20s.
SMBus Protocol: Read Word
Output:
Unsigned integer—battery terminal
voltage in mV.
Units: mV
SMBus Protocol: Read Word
Range: 0 to 20,000 mV
Output:
Granularity: 1mV
Boolean—indicates if the battery can
supply the additional energy requested.
Accuracy: ±0.65% (after calibration)
Units: Boolean
21
bq2060A
Current() (0x0a); [0x0a]
the Relative StateOfCharge() is more likely between 50
and 60%. The bq2060A sets MaxError() to 100% on a
full reset. The bq2060A sets MaxError() to 2% on completion of a learning cycle, unless the bq2060A limits
the learning cycle to the +512/-256mAh maximum adjustment values. If the learning cycle is limited, the
bq2060A sets MaxError() to 8% unless MaxError() was
already below 8%. In this case MaxError() does not
change. The bq2060A increments MaxError() by 1% after four increments of CycleCount() without a learning
cycle.
Description:
Returns the current being supplied (or accepted)
through the battery’s terminals (mA).
Purpose:
The Current() function provides a snapshot for the
power management system of the current flowing into or
out of the battery. This information is of particular use
in power-management systems because they can characterize individual devices and tune their operation to actual system power behavior.
If voltage-based corrections are applied to the coulomb
counter, MaxError() is set to 25%.
SMBus Protocol: Read Word
Output:
Purpose:
The MaxError() function has real value in two ways:
first, to give the user a confidence level about the state
of charge and second, to give the power management
system information about how aggressive it should be,
particularly as the battery nears the end of its life.
Signed integer—charge/discharge rate in mA increments—positive for charge, negative for discharge.
Units: mA
Range: (± 250mV/RS) mA
SMBus Protocol: Read Word
Granularity: 0.038mV/RS (integer value)
Output:
Accuracy: ±1mV/RS (after calibration)
Unsigned integer—percent uncertainty for selected
information.
AverageCurrent() (0x0b); [0x0b]
Description:
Returns a value that approximates a one-minute rolling
average of the current being supplied (or accepted)
t h ro u g h the b a tte r y ’s te r m i nal s ( m A ) .
The
AverageCurrent() function will return meaningful values during the battery’s first minute of operation.
Units: %
Range: 2 to 100%
Granularity: 1%
Accuracy: not applicable
Purpose:
The AverageCurrent() function provides the average current flowing into or out of the battery for the power
management system.
RelativeStateOfCharge() (0x0d); [0x0d]
Description:
Returns the predicted remaining battery capacity expressed as a percentage of FullChargeCapacity() (%).
SMBus Protocol: Read Word
Signed integer—charge/discharge rate in mA increments—positive for charge, negative for discharge.
Purpose:
The RelativeStateOfCharge() function is used to estimate the amount of charge remaining in the battery relative to the last learned capacity.
Units: mA
SMBus Protocol: Read Word
Range: (± 250mV/RS) mA
Output:
Output:
Granularity: 0.038mV/RS (integer value)
Unsigned integer—percent of remaining capacity.
Accuracy: ±1mV/RS (after calibration)
Units: %
MaxError() (0x0c); [0x0c]
Range: 0 to 100%
Description:
Returns the expected margin of error (%) in the state of
charge calculation. For example, when MaxError() returns 10% and RelativeStateOfCharge() returns 50%,
Granularity: 1%
Accuracy: -0, +MaxError()
22
bq2060A
AbsoluteStateOfCharge()(0x0e); [0x0e]
FullChargeCapacity() (0x10); [0x10]
Description:
Returns the predicted remaining battery capacity expressed as a percentage of DesignCapacity() (%). Note
that AbsoluteStateOfCharge() can return values greater
than 100%.
Description:
Returns the predicted pack capacity when it is fully
charged. The FullChargeCapacity() value is expressed
in either current (mAh at a C/5 discharge rate) or power
(10mWh at a P/5 discharge rate) depending on the setting of the BatteryMode()’s CAPACITY_MODE bit.
Purpose:
The AbsoluteStateOfCharge() function is used to estimate the amount of charge remaining in the battery relative to the nominal or DesignCapacity().
Purpose:
The FullChargeCapacity() function provides the user
with a means of understanding the tank size of their
battery. This information, along with information about
the original capacity of the battery, can be presented to
the user as an indication of battery wear.
SMBus Protocol: Read Word
Output:
SMBus Protocol: Read Word
Unsigned integer—percent of remaining capacity.
Output:
Units: %
Unsigned integer—estimated full-charge capacity
in mAh or 10mWh.
Range: 0 to 100+%
Granularity: 1%
Battery Mode
CAPACITY_MODE CAPACITY_MODE
bit = 0
bit = 1
Units
mAh
10mWh
Range
0–65,535mAh
0–65,535 10mWh
Granularity
mAh
10mWh
Accuracy
-0, +MaxError() ∗ FullChargeCapacity()
Accuracy: -0, +MaxError()
RemainingCapacity() (0x0f); [0x0f]
Description:
Returns the predicted charge or energy remaining in the
battery. The RemainingCapacity() value is expressed in
either charge (mAh at a C/5 discharge rate) or energy
(10mWh at a P/5 discharge rate) depending on the setting of the BatteryMode()’s CAPACITY_MODE bit.
RunTimeToEmpty() (0x11); [0x11]
Purpose:
The RemainingCapacity() function returns the battery’s
remaining capacity. This information is a numeric indication of remaining charge or energy given by the Absolute
or Relative StateOfCharge() functions and may be in a
better form for use by power management systems.
Description:
Returns the predicted remaining battery life at the presen t r a t e of d is c h a r g e ( m in u t es ) .
The
RunTimeToEmpty() value is calculated based on either
current or power depending on the setting of the
BatteryMode()’s CAPACITY_MODE bit.
SMBus Protocol: Read Word
Purpose:
The RunTimeToEmpty() provides the power management
system with information about the relative gain or loss in
remaining battery life in response to a change in power
policy. This information is NOT the same as the
AverageTimeToEmpty(), which is not suitable to determine the effects that result from a change in power policy.
Output:
Unsigned integer—remaining charge in mAh or
10mWh.
Battery Mode
CAPACITY_MODE CAPACITY_MODE
bit = 0
bit = 1
Units
mAh
10mWh
Range
0–65,535mAh
0–65,535 10mWh
Granularity
mAh
10mWh
Accuracy
-0, +MaxError() ∗ FullChargeCapacity()
SMBus Protocol: Read Word
Output:
Unsigned integer—minutes of operation left.
Units: minutes
Range: 0 to 65,534 min
Granularity: 2 min or better
23
bq2060A
Accuracy: -0, +MaxError() ∗ FullChargeCapacity()
/ Current()
ChargingCurrent() (0x14); [0x14]
Description: Returns the desired charging rate in mA.
Invalid Data Indication: 65,535 indicates battery is
not being discharged.
Purpose: The ChargingCurrent() function sets the
m a x im u m c h a r g e c u r r en t of t h e b a t t er y. T h e
ChargingCurrent() value should be used in combination
with the ChargingVoltage() value to set the charger’s operating point. Together, these functions permit the
bq2060A to dynamically control the charging profile
(current/voltage) of the battery. The bq2060A can effectively turn off a charger by returning a value of 0 for
this function. The charger may be operated as a constant-voltage source above its maximum regulated current range by returning a ChargingCurrent() value of
65,535.
AverageTimeToEmpty() (0x12); [0x12]
Description: Returns a one-minute rolling average of
the predicted remaining battery life (minutes). The
AverageTimeToEmpty() value is calculated based on either current or power depending on the setting of the
BatteryMode()’s CAPACITY_MODE bit.
Purpose:
The AverageTimeToEmpty() displays state-of-charge information in a more useful way. It averages the instantaneous estimations so the remaining time does not appear to jump around.
SMBus Protocol: Read Word
Output:
SMBus Protocol: Read Word
Unsigned integer—maximum charger output current in mA.
Output:
Unsigned integer — minutes of operation left.
Units: mA
Units: minutes
Range: 0 to 65,535mA
Range: 0 to 65,534 min
Granularity: 1mA
Granularity: 2 min or better
Accuracy: not applicable
Accuracy: -0, +MaxError() ∗ FullChargeCapacity()
/ AverageCurrent()
Invalid Data Indication: 65,535 indicates that a
charger should operate as a voltage source outside
its maximum regulated current range.
Invalid Data Indication: 65,535 indicates battery is
not being discharged.
ChargingVoltage() (0x15); [0x15]
AverageTimeToFull() (0x13); [0x13]
Description: Returns the desired charging voltage in
mV.
Description: Returns a one-minute rolling average of
the predicted remaining time until the battery reaches
full charge (minutes).
Unsigned integer —remaining time in minutes.
Purpose: The ChargingVoltage() function sets the maxim u m c h a r g e v olt a g e of t h e b a t t er y. T h e
ChargingVoltage() value should be used in combination
with the ChargingCurrent() value to set the charger’s
operating point. Together, these functions permit the
bq2060A to dynamically control the charging profile
(current/voltage) of the battery. The charger may be operated as a constant-current source above its maximum
r eg u la t ed v olt a g e r a n g e b y r et u r n in g a
ChargingVoltage() value of 65,535.
