Texas Instruments bq27220 Product manual

BQ27220
Technical Reference Manual
Literature Number: SLUUBD4A
APRIL 2016 – REVISED NOVEMBER 2022

Read This First...........................................................................................................................................................................7
1.1 About This Manual............................................................................................................................................................. 7
1.2 Formatting conventions used in this document:.................................................................................................................7
1.3 Related Documentation from Texas Instruments............................................................................................................... 7
1.4 Trademarks........................................................................................................................................................................ 7
1 General Description................................................................................................................................................................9
1.1 Gas Gauging...................................................................................................................................................................... 9
1.1.1 CEDV Gas Gauging Operational Overview...............................................................................................................10
1.1.2 Main Fuel Gauge Registers.......................................................................................................................................10
1.1.3 Capacity Learning (FCC Update) and Qualified Discharge....................................................................................... 11
1.1.4 End-of-Discharge Thresholds and Capacity Correction............................................................................................ 12
1.1.5 EDV Discharge Rate and Temperature Compensation............................................................................................. 12
1.1.6 EDV Age Factor.........................................................................................................................................................13
1.1.7 Self-Discharge........................................................................................................................................................... 13
1.1.8 Battery Electronic Load Compensation..................................................................................................................... 14
1.1.9 CEDV Configuration.................................................................................................................................................. 14
1.1.10 Initial Battery Capacity at Device Reset.................................................................................................................. 14
1.1.11 Fuel Gauge Operating Modes..................................................................................................................................15
1.1.12 Qmax....................................................................................................................................................................... 15
1.1.13 CEDV Smoothing.................................................................................................................................................... 15
2 Standard Data Commands...................................................................................................................................................17
2.1 Standard Commands....................................................................................................................................................... 17
2.2 Control()/CONTROL_STATUS(): 0x00 and 0x01............................................................................................................. 18
2.2.1 CONTROL_STATUS: 0x0000....................................................................................................................................19
2.2.2 DEVICE_NUMBER: 0x0001......................................................................................................................................19
2.2.3 FW_VERSION: 0x0002............................................................................................................................................. 19
2.2.4 HW_VERSION: 0x0003.............................................................................................................................................20
2.2.5 BOARD_OFFSET: 0x0009........................................................................................................................................ 20
2.2.6 CC_OFFSET: 0x000A............................................................................................................................................... 20
2.2.7 CC_OFFSET_SAVE: 0x000B....................................................................................................................................20
2.2.8 OCV_CMD: 0x000C.................................................................................................................................................. 20
2.2.9 BAT_INSERT: 0x000D...............................................................................................................................................20
2.2.10 BAT_REMOVE: 0x000E.......................................................................................................................................... 20
2.2.11 SET_SNOOZE: 0x0013...........................................................................................................................................20
2.2.12 CLEAR_SNOOZE: 0x0014......................................................................................................................................20
2.2.13 SET_PROFILE_1/2/3/4/5/6: 0x0015–0x001A......................................................................................................... 20
2.2.14 CAL_TOGGLE: 0x002D.......................................................................................................................................... 21
2.2.15 SEALED: 0x0030.....................................................................................................................................................21
2.2.16 RESET: 0x0041....................................................................................................................................................... 21
2.2.17 OPERATION_STATUS: 0x0054.............................................................................................................................. 21
2.2.18 GaugingStatus: 0x0056........................................................................................................................................... 21
2.2.19 EXIT_ CAL: 0x0080.................................................................................................................................................21
2.2.20 ENTER_CAL: 0x0081..............................................................................................................................................21
2.2.21 ENTER_CFG_UPDATE: 0x0090.............................................................................................................................22
2.2.22 EXIT_CFG_UPDATE_REINIT: 0x0091....................................................................................................................22
2.2.23 EXIT_CFG_UPDATE: 0x0092.................................................................................................................................22
2.2.24 ENTER_ROM: 0x0F00............................................................................................................................................ 22
2.3 AtRate(): 0x02 and 0x03.................................................................................................................................................. 22
2.4 AtRateTimeToEmpty(): 0x04 and 0x05............................................................................................................................ 22