Units: minutes
SMBus Protocol: Write Word
Range: 0 to 65,534 minutes
Output:
Purpose: The AverageTimeToFull() function can be
used by the SMBus Host’s power management system to
aid in its policy. It may also be used to find out how long
the system must be left on to achieve full charge.
SMBus Protocol: Read Word
Output:
Granularity: 2 minutes or better
Unsigned integer—charger output voltage in mV.
Accuracy: MaxError() ∗ FullChargeCapacity() /
AverageCurrent()
Units: mV
Range: 0 to 65,535mV
Invalid Data Indication: 65,535 indicates the battery is not being charged.
Granularity: 1mV
24
bq2060A
Accuracy: not applicable
Alarm Bits
Invalid Data Indication: 65,535 indicates that the
charger should operate as a current source outside
its maximum regulated voltage range.
OVER_CHARGED_ALARM bit is set whenever the
bq2060A detects that the battery is being charged beyond the Maximum Overcharge limit. This bit is cleared
when the bq2060A detects that the battery is no longer
being charged (i.e., the bq2060A detects discharge activity or no activity for the digital filter timeout periods.
The digital filter timeout period (seconds) equates to 10
time the value shared in Digital Filter EE0x52.)
BatteryStatus()(0x16); [0x16]
Description: Returns the bq2060’s status word (flags).
Some of the BatteryStatus() flags (REMAINING_CAPACITY_ALARM and REMAINING_TIME_ALARM)
are calculated based on either current or power depending on the setting of the BatteryMode()’s CAPACITY_MODE bit. This is important because use of the
wrong calculation mode may result in an inaccurate
alarm.
TERMINATE_CHARGE_ALARM bit is set when the
bq2060A detects that one or more of the battery’s charging parameters are out of range (e.g., its voltage, current, or temperature is too high) or when the bq2060A
detects a primary charge termination. This bit is
cleared when the parameter falls back into the allowable range, the termination condition ceases, or when
the bq2060A detects that the battery is no longer being
charged.
Purpose: The BatteryStatus() function is used by the
power-management system to get alarm and status bits,
as well as error codes from the bq2060A. This is basically the same information broadcast to both the SMBus
H o st a n d t he S m ar t B at te r y C har ger b y t h e
A l a rmWar ni ng ( ) f unc ti o n e x c e p t t h a t t h e
AlarmWarning() function sets the Error Code bits all
high before sending the data.
OVER_TEMP_ALARM bit is set when the bq2060A detects that the internal battery temperature is greater
than or equal to the MaxT limit. This bit is cleared
when the internal temperature falls back into the acceptable range.
TERMINATE_DISCHARGE_ALARM bit is set when
the bq2060A detects Voltage() ≤ EDV0, the CVUV bit in
Pack Status is set (Li-Ion cell voltage has dropped below
the limit programmed in Cell Under / Over Voltage), or
RemainingCapacity() = 0. The bit is cleared when Volta g e( ) > E D V 0 or C V U V b it is c lea r ed , a n d
RemainingCapacity() > 0.
SMBus Protocol: Read Word
Output:
Unsigned integer—Status Register with alarm conditions bit mapped as follows:
0x8000
0x4000
0x2000
0x1000
0x0800
0x0400
0x0200
0x0100
0x0080
0x0040
0x0020
0x0010
0x0007
0x0006
0x0005
0x0004
0x0003
0x0002
0x0001
0x0000
REMAINING_CAPACITY_ALARM bit is set when the
bq2060A detects that RemainingCapacity() is less than
that set by the RemainingCapacityAlarm() function.
This bit is cleared when either the value set by the
RemainingCapacityAlarm() function is lower than
RemainingCapacity() or when the RemainingCapacity()
is increased by charging.
Alarm Bits
OVER_CHARGED_ALARM
TERMINATE_CHARGE_ALARM
reserved
OVER_TEMP_ALARM
TERMINATE_DISCHARGE_ALARM
reserved
REMAINING_CAPACITY_ALARM
REMAINING_TIME_ALARM
Status Bits
INITIALIZED
DISCHARGING
FULLY_CHARGED
FULLY_DISCHARGED
Error Codes
Unknown Error
BadSize
Overflow/Underflow
AccessDenied
UnsupportedCommand
ReservedCommand
Busy
OK
REMAINING_TIME_ALARM bit is set when the
bq2060A detects that the estimated remaining time at
the present discharge rate is less than that set by the
RemainingTimeAlarm() function. This bit is cleared when
either the value set by the RemainingTimeAlarm() function is lower than the AverageTimeToEmpty() or when the
AverageTimeToEmpty() is increased by charging.
Status Bits
INITIALIZED bit is set when the bq2060A is has detected a valid load of EEPROM. It is cleared when the
bq2060A detects an improper EEPROM load.
DISCHARGING bit is set when the bq2060A determines that the battery is not being charged. This bit is
cleared when the bq2060A detects that the battery is being charged.
25
bq2060A
Granularity: 1 cycle
FULLY_CHARGED bit is set when the bq2060A detects a primary charge termination or an overcharged
condition. It is cleared when RelativeStateOfCharge() ≤
the programmed Fully Charged Clear % in EE 0x4c.
Accuracy: absolute count
DesignCapacity() (0x18); [0x18]
FULLY_DISCHARGED bit is set when Voltage() ≤
EDV2 threshold, or RemainingCapacity() < Full Charge
Capacity * BatteryLow%. This bit is cleared when the
Relative StateOfCharge() is ≥ 20%.
Description: Returns the theoretical or nominal capacity of a new pack. The DesignCapacity() value is expressed in either current (mAh at a C/5 discharge rate)
or power, (10mWh at a P/5 discharge rate) depending on
the setting of the BatteryMode()’s CAPACITY_MODE
bit.
Error Codes
Description
The bq2060A processed the function
OK
code without detecting any errors.
The bq2060A is unable to process the
Busy
function code at this time.
The bq2060A detected an attempt to
read or write to a function code
reserved by this version of the
Reserved
specification. The 2060 detected an
attempt to access an unsupported
optional manufacturer function code.
The bq2060A does not support this
Unsupported
function code which is defined in this
version of the specification.
The bq2060A detected an attempt to
AccessDenied
write to a read-only function code.
The bq2060A detected a data overflow
Over/Underflow
or underflow.
The bq2060A detected an attempt to
BadSize
write to a function code with an
incorrect data block.
The bq2060A detected an
UnknownError
unidentifiable error.
Purpose: The DesignCapacity() function is used by the
SMBus Host’s power management in conjunction with
FullChargeCapacity() to determine battery wear. The
power management system may present this information to the user and also adjust its power policy as a result.
SMBus Protocol: Read Word
Output:
Unsigned integer—battery capacity in mAh or
10mWh.
Battery Mode
CAPACITY_MODE CAPACITY_MODE
bit = 0
bit = 1
Units
mAh
10mWh
Range
0–65,535mAh
0–65,535 10mWh
Granularity
Not applicable
Accuracy
Not applicable
DesignVoltage() (0x19); [0x19]
CycleCount()(0x17); [0x17]
Description: Returns the theoretical voltage of a new
pack (mV). The bq2060A sets DesignVoltage() to the
value programmed in Design Voltage EE0x12–0x13.
Description: Returns the number of cycles the battery
has experienced. The mAh value of each count is determined by programming the Cycle Count Threshold value
in EE 0x3c–0x3d. The bq2060A saves the cycle count
value to Cycle Count EE 0x0e–0x0f after an update to
CycleCount().
Purpose: The DesignVoltage() function can be used to
give additional information about a particular Smart
Battery’s expected terminal voltage.
SMBus Protocol: Read Word
Purpose: The CycleCount() function provides a means
to determine the battery’s wear. It may be used to give
advanced warning that the battery is nearing its end of
life.
Output:
SMBus Protocol: Read Word
Unsigned integer—the battery’s designed terminal
voltage in mV
Output:
Units: mV
Unsigned integer—count of total charge removed
from the battery over its life.
Range: 0 to 65,535 mV
Units: cycle
Accuracy: not applicable
Granularity: not applicable
Range: 0 to 65,534 cycles 65,535 indicates battery
has experienced 65,535 or more cycles.
26
bq2060A
SpecificationInfo() (0x1a); [0x1a]
Field
Bits Used
Description: Returns the version number of the Smart
Battery specification the battery pack supports, as well
as voltage and current scaling information in a packed
unsigned integer. Power scaling is the product of the
voltage scaling times the current scaling. The
SpecificationInfo is packed in the following fashion:
(SpecID_H ∗ 0x10 + SpecID_L) + (VScale + IPScale∗
0x10) ∗ 0x100.
Day
0...4
Month
5...8
Year
9...15
Format
5-bit binary
value
4-bit binary
value
7-bit binary
value
Allowable Values
0–31 (corresponds to
date)
1–12 (corresponds to
month number)
0–127 (corresponds to
year biased by 1980)
SerialNumber() (0x1c); [0x1c]
Description: This function is used to return a serial
number. This number, when combined with the
ManufacturerName(), the DeviceName(), and the
ManufactureDate(), uniquely identifies the battery (unsigned int). The bq2060A sets SerialNumber() to the
value programmed in Serial Number EE 0x18–0x19.
The bq2060A VScale (voltage scaling) and IPScale (current scaling) should always be set to zero. The bq2060A
sets SpecificationInfo() to the value programmed in
Specification Information EE 0x14–0x15.
Purpose: The SpecificationInfo() function is used by
the SMBus Host’s power management system to determine what information the Smart Battery can provide.
Purpose: The SerialNumber() function can be used to
identify a particular battery. This may be important in
systems that are powered by multiple batteries where
the system can log information about each battery that
it encounters.
SMBus Protocol: Read Word
Output:
SMBus Protocol: Read Word
Unsigned integer—packed specification number
and scaling information.
Field
Bits
Used
SpecID_L
0...3
Output:
Unsigned integer
Format
Allowable Values
4-bit binary
0–15
value
4-bit binary
0–15
SpecID_H 4...7
value
4-bit binary 0 (multiplies voltage
VScale
8...11
value
by 10^ VScale)
4-bit binary 0 (multiplies current
IPScale 12...15
value
by 10 ^ IPScale)
ManufacturerName() (0x20); [0x20-0x25]
Description: This function returns a character array
containing the battery’s manufacturer’s name. For example, MyBattCo would identify the Smart Battery’s
m a n u f a c t u r er a s M y B a t t C o. T h e b q 2 0 6 0 A s e t s
ManufacturerName() to the value programmed in Manufacturer Name EE 0x20–0x2a.
Purpose: The ManufacturerName() function returns
the name of the Smart Battery’s manufacturer. The
manufacturer’s name can be displayed by the SMBus
Host’s power management system display as both an
identifier and as an advertisement for the manufacturer. The name is also useful as part of the information required to uniquely identify a battery.
ManufactureDate() (0x1b); [0x1b]
Description: This function returns the date the cell
pack was manufactured in a packed integer. The date is
packed in the following fashion: (year-1980) ∗ 512 +
month ∗ 32 + day. The bq2060A sets ManufactureDate()
to the value programmed in Manufacture Date EE
0x16–0x17.
SMBus Protocol: Read Block
Output:
String—character string with maximum length of
11 characters (11+length byte).
Purpose: The ManufactureDate() provides the system
with information that can be used to uniquely identify a
particular battery pack when used in conjunction with
SerialNumber().
DeviceName() (0x21); [0x28-0x2b]
Description: This function returns a character string
that contains the battery’s name. For example, a
DeviceName() of BQ2060A would indicate that the
battery is a model BQ2060A. The bq2060A sets
DeviceName() to the value programmed in Device Name
EE 0x30–0x37.
SMBus Protocol: Read Word
Output:
Unsigned integer—packed date of manufacture.
27
bq2060A
Purpose: The DeviceName() function returns the battery’s name for identification purposes.
Output:
Block data—data that reflects EEPROM programming as assigned by the manufacturer with maximum length of 7 characters (7+length byte).
SMBus Protocol: Read Block
Output:
String—character string with maximum length of 7
characters (7+length byte).
Pack Status and Pack Configuration (0x2f);
[0x2f]
DeviceChemistry() (0x22); [0x30-0x32]
This function returns the Pack Status and Pack Configuration registers. The Pack Status register contains a
number of status bits relating to bq2060A operation.
The Pack Status register is the least significant byte of
the word. The Pack Configuration register is the most
significant byte of the word. The byte reflects how the
bq2060A is configured as defined by the value programmed in Pack Configuration in EE 0x3f.
Description: This function returns a character string
that contains the battery’s chemistry. For example, if
the DeviceChemistry() function returns NiMH, the
battery pack would contain nickel metal hydride cells.
The bq2060A sets DeviceChemistry() to the value
programmed in Device Chemistry EE 0x40–0x44.
Purpose: The DeviceChemistry() function gives cell
chemistry information for use by charging systems. The
bq2060A does not use DeviceChemisty() values for internal charge control or fuel gauging.
The Pack Status Register consists of the following bits:
SMBus Protocol: Read Block
b7
b6
OCE
EDV2
b5
b4
b3
b2
b1
EINT VDQ COK DOK CVOV
b0
CVUV
Output:
OCE
String—character string with maximum length of 4
characters (4+length byte).
Note: The following is a partial list of chemistries and
their expected abbreviations. These abbreviations are
NOT case sensitive.
Lead acid
Lithium ion
Nickel cadmium
Nickel metal hydride
Nickel zinc
Rechargeable alkaline-manganese
Zinc air
The OCE bit indicates that offset cancellation is enabled. The bq2060A sets this bit after VFC offset calibration is complete.
PbAc
LION
NiCd
NiMH
NiZn
RAM
ZnAr
0
Offset calibration is not enabled
1
Offset calibration is enabled
EDV2
The EDV2 bit indicates that Voltage() is less than the
EDV2 threshold.
0
Voltage() > EDV2 threshold (discharging)
1
Voltage() ≤ EDV2 threshold
EINT
ManufacturerData() (0x23); [0x38–0x3a]
The EINT bit indicates that the VFC has detected a
charge or discharge pulse.
Description: This function allows access to the manufacturer data contained in the battery (data). The
bq2060A stores seven critical operating parameters in
this data area.
Purpose: The ManufacturerData() function may be
used to access the manufacturer’s data area. The data
fields of this command reflect the programming of five
critical EEPROM locations and can be used to facilitate
evaluation bq2060A under various programming sets.
The ManufacturerData() function returns the following
information in order: Control Mode, Digital Filter,
Self-Discharge Rate, Battery Low %, Near Full, and the
pending EDV threshold voltage (low byte and high byte.)
0
No charge/discharge activity detected
1
Charge/discharge activity detected.
VDQ
The VDQ bit indicates if the present discharge cycle is
valid for an FCC update.
SMBus Protocol: Read Block
28
0
Discharge cycle is not valid
1
Discharge cycle is valid
bq2060A
COK
EEPROM Programming
The COK bit indicates the status of the CFC pin of the
bq2060A.
0
CFC pin is low
1
CFC pin is high
The following sections describes the function of each
EEPROM location and how the data is to be stored.
Fundamental Parameters
DOK
Sense Resistor Value
The DOK bit indicates the status of the DFC pin of the
bq2060A.
0
DFC pin is low
1
DFC pin is high
Two factors are used to scale the current related measurements. The 16-bit ADC Sense Resistor Gain value
in EE 0x68–0x69 scales Current() to mA. Adjusting
ADC Sense Resistor Gain from its nominal value provides a method to calibrate the current readings for system errors and the sense resistor value (RS) . The nominal value is set by
CVOV
The CVOV bit indicates that a secondary Li-Ion protection limit has been exceeded. It is set if any individual
cell exceeds the programmed high voltage limit, if the
pack voltage exceeds the overvoltage threshold, or if an
over temperature condition occurs. The bit is not latched
and merely reflects the present overvoltage status.
0
No secondary protection limits exceeded
1
A secondary protection limit exceeded
ADC Sense Resistor Gain=
The CVUV bit indicates if any individual cell falls below
the programmed low-voltage limit. The bit applies to
lithium batteries only. The bit is not latched and merely
reflects the present undervoltage status.
All series cells are above the low-voltage limit
1
A series cell is below the low voltage limit
(4)
The 16-bit VFC Sense Resistor Gain in EE 0x6a–0x6b
scales each VFC interrupt to mAh. VFC Sense Resistor
Gain is based on the resistance of the series sense resistor. The following formula computes a nominal or starting value for VFC Sense Resistor Gain from the sense
resistor value.
CVUV
0
625
(Rs)
VFC Sense Resistor Gain=
409.6
(Rs)
(5)
Sense resistor values are limited to the range of 0.00916
to 0.100Ω.
Digital Filter
VCELL4–VCELL1 (0x3c–0x3f); [0x3c–0x3f]
The digital filter threshold, VDF (µV), is set by the
value stored in Digital Filter EE 0x52.
These functions return the calculated voltages in mV at
the VCELL4 through VCELL1 inputs.
Digital Filter =
EEPROM
2250
VDF
(6)
Cell Characteristics
General
Battery Pack Capacity and Voltage
The bq2060A accesses the external EEPROM during a
full reset and when storing historical data. During an
EEPROM access, the VOUT pin becomes active and the
bq2060A uses the ESCL and ESDA pins to communicate
with the EEPROM. The EEPROM stores basic configuration information for use by the bq2060A. The
EEPROM must be programmed correctly for proper
bq2060A operation.
Pack capacity in mAh units is stored in Pack Capacity
EE 0x3a–0x3b. In mAh mode, the bq2060A copies Pack
Capacity to DesignCapacity(). In mWh mode, the
bq2060A multiplies Pack Capacity by Design Voltage EE
0x12–0x13 to calculate DesignCapacity() scaled to
10mWh. Design Voltage is stored in mV.
The initial value for Last Measured Discharge in mAh is
stored in EE 0x38–0x39. Last Measured Discharge is
modified over the course of pack usage to reflect cell
aging under the particular use conditions. The bq2060A
updates Last Measured Discharge in mAh after a
capacity learning cycle. The bq2060A uses the
L a s t M e a s u r e d D i s c h a r g e v a lu e t o c a lc u la t e
FullChargeCapacity() in mAh or 10mWh mode.