2.5 Temperature(): 0x06 and 0x07......................................................................................................................................... 22
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2.6 Voltage(): 0x08 and 0x09................................................................................................................................................. 22
2.7 BatteryStatus(): 0x0A and 0x0B.......................................................................................................................................23
2.8 Current(): 0x0C and 0x0D................................................................................................................................................ 23
2.9 RemainingCapacity(): 0x10 and 0x11.............................................................................................................................. 23
2.10 FullChargeCapacity(): 0x12 and 0x13............................................................................................................................23
2.11 TimeToEmpty(): 0x16 and 0x17......................................................................................................................................23
2.12 TimeToFull(): 0x18 and 0x19..........................................................................................................................................23
2.13 StandbyCurrent(): 0x1A and 0x1B................................................................................................................................. 24
2.14 StandbyTimeToEmpty(): 0x1C and 0x1D....................................................................................................................... 24
2.15 MaxLoadCurrent(): 0x1E and 0x1F................................................................................................................................24
2.16 MaxLoadTimeToEmpty(): 0x20 and 0x21.......................................................................................................................24
2.17 RawCoulombCount(): 0x22 and 0x23............................................................................................................................ 24
2.18 AveragePower(): 0x24 and 0x25....................................................................................................................................24
2.19 InternalTemperature(): 0x28 and 0x29........................................................................................................................... 24
2.20 CycleCount(): 0x2A and 0x2B........................................................................................................................................24
2.21 StateOfCharge(): 0x2C and 0x2D.................................................................................................................................. 25
2.22 StateOfHealth(): 0x2E and 0x2F.................................................................................................................................... 25
2.23 ChargingVoltage(): 0x30 and 0x31.................................................................................................................................25
2.24 ChargingCurrent(): 0x32 and 0x33.................................................................................................................................25
2.25 BTPDischargeSet(): 0x34 and 0x35...............................................................................................................................25
2.26 BTPChargeSet(): 0x36 and 0x37................................................................................................................................... 25
2.27 OperationStatus(): 0x3A and 0x3B................................................................................................................................ 25
2.28 DesignCapacity(): 0x3C and 0x3D.................................................................................................................................26
2.29 MACData(): 0x40 through 0x5F..................................................................................................................................... 26
2.30 MACDataSum(): 0x60.................................................................................................................................................... 26
2.31 MACDataLen(): 0x61..................................................................................................................................................... 26
2.32 AnalogCount(): 0x79...................................................................................................................................................... 26
2.33 RawCurrent(): 0x7A and 0x7B....................................................................................................................................... 26
2.34 RawVoltage(): 0x7C and 0x7D.......................................................................................................................................26
3 Data Memory Interface......................................................................................................................................................... 27
3.1 Accessing the Data Memory............................................................................................................................................ 27
3.2 Device Access Modes......................................................................................................................................................27
3.3 Sealing and Unsealing Data Memory Access.................................................................................................................. 27
3.4 Data Memory Summary................................................................................................................................................... 28
4 Functional Description.........................................................................................................................................................45
4.1 Device Configuration........................................................................................................................................................45
4.1.1 CEDV Smoothing Config Register.............................................................................................................................45
4.1.2 Operation Configuration A (Operation Config A) Register.........................................................................................45
4.1.3 Operation Configuration B (Operation Config B) Register.........................................................................................46
4.2 External Pin Functions..................................................................................................................................................... 46
4.2.1 Pin Function Code (PFC) Descriptions......................................................................................................................46
4.2.2 Battery Presence Detection Using the BIN/TOUT Pin...............................................................................................47
4.2.3 SOC_INT Pin Behavior..............................................................................................................................................47
4.2.4 Power Path Control With the BAT_GD Pin................................................................................................................48
4.2.5 Battery Trip Point (BTP) Interrupts............................................................................................................................ 48
4.2.6 Wake-Up Comparator................................................................................................................................................49
4.2.7 Autocalibration...........................................................................................................................................................49
4.3 Temperature Measurement.............................................................................................................................................. 49
4.3.1 Overtemperature Indication....................................................................................................................................... 50