Memory Map
Table 9 shows the memory map for the EEPROM. It
also contains example data for a 10 series NiMH and a
3s3p Li-Ion battery pack with a 0.05Ω sense resistor.
29
bq2060A
Table 9. EEPROM Memory Map
EEPROM
Address
0x00
0x02
0x04
0x06
0x07
0x08
0x09
0x0a
0x0c
0x0e
0x10
0x12
0x14
0x16
0x18
0x1a
0x1c
0x1e
0x20
0x21
0x22
0x23
0x24
0x25
0x26
0x27
0x28
0x29
0x2a
0x2b
0x2c
0x2e
0x30
0x31
0x32
0x33
0x34
Name
Check Byte 1
0x01
Remaining Time Alarm
0x03
0x05 Remaining Capacity Alarm
EDV A0 Impedance Age
Factor
EDV TC Cold Impedance
Factor
Misc Options
Safety Overtemperature
Charging Voltage
0x0b
0x0d
Reserved
Cycle Count
0x0f
0x11
Reserved
Design Voltage
0x13
Specification Information
0x15
Manufacture Date
0x17
Serial Number
0x19
Fast-Charging Current
0x1b
Maintenance Charging
0x1d
Current
Pre-Charge Current
0x1f
Manufacturer Name Length
Character 1
Character 2
Character 3
Character 4
Character 5
Character 6
Character 7
Character 8
Character 9
Character 10
Light Discharge Current
0x2d
Reserved
Maximum Overcharge
0x2f
Device Name Length
Character 1
Character 2
Character 3
Character 4
Chemistry
NiMH
Example
Data
MSB LSB
3c
7f
00
0a
01
5e
Li-Ion
Example
Li-Ion, Nickel
Li-Ion, Nickel
Li-Ion, Nickel
15487
10 minutes
350mAh
Li-Ion, Nickel
0
-
00
0
-
00
-
0
-
00
3
-
03
0
0
Li-Ion, Nickel 18000mV
128
Li-Ion, Nickel
0
0
Li-Ion, Nickel 12000mV
Li-Ion, Nickel v1.1/PEC
Li-Ion, Nickel 2/25/99=9817
Li-Ion, Nickel
1
Li-Ion, Nickel
4000mA
46
00
00
00
2e
00
26
00
0f
00
00
50
80
00
00
e0
31
59
01
a0
0
0
12600mV
128
0
0
10800mV
v1.1/PEC
2/25/99=9817
1
3000mA
31
00
00
00
2a
00
26
00
0b
00
00
38
80
00
00
30
31
59
01
b8
Li-Ion, Nickel
200mA
00
c8
0mA
00
00
Li-Ion, Nickel
Li-Ion, Nickel
Li-Ion, Nickel
Li-Ion, Nickel
Li-Ion, Nickel
Li-Ion, Nickel
Li-Ion, Nickel
Li-Ion, Nickel
Li-Ion, Nickel
Li-Ion, Nickel
Li-Ion, Nickel
Li-Ion, Nickel
Li-Ion, Nickel
Li-Ion, Nickel
Li-Ion, Nickel
Li-Ion, Nickel
Li-Ion, Nickel
Li-Ion, Nickel
Li-Ion, Nickel
800mA
9
B
E
N
C
H
M
A
R
Q
0
0
0
200mAh
7
B
Q
2
0
03
00
ff
-
20
09
42
45
4e
43
48
4d
41
52
51
00
00
00
38
07
42
51
32
30
100mA
9
B
E
N
C
H
M
A
R
Q
0
0
0
256mAh
7
B
Q
2
0
00
00
ff
-
64
09
42
45
4e
43
48
4d
41
52
51
00
00
00
00
07
42
51
32
30
15487
10 minutes
400mAh
Data
MSB LSB
3c
7f
00
0a
01
90
(Continued on next page)
Note:
Reserved locations must be set as shown. Locations marked with an * are calibration values that can be
adjusted for maximum accuracy. For these locations the table shows the appropriate default or initial
30
bq2060A
Table 9. EEPROM Memory Map (Continued)
EEPROM
Address
0x35
0x36
0x37
0x38
0x3a
0x3c
0x3e
0x3f
0x40
0x41
0x42
0x43
0x44
0x45
0x46
0x48
0x49
0x39
0x3b
0x3d
0x47
0x4a
0x4b
0x4c
0x4d
0x4e
0x4f
0x50
0x51
0x52
0x53
0x54
0x55
0x56 0x57
0x58 0x59
0x5a 0x5b
Name
Chemistry
NiMH
Example
Character 5
Character 6
Character 7
Last Measured Discharge
Pack Capacity
Cycle Count Threshold
Reserved
Pack Configuration
Device Chemistry Length
Character 1
Character 2
Character 3
Character 4
MaxT DeltaT
Overload Current
Overvoltage Margin
Overcurrent Margin
Reserved
Cell Under/Over Voltage
Fast Charge Termination %
Fully Charged Clear %
Charge Efficiency
Current Taper Threshold
DeltaT Time
Holdoff Time
Current Taper Qual Voltage
Manufacturers Data Length
Control Mode
Digital Filter
Self-Discharge Rate
Battery Low %
Near Full
Reserved
Reserved
Reserved
Li-Ion, Nickel
Li-Ion, Nickel
Li-Ion, Nickel
Li-Ion, Nickel
Li-Ion, Nickel
Li-Ion, Nickel
Li-Ion, Nickel
Li-Ion, Nickel
Li-Ion, Nickel
Li-Ion, Nickel
Li-Ion, Nickel
Li-Ion, Nickel
Li-Ion, Nickel
Li-Ion, Nickel
Li-Ion, Nickel
Li-Ion, Nickel
Nickel
Li-Ion
Li-Ion, Nickel
Li-Ion, Nickel
Li-Ion, Nickel
Li-Ion
Nickel
Nickel
Li-Ion
Li-Ion, Nickel
Li-Ion, Nickel
Li-Ion, Nickel
Li-Ion, Nickel
Li-Ion, Nickel
Li-Ion, Nickel
-
6
0
A
4000mAh
4000mAh
500mAh
0
232
4
N
I
M
H
50C, 3.0
6000mA
0
512mA
0
96%
90%
97%
180s
240s
7
4
50µV
1%
7%
200mAh
0
0
0
Data
MSB LSB
36
30
41
0f
a0
0f
a0
fe
0c
00
e8
04
4e
49
4d
48
c7
17
70
00
20
00
a0
a6
el
07
04
07
04
2d
cb
12
64
00
00
00
Li-Ion
Example
6
0
A
4050mAh
4050mAh
3240mAh
0
246
4
L
I
O
N
50C, 4.6
6000mA
800mV
512mA
118
100%
95%
100%
200mA
128mV
7
4
50µV
0.21%
7%
200mAh
0
0
0
Data
MSB LSB
36
30
41
0f
d2
0f
d2
f3
58
00
f6
04
4c
49
4f
4e
cf
17
70
32
20
76
9c
a1
ff
12
40
07
04
2d
05
12
64
00
00
00
(Continued on next page)
Note:
Reserved locations must be set as shown. Locations marked with an * are calibration values that can be
adjusted for maximum accuracy. For these locations the table shows the appropriate default or initial
setting.
31
bq2060A
Table 9. EEPROM Memory Map (Continued)
EEPROM
Address
0x5c
0x5e
0x60
0x61
0x62
0x5d
0x5f
Description
Chemistry
NiMH
Example
Data
MSB LSB
00
00
00
00
00
00
00
-
Li-Ion, Nickel
Li-Ion, Nickel
Li-Ion, Nickel
Li-Ion, Nickel
Li-Ion
0
0
0
0
0
-
Nickel
0.25%
-
20
-
-
-
Li-Ion
-
-
-
0
-
00
Nickel
96%
-
a0
-
-
-
Li-Ion
Nickel
Li-Ion, Nickel
Li-Ion, Nickel
1%
16 : 1
50
20
d4
0
16 : 1
4e
30
00
20
d4
20
d6
d6
d4
28
2d
11
00
ca
02
40
19
1e
7b
00
eb
14
00
a5
e6
fa
5a
0x66
0x68
0x67
0x69
Reserved
VFC Offset*
VFC Offset*
Temperature Offset*
ADC Offset*
Cell 2 Calibration Factor*
Efficiency Temperature
Compensation
Cell 3 Calibration Factor*
Efficiency Drop Off
Percentage
Cell 4 Calibration Factor*
Efficiency Reduction Rate
ADC Voltage Gain*
ADC Sense Resistor Gain*
0.05Ω
4e
30
0x6a
0x6c
0x6e
0x70
0x72
0x74
0x76
0x6b
0x6d
0x6f
0x71
0x73
0x75
0x77
VFC Sense Resistor Gain*
VOC 25%
VOC 50%
VOC 75%
EDVF/EDV0
EMF/ EDV1
EDV T0 Factor
Li-Ion, Nickel
Li-Ion, Nickel
Li-Ion, Nickel
Li-Ion, Nickel
Li-Ion, Nickel
Li-Ion, Nickel
Li-Ion, Nickel
0.05Ω
11500mV
12500mV
13500mV
9500mV
10000mV
0
20
d3
cf
cb
25
27
00
00
14
2c
44
1c
10
00
0x78
0x79
EDV C1/C0 Factor/EDV2
Li-Ion, Nickel
10500mV
29
04
0x7a
0x7c
0x7e
0x7b
0x7d
0x7f
EDV R0 Factor
EDV R1 Factor
Check Byte 2
Li-Ion, Nickel
Li-Ion, Nickel
Li-Ion, Nickel
0
0
42330
00
a5
00
00
5a
0x63
0x64
0x65
Note:
Li-Ion
Example
0
0
0
0
0
0
0.05Ω
0.05Ω
10550mV
10750mV
11200mV
10265mV
11550
4475
C1 = 0
C0 = 235
5350
250
42330
Data
MSB LSB
00
00
00
00
00
00
00
00
Reserved locations must be set as shown. Locations marked with an * are calibration values that can be adjusted
for maximum accuracy. For these locations the table shows the appropriate default or initial setting.
32
bq2060A
Residual Capacity Factor C1 =RESIDUAL% * 2.56
EDV Thresholds and Near Full Percentage
RESIDUAL % is the desired battery capacity remaining
at EDV0 (RM = 0).
The bq2060A uses three pack voltage thresholds to provide voltage-based warnings of low battery capacity.
The bq2060A uses the values stored in EEPROM for the
EDV0, EDV1, and EDV2 values or calculates the three
thresholds from a base value and the temperature, capacity, and rate adjustment factors stored in EEPROM.
If EDV compensation is disabled then EDV0, EDV1,
andEDV2 are stored directly in mV in EE 0x72–0x73,
EE 0x74–0x75, and EE 0x78–0x79, respectively.
n
R0 ∗ FTZ represents the resistance of the battery as a
function of temperature and capacity.
FTZ = f ( R1 , T0, T, C + C1, TC)
n
For capacity correction at EDV2, Battery Low % EE
0 x 5 4 ca n be s e t at a d e s i r e d s ta te - of - c h a r g e,
STATEOFCHARGE%, in the range of 5 to 20%. Typical
values for STATEOFCHARGE% are 7–12% representing
7 –12% capacity.
n
Battery Low % = STATEOFCHARGE% ∗ 2.56 (7)
The bq2060A updates FCC if a qualified discharge occurs from a near-full threshold to EDV2. The desired
near-full threshold window, NFW (mAh), is programmed
in Near Full in EE 0x55.
Near Full =
NFW
2
n
n
(8)
EDV Discharge Rate and Temperature Compensation
n
If EDV compensation is enabled, the bq2060A calculates
battery voltage to determine EDV0, EDV1, and EDV2
thresholds as a function of battery capacity, temperature, and discharge load. (See Figures 7 and 8.) The general equation for EDV0, EDV1, and EDV2 calculation is
T is the current temperature; C is the battery
capacity relating to EDV0, EDV1, and EDV2; and C1
is the desired residual battery capacity remaining at
EDV0 (RM = 0).
R1 adjusts the variation of impedance with battery
capacity. R1 is programmed in EDV R1 Rate Factor
EE 0x7c–0x7d.
T0 adjusts the variation of impedance with battery
temperature. T0 is programmed in EDV T0 Rate
Factor EE 0x76–0x77.
TC adjusts the variation of impedance for cold
temperature (T < 23°C). TC is programmed in EDV
TC EE 0x07.
(12)
where A0 is the EDV aging factor that is stored in EDV
A0 Factor EE 0x06. It should be set to 0 for most applications.
where
Typical values for the EDV compensation factors for a
Li-Ion 3s3p 18650 pack are
EMF is a no-load battery voltage that is higher than
the highest EDV threshold that is computed. EMF is
programmed in mV in EMF/EDV1 EE 0x74–0x75.
EMF = 11550
T0 = 4475
ILOAD is the current discharge load.
C0 = 235
FBL is the factor that adjusts the EDV voltage for battery capacity and temperature to match the no-load
characteristics of the battery.
FBL = f ( C0, C + C1, T )
R0 is the first order rate dependency factor stored in
EDV R0 Factor EE 0x7a–0x7b.
FCY = f(A0, CycleCount())
EDV0,1,2 = EMF ∗ FBL - |ILOAD| ∗ R0 ∗ FTZ ∗ FCY
n
(11)
FCY is the factor that adjusts for changing cell impedance as the battery pack is cycled:
(9)
n
T is the current temperature in °K
C1 = 0
R0 = 5350
R1 = 250
(10)
A0 = 0
where C (0%, 3%, or Battery Low % for EDV0, EDV1,
and EDV2, respectively) and C0 are the capacity related
EDV adjustment factors. C0 is programmed in the
lower 11 bits of EDV C0 Factor/EDV2 EE 0x78–79.
TC = 3
The graphs in Figures 7 and 8 show the calculated
EDV0, EDV1, and EDV2 thresholds versus capacity using the typical compensation values for different
temperatures and loads for a Li-Ion 3s3p 18650 pack.
The compensation values vary widely for different cell
The Residual Capacity Factor is stored in the upper 5
bits of EE 0x78–0x79.
33
bq2060A
Charge Efficiency = 10 ∗ (EFF% - 74.5)
types and manufacturers and must be matched exactly
to the unique characteristics for optimal performance.
where
Overload Current Threshold
74.5 ≤ EFF% ≤ 100
The Overload Current threshold is a 16-bit value stored
in EE 0x46-0x47 in mA units.
ERR% is encoded in Efficiency Reduction Rate EE 0x65
according to the following equation:
Midrange Capacity Corrections
Efficiency Reduction Rate =
Three voltage-based thresholds, VOC25 EE 0x6c–0x6d,
VOC50 EE 0x6e–0x6f, and VOC75 EE 0x70–0x71, are
u se d t o t e s t t he ac c ur a c y o f t he R M b a s ed on
open-circuit pack voltages. These thresholds are stored
in the EEPROM in 2’s complement of voltage in mV.
The values represent the open-circuit battery voltage at
which the battery capacity should correspond to the associated state of charge for each threshold.
(16)
0 ≤ ERR% ≤ 3.19
The Efficiency Drop Off Percentage is stored in 2’s complement of percent.
The bq2060A also adjusts the efficiency factors for temperature. TEFF% defines the percent efficiency reduction per degree C over 25°C. TEFF% is encoded in Efficiency Temperature Compensation EE 0x63 according to
the following equation
The nominal self-discharge rate, %PERDAY (% per day),
is programmed in an 8-bit value Self-Discharge Rate EE
0x53 by the following relation:
(17)
TEFF% *1.6
Efficiency Temperature Compensation =
0.0125
(13)
where
0 ≤ TEFF% ≤1.99
Light Load Current
The bq2060A applies all four charge-compensation factors when the CHEM bit in Pack Configuration is not
set denoting a nickel pack.
The amount of light load current in mA, ILEAK, used
for compensation is stored in Light Discharge Current in
EE 0x2b as follows:
Light Discharge Current =
ERR%
0.0125
where
Self-Discharge Rate
æ
52.73 ö
÷
Self - Discharge Rate = 256 -ç
è %PERDAY ø
(15)
ILEAK * 1024
45
(18)
(14)
Effective Charge Efficiency Reduction (nickel only)
= ERR%[RSOC() – EFF%] + TEFF%[T(°C) – 25]
ILEAK is between 0.044 and 11.2mA.
where
Charge Efficiency
RSOC() ≥ EFF% and T ≥ 25°C
The bq2060A uses four charge-efficiency factors to compensate for charge acceptance. These factors are coded
in Charge Efficiency, Efficiency Reduction Rate, Efficiency Drop Off Percentage, and Efficiency Temperature
Compensation.
If CHEM is set denoting a Li-Ion pack, the bq2060A applies only the value coded in High Charge Efficiency and
makes no other adjustments for charge acceptance.
Charge Limits and Termination
Techniques
The bq2060A applies the efficiency factor, EFF%, when
RelativeStateOfCharge() is less than the value coded in
Efficiency Drop Off Percentage EE 0x64. When
RelativeStateOfCharge() is greater than or equal to the
value coded in Efficiency Drop Off Percentage, EFF%
and ERR% determine the charge efficiency rate. ERR%
defines the percent efficiency reduction per percentage
point of RelativeStateOfCharge() over Efficiency Drop
Off Percentage. EFF% is encoded in High Charge
Efficiency EE 0x4d according to the following equation:
Charging Voltage
The 16-bit value, Charging Voltage EE 0x0a-0x0b programs the ChargingVoltage() value broadcast to a Smart
Charger. It is also sets the base value for determining
overvoltage conditions during charging and voltage compliance during a constant-voltage charging methodology.
It is stored in mV.