4.4 Charging and Charge Termination Indication...................................................................................................................50
4.4.1 Detecting Charge Termination................................................................................................................................... 50
4.4.2 Charge Inhibit............................................................................................................................................................ 50
4.5 Power Modes................................................................................................................................................................... 50
4.5.1 NORMAL Mode......................................................................................................................................................... 51
4.5.2 SLEEP Mode............................................................................................................................................................. 51
4.6 CONFIG UPDATE Mode..................................................................................................................................................52
4.7 BAT INSERT CHECK Mode.............................................................................................................................................52
4.8 Application-Specific Information.......................................................................................................................................52
4.8.1 Battery Profile Storage and Selection........................................................................................................................52
4.8.2 First OCV Measurement............................................................................................................................................53
4.9 Additional Data Memory Parameter Descriptions............................................................................................................ 53
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4.9.1 Calibration................................................................................................................................................................. 53
4.9.2 Coulomb Counter Offset............................................................................................................................................53
4.9.3 Board Offset...............................................................................................................................................................53
4.9.4 Int Temp Offset.......................................................................................................................................................... 53
4.9.5 Ext Temp Offset......................................................................................................................................................... 53
4.9.6 Pack VOffset..............................................................................................................................................................53
4.9.7 Internal Temp Model.................................................................................................................................................. 53
4.9.8 Ext a Coef and Ext b Coef......................................................................................................................................... 54
4.9.9 Filter...........................................................................................................................................................................54
4.9.10 Deadband................................................................................................................................................................ 54
4.9.11 CC Deadband.......................................................................................................................................................... 54
4.9.12 SOC Flag Configuration A (SOC Flag Config A) Register.......................................................................................54
4.9.13 SOC Flag Configuration B (SOC Flag Config B) Register.......................................................................................55
4.9.14 CEDV Gauging Configuration (CEDV Config) Register.......................................................................................... 56
4.9.15 EMF......................................................................................................................................................................... 57
4.9.16 C0............................................................................................................................................................................ 57
4.9.17 R0............................................................................................................................................................................ 57
4.9.18 T0............................................................................................................................................................................ 57
4.9.19 R1............................................................................................................................................................................ 57
4.9.20 TC............................................................................................................................................................................57
4.9.21 C1............................................................................................................................................................................ 57
4.9.22 Age Factor............................................................................................................................................................... 57
4.9.23 Fixed EDV0............................................................................................................................................................. 57
4.9.24 Fixed EDV1............................................................................................................................................................. 57
4.9.25 Fixed EDV2............................................................................................................................................................. 57
4.9.26 Battery Low %......................................................................................................................................................... 57
4.9.27 Low Temp Learning................................................................................................................................................. 58
4.9.28 Overload Current..................................................................................................................................................... 58
4.9.29 Self Discharge Rate.................................................................................................................................................58
4.9.30 Electronic Load........................................................................................................................................................58
4.9.31 Near Full.................................................................................................................................................................. 58
4.9.32 Reserve Capacity.................................................................................................................................................... 58
4.9.33 Charge Efficiency.....................................................................................................................................................58
4.9.34 Discharge Efficiency................................................................................................................................................ 58
4.9.35 Qmax Cell 1 and Qmax Pack.................................................................................................................................. 58