34
bq2060A
Battery Low % =7%, Temperature = 35 C
Battery Low %= 7%, Load = 500mA
11500
11500
11000
11000
EDV2
EDV2
10500
EDV1
EDV1
Voltage (mV)
Voltage (mV)
10500
10000
9500
9000
9500
9000
35C/500mA
35C/1A
35C/2A
8500
45C/500mA
8500
10000
8000
20C/500mA
8000
7500
7500
7000
EDV0
10
9
8
7
6
5
4
3
2
1
0
10
9
8
6
5
4
3
2
1
0
Figure 8. EDV Calculations vs. Capacity
for Various Loads
Figure 7. EDV Calculations vs. Capacity
for Various Temperatures
Fast Charging Current, Maintenance Charging Current,
and Pre-Charge Current are stored in mA.
Overvoltage
The 8-bit value, Overvoltage Margin EE 0x48, sets the
limit over ChargingVoltage() that is to be considered as
an overvoltage charge-suspension condition. The voltage in mV above the ChargingVoltage(), VOVM, that
should trigger a charge suspend is encoded in
Overvoltage Margin as follows:
Overvoltage Margin=
7
% Capacity
% Capacity
VOVM
16
Charge Suspension
During charge, the bq2060A compares the current to the
ChargingCurrent() plus the value IOIM. If the pack is
charged at a current above the ChargingCurrent() plus
IOIM, the bq2060A sets ChargingCurrent() to zero to
stop charging. IOIM is programmed in the EEPROM
value, Overcurrent Margin, encoded as follows:
(19)
VOVM is between 0 and 4080mV.
Overcurrent Margin=
Charging Current
IOIM
16
(20)
Overcurrent Margin EE 0x49 may be used to program
IOIM values of 0 to 4080mA in 16mA steps.
ChargingCurrent() values are either broadcast to a
Level 2 Smart Battery Charger or read from the
bq2060A by a Level 3 Smart Battery Charger. The
bq2060A sets the value of ChargingCurrent(), depending
on the charge requirements and charge conditions of the
pack.
The desired temperature threshold for charge suspension, MAXTEMP, may be programmed between 45°C
and 69°C in 1.6°C steps. Charge-suspension temperature is increased by 16° above the programmed value of
bit 5 in Miscellaneous Option EE 0x08 is set. MaxT
DeltaT EE 0x45 (most significant nibble) is stored in a
4-bit value as shown:
When fast charge is allowed, the bq2060A sets
ChargingCurrent() to the rate programmed in Fast
Charging Current EE 0x1a-0x1b.
é 69 - MAXTEMP ù
MaxT =ê
ú
ë
û
1.6
When fast charge terminates, the bq2060A sets
ChargingCurrent() to zero and then to the Maintenance
Charging Current EE 0x1c-0x1d when the termination
condition ceases.
(21)
The bq2060A suspends fast charge when fast charge
continues past full by the amount programmed in Maximum Overcharge EE 0x2e-0x2f. Maximum Overcharge
is programmed in 2s complement form of charge in
mAh.
When Voltage() is less than EDV0, the bq2060A sets
ChargingCurrent() to Pre-charge Current EE 0x1e-0x1f.
Typically this rate is larger than the maintenance rate
to charge a deeply depleted pack up to the point where it
may be fast charged.
35
bq2060A
FULLY_CHARGED Bit Clear Threshold
Hold-off
Time
00
01
02
03
04
05
06
07
The bq2060A clears the FULLY_CHARGED bit in
BatteryStatus() when RelativeStateOfCharge() reaches
the value, Fully Charged Clear % EE 0x4c. Fully
Charged Clear % is an 8-bit value and is stored as a 2’s
complement of percent.
Fast Charge Termination Percentage
The bq2060A sets RM to a percentage of FCC on charge
termination if the CSYNC bit is set in the Pack Configuration register. The percentage of FCC is stored in Fast
Charge Termination % in EE 0x4b. The value is stored
in 2’s complement of percent.
∆T/Dt Rate Programming
The ∆T portion of the ∆T/∆t rate is programmed in
DeltaT, the low nibble of MaxT DeltaT EE 0x45 (least
significant nibble). The ∆t portion is programmed in
DeltaT Time EE 0x4e.
D(°C)
1.6
1.8
2.0
2.2
2.4
2.6
2.8
3.0
3.2
3.4
3.6
3.8
4.0
4.2
4.4
4.6
DeltaT_Time
00
01
02
03
04
05
06
07
08
09
0a
0b
0c
0d
0e
0f
Hold-off
Time (s)
160
140
120
100
80
60
40
20
Two factors in the EEPROM set the current taper termination for Li-Ion battery packs. The two coded locations
are Current Taper Qual Voltage EE 0x4f and Current
Taper Threshold EE 0x4e. Current taper termination occurs during charging when the pack voltage is above the
charging voltage minus CELLV (mV) and the charging
current is below the threshold coded in Current Taper
Threshold for at least 80s.
Cycle Count Threshold 0x3c–0x3d sets the number of
mAh that must be removed from the battery to increment CycleCount(). Cycle Count Threshold is a 16-bit
value stored in 2’s complement of charge in mAh.
DeltaT
0
1
2
3
4
5
6
7
8
9
a
b
c
d
e
f
Hold-off
Time
08
09
0a
0b
0c
0d
0e
0f
Current Taper Termination Characteristics
Cycle Count Threshold
[DeltaT * 2 + 16] / 10 é ° Cù
∆T/∆t =
ë sú
û
[320 - DeltaT Time* 20]ê
Hold-off
Time (s)
320
300
280
260
240
220
200
180
Current Taper Qual Voltage =
Current Taper Threshold =
(22)
CELLV
2
(23)
RS* i
0.5625
(24)
where i = the desired current termination threshold in
mA, and RS = VFC sense resistor in ohms.
t (s)
320
300
280
260
240
220
200
180
160
140
120
100
80
60
40
20
Pack Options
Pack Configuration
Pack Configuration EE 0x3f contains bit-programmable
features.
b7
b6
DMODE SEAL
b5
b4
b3
b2
b1
b0
CSYNC
CEDV
VCOR
CHEM
LCC1
LCC0
DMODE
The DMODE bit determines whether the LED outputs
will
indicate
AbsoluteStateOfCharge()
or
RelativeStateOfCharge()
DT/Dt Hold-off Timer Programming
The hold-off timer is programmed in the lower nibble of
Holdoff Time EE 0x4f. The hold-off time is 320s minus
20 times the Holdoff Time value.
36
0
LEDs reflect AbsoluteStateOfCharge()
1
LEDs reflect RelativeStateOfCharge()
bq2060A
SEAL
LCC0 and LCC1
The SEAL bit determines the SMBus access state of the
bq2060A on reset
The LCC0 and LCC1 bits configure the cell voltage inputs (VCELL1–4).
0
SMBus commands (0x00–0xff) are accessible for
both read and write.
1
SMBus read access is limited to commands
(0x05–0x1c) and (0x20–0x23). SMBus read/write
access is limited to commands (0x00–0x04), (0x2f),
and (0x3c–0x3f).
No. of Series
Cells
NA
2
3
CSYNC
In usual operation of the bq2060A, the CSYNC bit is set
so that the coulomb counter is adjusted when a fast
charge termination is detected. In some applications, especially those where an externally controlled charger is
used, it may be desirable NOT to adjust the coulomb
counter. In these cases the CSYNC bit should be cleared.
0
The bq2060A does not alter RM at the time of a
valid charge termination.
1
The bq2060A updates RM with a programmed percentage of FCC at a valid charge termination.
4
For Li-Ion packs with individual measurements, LCC0
and LCC1 define the number of series elements and
their voltage measurement inputs. In each case (2, 3, or
4), the bq2060A uses the highest numbered cell voltage
input to measure the pack voltage measurement as returned with Voltage(). For nickel chemistries or Li-Ion
without single-cell measurements, LCC0 and LCC1
must be set to 00. VCELL4 is the pack voltage input for
this programming.
CEDV
The CEDV bit determines whether the bq2060A implements automatic EDV compensation to calculate the
EDV0, EDV1 and EDV2 thresholds base on rate, temperature, and capacity. If reset, the bq2060A uses the
fixed values programmed in EEPROM for EDV0, EDV1
and EDV2. If set the bq2060A calculates EDV0, EDV1
and EDV2.
0
EDV compensation disabled
1
EDV compensation enabled
Remaining Time and Capacity Alarms
Remaining Time Alarm in EE 0x02–0x03 and Remaining Capacity Alarm in 0x04–0x05set the alarm
thresholds used in the SMBus command codes 0x01 and
0x02, respectively. Remaining Time Alarm is stored in
minutes and Remaining Capacity Alarm in mAh.
Secondary Protection Limits for Li-Ion
VCOR
The cell undervoltage (VUV) and overvoltage (VOV) limits
are programmed in Cell Undervoltage/Over Voltage EE
0x4a according to the equations:
The VCOR bit enables the midrange voltage correction
algorithm. When set, the bq2060A compares the pack
voltage to RM and may adjust RM according to the values programmed in VOC25, VOC50, and VOC75.
0
Midrange corrections disabled
1
Midrange corrections enabled
CHEM
The CHEM bit configures the bq2060A for nickel packs
(NiCd or NiMH) or Li-Ion packs. When set the bq2060A
employs the configuration parameters in EEPROM designated for Li-Ion. When not set, the bq2060A employs
the configuration parameters designated for nickel.
0
The bq2060A uses nickel configuration parameters.
1
The bq2060A uses Li-Ion configuration parameters.
Cell Voltage
LCC1 LCC0
Inputs
00
VCELL4 = Cell Stack
VCELL1 = Cell 1
01
VCELL2 = Cell 2
VCELL1 = Cell 1
10
VCELL2 = Cell 2
VCELL3 = Cell 3
VCELL1 = Cell 1
VCELL2 = Cell 2
11
VCELL3 = Cell 3
VCELL4 = Cell 4
37
Cell Undervoltage/Overvoltage (lower) =
VOV - 4096
32
(25)
Cell Undervoltage/Overvoltage (upper) =
VUV - 2048
64
(26)
bq2060A
Cell Under/Over
Voltage
(upper nibble)
0
1
2
3
4
5
6
7
8
9
a
b
c
d
e
f
VUV
(mV)
2048
2112
2176
2240
2304
2368
2432
2496
2560
2624
2688
2752
2816
2880
2944
3008
Cell Under/Over
Voltage
(lower nibble)
0
1
2
3
4
5
6
7
8
9
a
b
c
d
e
f
HIT
VOV
(mV)
4096
4128
4160
4192
4224
4256
4288
4320
4352
4384
4416
4448
4480
4512
4544
4576
The HIT bit controls the available temperature range
for maximum temperature.
0
Maximum temperature set in normal 45–85°C
range
1
Maximum temperature set in elevated 61–85°C
range
Cycle Count Initialization
Cycle Count EE 0x0e–0x0f stores the initial value for
the CycleCount() function. It should be programmed to
0x0000.
Control Modes
Control Mode EE0x51 contains additional bit programmable features.
b7
NDF
S afety O ve r t e m p e r a t ur e E E 0 x 0 9 s et s S a f et y
Overtemperature Threshold (SOT) level for the CFC pin.
It can be programmed for a threshold of 69° to 85°C.
This range is increased by 16° if Miscellaneous Options
bit 5 = 1.
b6
-
b5
HPE
b4
CPE
b3
LED
b2
SC
b1
-
b0
SM
NDF
The NDF bit disables the digital filter during discharge
if the SMBC and SMBD lines are high.
SafetyOvertemperature = (94.5 - SOT ) * 10
if Miscellaneous Options bit 5 = 0.
SafetyOvertemperature = (110.5 - SOT ) * 10
0
Digital filter enabled all the time
1
Digital filter disabled if SMBC and SMBD are high
HPE
if Miscellaneous Options bit 5 = 1.
The HPE bit enables/disables PEC transmissions to the
Smart Battery host for master mode alarm messages.
Miscellaneous Options
M iscella ne o us O p t i o ns E E 0 x 0 8 c on t a in s
bit-programmable options. Bits 0–4 should be programmed to zero.
b7
NE1
b6
SOT
b5
HIT
b4
0
b3
0
b2
0
b1
0
0
No PEC byte on alarm warning to host
1
PEC byte on alarm warning to host
CPE
b0
0
The CPE bit enables/disables PEC transmissions to the
Smart Battery Charger for master mode alarm messages.
NE1
The NE1 bit disables the EDV1 threshold.
0
No PEC byte on broadcasts to charger
PEC byte on broadcasts to charger
0
EDV1 enabled
1
1
EDV1 disabled
LED
SOT
The LED bit configures the bq2060A for 4 or 5 LED indication
The SOT bit controls override of the CFC pin for Safety
Overtemperature threshold.
0
CFC control with overvoltage, maximum temperature, and safety overtemperature.
1
CFC control; only with safety overtemperature.
38
0
Selects the 5 LED indication mode
1
Selects the 4 LED indication mode
bq2060A
The bq2060A compute the node voltages as follows:
SC
(27)
The SC bit enables learning cycle optimization for a
Smart Charger or independent charge
0
Learning cycle optimized for independent charger
1
Learning cycle optimized for Smart Charger
é VCELL1*32768
ù é ADC Voltage Gain ù
Vn1=ê
+ ADC Offsetú*ê
ú
û
ë
ûë
65536
1250
(28)
é VCELL2*32768
ù
Vn2=ê
+ ADC Offsetú*
ë
û
1250
SM
The SM bit enables/disables master mode broadcasts by
the bq2060A
0
Broadcasts to host and charger enabled
1
Broadcasts to host and charger disabled
é ADC Voltage Gain + 8* (Cell 2 CalibrationFactor) ù
ê
ú
ë
û
65536
(29)
é VCELL3*32768
ù
Vn3=ê
+ ADC Offsetú *
ë
û
1250
I f t h e S M bi t i s s e t , m o d i f i c a ti o ns t o b it s in
BatteryMode() will not re-enable broadcasts.
[ ADC Voltage Gain + 8* (Cell
3 CalibrationFactor) ]*
é
2 ù
ê
ë 65536ú
û
Measurement Calibration
ADC
(30)
é VCELL4*32768
ù
Vn4=ê
+ ADC Offsetú*
ë
û
1250
To describe how the bq2060A calculates reported battery
and individual cell voltages, the following abbreviations
and designations are used:
[ ADC Voltage Gain + 8* (Cell 4 CalibrationFactor)]*
VCELL 1–4 = voltages at the input pins of the
bq2060A
é
ê
ë
VCELL1–4 = reported cell voltages
2 ù
ú
65536û
Note: With LCC1-LCC0 = 00, Cell 4 Calibration
Factor = 0.
Vnl–4 = voltages at the different series nodes in the
battery
ADC Offset adjusts the ADC reading for voltage and current measurements. ADC Offset is a signed 8-bit value
that cancels offset present in the circuit with no potential or current flow. ADC Offset is typically set between
-20 and 20.
Voltage() = reported battery voltage
Vsr = voltage across the sense resistor
The reported voltages measurements, Voltage() and
VCELL1–4, may be calibrated by adjusting five 8- or
16-bit registers in EEPROM: ADC Offset in EE0x62,
ADC Voltage Gain in EE 0x66–0x67, Cell 2 Calibration
Factor in EE 0x63, Cell 3 Calibration Factor in EE 0x64,
and Cell 4 Calibration Factor in EE 0x65.
The bq2060A uses the computed node voltages to calculate the reported voltages. It does not compute reported
cell voltages greater than the selected number of nodes.
If no individual cell voltages are to be measured,
LCC1–LCC0 should be set to 00 and the top of the battery stack should be connected to a voltage divider to
the VCELL4 input.
The bq2060A first computes the node voltages Vnl, Vn2,
Vn3, and Vn4. The node voltages are inputs to the voltage dividers to the VCELL1 through VCELL4 input pins
of the bq2060A. The bq2060A computes node voltages to
calculate the five reported voltages by the bq2060A:
Voltage(), VCELL1, VCELL2, VCELL3, and VCELL4.
The bq2060A computes the reported voltages as follows:
Voltage() = Vn4 (LCC1–LCC0 = 11 or 00) - Vsr
Voltage() = Vn3 (LCC1–LCC0 = 10) - Vsr
An ADC Voltage Gain factor of 20,000 is the nominal
value when using the recommended cell-voltage division
ratios of 16:1 on the VCELL4 and VCELL3 inputs and
8:1 on the VCELL2 and VCELL1 inputs. The bq2060A
subtracts the voltage across the sense resistor from the
measurements so that the reported voltages reflect the
cell-stack voltages only.
Voltage() = Vn2 (LCC1–LCC0 = 01) - Vsr
VCELL4 = Vn4 - Vn3
VCELL3 = Vn3 - Vn2
VCELL2 = Vn2 - Vn1
VCELL1 = Vn1 - Vsr
39
bq2060A
Current
Constants and String Data
The bq2060A scales Current() to mA units by the 16-bit
value ADC Sense Resistor Gain in EE 0x68–0x69.
Adjusting ADC Sense Resistor Gain from its nominal
value provides a method to calibrate the current readings for variances in the ADC gain, internal voltage reference, and sense resistor value. The bq2060A calculates
Current() by
EEPROM Constants
Check/Byte 1 EE 0x00–0x01 and Check Byte 2 EE
0x7e–0x7f must be programmed to 0x3c7f and 0xa55a,
respectively.
Specification Information
Specification Information EE 0x14–0x15 stores the default value for the SpecificationInfo() function. It is
stored in EEPROM in the same format as the data returned by the SepcificationInfo().
(31)
Current() =
[(ADC Reading + ADC Offset)* ADC Sense Resistor Gain]
16,384
Manufacture Date
Manufacture Date EE 0x16–0x17 stores the default
value for the ManufactureDate() function. It is stored in
EEPROM in the same format as the data returned by
the ManufactureDate().
The nominal value for ADC Sense Resistor Gain is given
by equation (6).
VFC
Serial Number
To calibrate the coulomb counting measurement for VFC
gain errors and sense resistor tolerance, the value of
VFC Sense Resistor Gain EE 0x6a-0x6b may be adjusted
from its nominal value.
Serial Number EE 0x18–0x19 stores the default value
for the SerialNumber() function. It is stored in
EEPROM in the same format as the data returned by
the SerialNumber().