4.9.36 Learned Full Charge Capacity.................................................................................................................................58
4.9.37 DOD at EDV2.......................................................................................................................................................... 58
4.9.38 Cycle Count............................................................................................................................................................. 58
4.9.39 Design Capacity...................................................................................................................................................... 59
4.9.40 Design Voltage........................................................................................................................................................ 59
4.9.41 Cycle Count %.........................................................................................................................................................59
4.9.42 Charge Inhibit Temp Low.........................................................................................................................................59
4.9.43 Charge Inhibit Temp High........................................................................................................................................ 59
4.9.44 Temp Hys.................................................................................................................................................................59
4.9.45 Fast Charge Current................................................................................................................................................59
4.9.46 Charging Voltage..................................................................................................................................................... 59
4.9.47 Taper Current...........................................................................................................................................................59
4.9.48 Taper Voltage...........................................................................................................................................................60
4.9.49 SOC Delta............................................................................................................................................................... 60
4.9.50 Clock Control Register.............................................................................................................................................60
4.9.51 Sleep Current.......................................................................................................................................................... 60
4.9.52 Offset Calibration Inhibit Temperature Low..............................................................................................................60
4.9.53 Offset Calibration Inhibit Temperature High.............................................................................................................60
4.9.54 Sleep Voltage Time..................................................................................................................................................60
4.9.55 Sleep Current Time..................................................................................................................................................60
4.9.56 Dsg Current Threshold............................................................................................................................................ 60
4.9.57 Chg Current Threshold............................................................................................................................................ 60
4.9.58 Quit Current............................................................................................................................................................. 61
4.9.59 Dsg Relax Time....................................................................................................................................................... 61
4.9.60 Chg Relax Time....................................................................................................................................................... 61
4.9.61 Quit Relax Time....................................................................................................................................................... 61
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4.9.62 OT Charge...............................................................................................................................................................61
4.9.63 OT Chg Recovery....................................................................................................................................................61
4.9.64 OT Discharge.......................................................................................................................................................... 61
4.9.65 OT Dsg Recovery.................................................................................................................................................... 61
4.9.66 Initial Standby Current............................................................................................................................................. 61
4.9.67 Default Temperature................................................................................................................................................ 62
4.9.68 Device Name........................................................................................................................................................... 62
4.9.69 System Down Set Voltage....................................................................................................................................... 62
4.9.70 System Down Set Voltage Time.............................................................................................................................. 62
4.9.71 System Down Clear Voltage....................................................................................................................................62
4.9.72 Full Reset Counter...................................................................................................................................................62
4.9.73 Reset Counter Watchdog........................................................................................................................................ 62
5 Communications...................................................................................................................................................................63
5.1 I2C Interface..................................................................................................................................................................... 63
5.2 I2C Time Out.....................................................................................................................................................................63
5.3 I2C Command Waiting Time.............................................................................................................................................63
5.4 I2C Clock Stretching.........................................................................................................................................................64
6 Application Examples.......................................................................................................................................................... 65
6.1 Data Memory Parameter Update Example...................................................................................................................... 65
7 Open-Circuit Voltage Measurement Background.............................................................................................................. 67
7.1 Background...................................................................................................................................................................... 67
7.1.1 OCV Qualification and Calculation............................................................................................................................ 67
7.1.2 OCV Calculation Assumption.................................................................................................................................... 67