The nominal value of VFC Sense Resistor Gain is given
by equation (5).
Manufacturer Name Data
The bq2060A VFC circuit can introduce a signal opposite
in sign from that of the inherent device and circuit offset
to cancel this error. The offset calibration routine is initiated with commands to ManufacturerAccess().
Manufacturer Name Length EE 0x20 stores the length
of t h e d es ir ed s t r in g t h a t is r et u r n ed b y t h e
ManufacturerName() function. Locations EE 0x21–0x2a
store the characters for ManufacturerName() in ASCII
code.Device Name Data
The bq2060A calculates the offset with the calibration
routine and stores the calibration value using the least
21 bits of VFC Offset in EE 0x5e–0x60.
Device Name Length EE 0x30 stores the length of the
desired string that is returned by the DeviceName()
function. Locations EE 0x31–0x37 store the characters
for DeviceName() in ASCII code.
The least 20 bits store the offset calibration value
(OCV). The sign of the offset calibration value is positive
if the 21st bit is 0.
0.6V
OCV =
VFCuOffset19 – 0
Device Chemistry Data
(32)
Device Chemistry Length EE 0x40 stores the length of
t h e d es ir ed s t r in g t h a t is r et u r n ed b y t h e
DeviceChemistry() function. Locations EE 0x41–0x44
store the characters for DeviceChemistry() in ASCII
code.
Temperature
The bq2060A uses Temperature Offset in EE 0x61 to calibrate the Temperature() function for offset. The required
offset adjustment, TOFF (C), sets Temperature Offset according to the equation
Temperature Offset = TOFF * 10
Manufacturers Data Length
Manufacturers Data Length EE 0x50 stores the length
of the desired number of bytes that is returned by the
ManufacturersData() function. It should be set to 7.
(33)
where
-12.8 ≤ TOFF ≤12.7
40
bq2060A
Absolute Maximum Ratings
Symbol
Parameter
Minimum
Maximum
Unit
VCC—Supply voltage
Relative to VSS
-0.3
+6.0
V
VIN–All other pins
Relative to VSS
-0.3
+6.0
V
TOPR
Operating
temperature
-20
+70
°C
Notes
Commercial
Note: Permanent device damage may occur if Absolute Maximum Ratings are exceeded. Functional operation
should be limited to the Recommended DC Operating Conditions detailed in this data sheet. Exposure to
conditions beyond the operational limits for extended periods of time may affect device reliability.
DC Electrical Characteristics (VCC = 2.7–3.7V, TOPR = -20–70°C, Unless Otherwise Noted)
Symbol
Parameter
Conditions
VCC
Supply voltage
ICC
Operating current
VOUT inactive
Minimum Typical
2.7
ISLP
Low-power storage mode current
1.5V < VCC < 3.7V
ILVOUT
VOUT leakage current
VOUT inactive
-0.2
IVOUT
VOUT source current
VOUT active,
VOUT = VCC - 0.6V
-5.0
VOLS
Output voltage low: LED1–LED5, CFC,
DFC
IOLS = 5mA
Output voltage low: THON, CVON
IOLS = 5mA
Maximum
Unit
3.3
3.7
V
180
235
µA
10
µA
0.2
µA
5
mA
0.4
V
0.36
V
Input voltage low DISP
-0.3
0.8
V
VIH
Input voltage high DISP
2.0
VCC + 0.3
V
VOL
Output voltage low SMBC, SMBD,
HDQ16, ESCL, ESDA
0.4
V
VILS
Input voltage low SMBC, SMBD,
HDQ16, ESCL, ESDA
-0.3
0.8
V
VIHS
Input voltage high SMBC, SMBD,
HDQ16, ESCL, ESDA
1.7
6.0
V
VAI
Input voltage range VCELL1–4, TS,
SRC
VSS - 0.3
1.25
V
50
nA
VIL
IRB
RBI data-retention input current
VRBI
RBI data-retention voltage
ZAI1
Input impedance: SR1, SR2
ZAI2
Input impedance: VCELL1–4, TS, SRC
Note:
IOL = 1.0mA
VRBI > 3.0V, VCC < 2.0V
10
1.3
V
0–1.25V
10
MΩ
0–1.25V
5
MΩ
ZAI specifications are reference numbers based on process data.
41
bq2060A
VFC Characteristics (VCC = 3.1–3.5V, TOPR = 0–70°C Unless Otherwise Noted))
Symbol
Parameter
Conditions
VSR
Input voltage range, VSR2
and VSR1
VSR = VSR2 – VSR1
–0.25
VSROS
VSR input offset
VSR2 = VSR1, autocorrection
disabled
–250
VSRCOS
Calibrated offset
RMVCO
Supply voltage gain
coefficient (see Note)
Temperature gain
coefficient (see note)
–50
–16
VCC = 3.3V
Slope for TOPR = –20 to 70°C
RMTCO
Minimum Typical Maximum
0.8
–0.09
Unit
+0.25
V
250
µV
+16
µV
1.2
%/V
+0.09
%/°C
Total Deviation TOPR = –20 to 70°C
–1.6
0.1
%
Slope for TOPR = –0 to 50°C
–0.05
+0.05
%/°C
Total Deviation TOPR = –0 to 50°C
–0.6
0.1
%
0.21
%
Integral nonlinearity
TOPR = 0–50C
INL
error
Note: RMTCO total deviation is from the nominal gain at 25°C.
REG Characteristics (TOPR = -20–70°C)
Symbol
Parameter
VRO
REG controlled output voltage
IREG
REG output current
Conditions
JFET: Rds(on) < 150Ω
Vgs (off) < –3.0V @ 10µA
Minimum Typical
3.1
1.0
42
3.3
Maximum
Unit
3.5
V
µA
bq2060A
SMBus AC Specifications (VCC = 2.7–3.7V, TOPR = -20–70°C, Unless Otherwise Noted)
Symbol
Parameter
Conditions
Min.
FSMB
SMBus operating frequency
Slave mode, SMBC 50% duty cycle
10
SMBus master clock frequency
Master mode, no clock low slave
extend
FMAS
THD:STA
TSU:STA
TSU:STO
Bus free time between start and
stop
Hold time after (repeated) start
Repeated start setup time
Stop setup time
THD:DAT
Data hold time
TSU:DAT
TTIMEOUT
TLOW
THIGH
Data setup time
Error signal/detect
Clock low period
Clock high period
Cumulative clock low slave
extend time
Cumulative clock low master
extend time
TBUF
TLOW:SEXT
TLOW:MEXT
Notes:
Typ.
Max.
Unit
100
kHz
51.2
kHz
4.7
µs
4.0
4.7
4.0
0
300
250
25
4.7
4.0
50
µs
µs
µs
ns
ns
ns
ms
µs
µs
See Note 3
25
ms
See Note 4
10
ms
Receive mode
Transmit mode
See Note 1
See Note 2
35
1. The bq2060A will time out when any clock low exceeds TTIMEOUT.
2. THIGH Max. is minimum bus idle time. SMBC = SMBD = 1 for t > 50µs will cause reset of any
transaction involving bq2060A that is in progress.
3. TLOW:SEXT is the cumulative time a slave device is allowed to extend the clock cycles in one message
from initial start to the stop. The bq2060A typically extends the clock only 20µs as a slave in the read
byte or write byte protocol.
4. TLOW:MEXT is the cumulative time a master device is allowed to extend the clock cycles in one message from initial start to the stop. The bq2060A typically extends the clock only 20µs as a master in
the read byte or write byte protocol.
HDQ16 AC Specifications (VCC = 2.7–3.7V, TOPR = -20–70 C, Unless Otherwise Noted)
Symbol
Parameter
Min.
Typ.
Max.
tCYCH
Cycle time, host to bq2060A (write)
Conditions
190
-
-
Unit
µs
tCYCB
Cycle time, bq2060A to host (read)
190
205
250
µs
tSTRH
Start hold time, host to bq2060A
(write)
5
-
-
ns
tSTRB
Start hold time, bq2060A to host (read)
32
-
-
µs
tDSU
Data setup time
-
-
50
µs
tDSUB
Data setup time
-
-
50
µs
tDH
Data hold time
100
-
-
µs
tDV
Data valid time
80
-
-
µs
tSSU
Stop setup time
-
-
145
µs
tSSUB
Stop setup time
-
-
145
µs
tRSPS
Response time, bq2060A to host
190
-
320
µs
tB
Break time
190
-
-
µs
tBR
Break recovery time
40
-
-
µs
43
bq2060A
SMBus Timing Data
HDQ16 Break Timing
tBR
tB
TD201803.eps
HDQ16 Host to bq2060A
Write "1"
Write "0"
tSTRH
tDSU
tDH
tSSU
tCYCH
HDQ16 bq2060A to Host
Read "1"
Read "0"
tSTRB
tDSUB
tDV
tSSUB
tCYCB
TD201805.eps
44
bq2060A
Ordering Information
bq2060A-E619 DBQ
Tape and Reel
blank = tubes
R = tape and reel
Package Option:
DBQ = 28-pin SSOP
Device:
bq2060A SBS v1.1-Compliant Gas Gauge IC
45
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Copyright © 2002, Texas Instruments Incorporated
46