7.1.3 OCV Timing............................................................................................................................................................... 67
7.2 OCV Timing and OCV_CMD Use Recommendations..................................................................................................... 69
7.2.1 ACTIVE Mode (Fuel Gauge Is Not in SLEEP Mode).................................................................................................69
7.2.2 SLEEP Mode............................................................................................................................................................. 69
7.2.3 Initial OCV – POR......................................................................................................................................................69
8 Updating BQ27220 Configuration Parameters...................................................................................................................71
8.1 Gauge Mode FlashStream (gm.fs) Files.......................................................................................................................... 71
8.1.1 Write Command.........................................................................................................................................................72
8.1.2 Read and Compare Command..................................................................................................................................72
8.1.3 Wait Command.......................................................................................................................................................... 73
8.1.4 CONFIG UPDATE Mode........................................................................................................................................... 73
8.2 OTP Mode FlashStream (ot.fs) Files................................................................................................................................73
8.2.1 Write Command.........................................................................................................................................................74
8.2.2 Read and Compare Command..................................................................................................................................75
8.2.3 Wait Command.......................................................................................................................................................... 75
8.2.4 CONFIG UPDATE Mode........................................................................................................................................... 75
8.3 Programming Instructions................................................................................................................................................ 76
8.3.1 Using gm.fs Files....................................................................................................................................................... 76
8.3.2 Using ot.fs Files......................................................................................................................................................... 76
8.4 General Setup and Software Installation to Program OTP.............................................................................................. 77
8.5 Launch BQStudio Software..............................................................................................................................................77
8.6 Load .GG File...................................................................................................................................................................79
8.7 Confirm or Update Data Memory Parameters..................................................................................................................80
8.8 Save .OTFS File...............................................................................................................................................................82
8.9 Launch SmartFlash Software...........................................................................................................................................83
8.10 Open Ot.fs File............................................................................................................................................................... 84
8.11 Program OTP................................................................................................................................................................. 85
8.12 Confirm Success............................................................................................................................................................ 86
A Battery Gauge Glossary...................................................................................................................................................... 87
A.1 Glossary...........................................................................................................................................................................88
B Revision History...................................................................................................................................................................89
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1.1 About This Manual
This manual discusses the modules and peripherals of the BQ27220 device, and how each is used to build a
complete battery pack fuel gauge solution. For further information, refer to the BQ27220 System-Side CEDV
Fuel Gauge Data Sheet (SLUSCB7).
1.2 Formatting conventions used in this document:
Information Type Formatting Convention Example
Commands Italics with parentheses and no breaking spaces RemainingCapacity() command
Data Memory Italics, bold, and breaking spaces Design Capacity data
Register bits and flags Brackets and italics [TDA] bit
Data Memory bits Brackets, italics, and bold [LED1] bit
Modes and states ALL CAPITALS UNSEALED mode
1.3 Related Documentation from Texas Instruments
To obtain a copy of any of the following TI documents, go to the TI Web site at www.ti.com.
1. BQ27220 System-Side CEDV Fuel Gauge Data Sheet (SLUSCB7)
2. Going to Production with the BQ275xx Application Report (SLUA449)
3. Host System Calibration Method Application Report (SLUA640)
1.4 Trademarks
MathCAD™ is a trademark of MathSoft, Inc.
All trademarks are the property of their respective owners.
Preface
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The BQ27220 fuel gauge, using compensated end-of-discharge voltage (CEDV) technology, accurately predicts
the battery capacity and other operational characteristics of a single series, Li-based rechargeable cell. It can
be interrogated by a system processor to provide cell information such as time-to-empty (TTE), state-of-charge
(SOC), and the SOC interrupt signal to the host.
Information is accessed through a series of commands, called Standard Commands. Further capabilities are
provided by the additional Extended Commands set, both sets of commands, indicated by the general format
Command(), read and write information contained within the device control and status registers, as well as its
data memory locations. Commands are sent from system to gauge using the I2C serial communications engine,
and can be executed during application development, system manufacture, or end-equipment operation.
Cell information is stored in the device in One-Time Programmable (OTP) memory. Many of these data memory
locations are accessible during application development. They cannot, in general, be accessed directly during
end-equipment operation. Access to these locations is achieved by either using the companion evaluation
software, through individual commands, or through a sequence of data-flash–access commands. To access a
desired data memory location, the correct data memory address must be known.
The fuel gauge measures charge and discharge activity by monitoring the voltage across a small-value series
sense resistor (5 mΩ to 20 mΩ, typical) located between the system VSS and the battery PACK– terminal. When
a cell is attached to the device, information is based on cell current, cell open-circuit voltage (OCV), and cell
voltage under loading conditions.
The external temperature sensing is optimized with the use of a high-accuracy negative temperature coefficient
(NTC) thermistor with R25 = 10.0 kΩ ±1%. B25/85 = 3435 kΩ ± 1% (such as Semitec NTC 103AT). Alternatively,
the fuel gauge can be configured to use its internal temperature sensor or receive temperature data from the
host processor. The fuel gauge uses temperature to monitor the battery-pack environment, which is used for gas
gauging and cell protection functionality.
To minimize power consumption, the fuel gauge has several power modes: INITIALIZATION, NORMAL, SLEEP,
and SHUTDOWN. The fuel gauge passes automatically between these modes, depending upon the occurrence
of specific events, though a system processor can initiate some of these modes directly.
1.1 Gas Gauging
The BQ27220 device features the Compensated End-of-Discharge Voltage (CEDV) gauging algorithm, capable
of gauging a maximum capacity of 32 Ah.
Figure 1-1 shows the operational overview of the BQ27220 fuel gauge.
Chapter 1
General Description
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Figure 1-1. BQ27220 Gas Gauging Operational Overview
1.1.1 CEDV Gas Gauging Operational Overview
The BQ27220 device accumulates the measured quantities of charge and discharge and estimates self-
discharge of the battery. The BQ27220 device compensates the charge current measurement for temperature
and state-of-charge of the battery. The BQ27220 device also adjusts the self-discharge estimation based on
temperature. The initial battery state-of-charge estimation on first insertion of the battery pack in the system may
display a factor of the true value; the system must go through a full charge and then a full discharge cycle before
the correct full-charge capacity (FCC) is estimated.
The main charge counter, RemainingCapacity() (RM), represents the available capacity or energy in the battery
at any given time. The BQ27220 device adjusts RM for charge, self-discharge, and other compensation factors.
The information in the RM register is accessible through the I2C interface. The FullChargeCapacity() (FCC)
register represents the initial or last measured full discharge of the battery. It is used as the battery full-charge
reference for relative capacity indication. The BQ27220 device updates FCC after the battery undergoes a
qualified discharge from nearly full to a low battery level. FCC is accessible through the I2C interface.
The Discharge Count register (DCR) is an internal register that tracks discharge of the battery. The BQ27220
device uses the DCR to update the FCC register if the battery undergoes a qualified discharge from nearly
full to a low battery level. In this way, the BQ27220 device learns the true discharge capacity of the battery
under-system use conditions.
1.1.2 Main Fuel Gauge Registers
Remaining
Capacity
(RM)
Remaining capacity in the battery
RM represents the remaining capacity in the battery. The BQ27220 device computes RM in
units of mAh.
RM counts up during charge to a maximum value of FCC and down during discharge and
self-discharge to a minimum of 0. In addition to charge and self-discharge compensation,
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the BQ27220 device calibrates RM at three low-battery-voltage thresholds, EDV2, EDV1, and
EDV0. This provides a voltage-based calibration to the RM counter.
Design
Capacity
(DC)
User-specified battery full capacity
DC is the user-specified battery full capacity. It is calculated from Design Capacity mAh and is
represented in units of mAh. It also represents the full-battery reference for the absolute display
mode.
Full Charge
Capacity
(FCC)
Last measured discharge capacity of the battery
FCC is the last measured discharge capacity of the battery. It is represented in units of mAh.
On initialization, the BQ27220 device sets FullChargeCapacity() to the data flash value stored
in Learned Full Charge Capacity (FCC). During subsequent discharges, the BQ27220 device
updates FullChargeCapacity() with the last measured discharge capacity of the battery. The
last measured discharge of the battery is based on the value in the DCR after a qualified
discharge occurs. Once updated, the BQ27220 device writes the new FullChargeCapacity()
value to data flash in mAh to Learned Full Charge Capacity. FullChargeCapacity() represents
the full battery reference for the relative display mode and relative state-of-charge calculations.
Discharge
Count
Register
(DCR)
The DCR counts up during discharge, independent of RM. The DCR counts discharge activity,
battery load estimation, and self-discharge increment. The BQ27220 device initializes the DCR
at the beginning of a discharge to FCC – RM when RM is within the programmed value in Near
Full. The DCR initial value of FCC – RM is reduced by FCC/128 if [SC] = 1 in CEDV Gauging
Configuration and is not reduced if [SC] = 0. The DCR stops counting when the battery voltage
reaches the EDV2 threshold on discharge.
1.1.3 Capacity Learning (FCC Update) and Qualified Discharge
The BQ27220 device updates FCC with an amount based on the value in the DCR if a qualified discharge
occurs. The new value for FCC equals the DCR value plus the programmable Near Full and low battery levels,
per the following equation:
FCC (new) = DCR (final) = DCR (initial) + Measured Discharge to EDV2 + (FCC × Battery_Low%)
Where Battery_Low % = (Battery Low % value in data flash) ÷ 100
A qualified discharge occurs if the battery discharges from RM ≥ FCC – Near Full to the EDV2 voltage threshold
with the following conditions:
• No valid charge activity occurs during the discharge period. A valid charge is defined as a charge of 10 mAh
into the battery.
• No more than 256 mAh of self-discharge or battery load estimation occurs during the discharge period.
• The temperature does not drop below the low temperature thresholds programmed in Low Temp during the
discharge period.
• The battery voltage reaches the EDV2 threshold during the discharge period and the voltage is greater than
or equal to the EDV2 threshold minus 256 mV when the BQ27220 device detected EDV2.
• Current remains ≥ 3C/32 when EDV2 is reached.
• No overload condition exists when EDV2 threshold is reached, or if RM has dropped to
Battery_Low % × FCC.
The BQ27220 device sets [VDQ] = 1 in OperationStatus() when a qualified discharge begins. The BQ27220
device sets [VDQ] = 0 if any disqualifying condition occurs. One complication may arise regarding the state of
[VDQ] if [CSYNC] is set in CEDV Gauging Configuration. When [CSYNC] is enabled, RemainingCapacity() is
written to equal FullChargeCapacity() on valid primary charge termination. This capacity synchronization is done
even if the condition RM ≥ FCC – Near Full is not satisfied at charge termination.
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FCC cannot be reduced by more than 256 mAh or increased by more than 512 mAh during any single update
cycle. If [FCC_LIMIT] is set in CEDV Gauging Configuration then FCC cannot learn above the Design
Capacity mAh. The BQ27220 device saves the new FCC value to the data flash within 4 s of being updated.
1.1.4 End-of-Discharge Thresholds and Capacity Correction
The BQ27220 device monitors the battery for three low-voltage thresholds: EDV0, EDV1, and EDV2.
If the [EDV_CMP] bit in CEDV Gauging Configuration is clear, fixed EDV thresholds may be programmed in
Fixed EDV0, Fixed EDV1, and Fixed EDV2 in mV.
If the [EDV_CMP] bit in CEDV Gauging Configuration is set, automatic EDV compensation is enabled and
the BQ27220 device computes the EDV0, EDV1, and EDV2 thresholds based on values stored in the selected
CEDV profile in data flash and the battery's current discharge rate and temperature. If the [FIXED_EDV0] bit in
CEDV Gauging Configuration is also set, then the EDV0 threshold will be set to the programmed Fixed EDV0,
and the EDV1 and EDV2 compensated thresholds will not go below the programmed Fixed EDV0.
The BQ27220 device disables EDV detection if Current exceeds the Overload Current threshold. The BQ27220
device resumes EDV threshold detection after Current drops below the Overload Current threshold. Any EDV
threshold detected is reset after charge is applied and [VDQ] is cleared after 10 mAh of charge.
The BQ27220 device uses the EDV thresholds to apply voltage-based corrections to the RM register (see Table
1-1).
Table 1-1. State-of-Charge Based on Low Battery
Voltage
THRESHOLD RELATIVE STATE OF CHARGE
EDV0 0%
EDV1 3%
EDV2 Battery Low %
The BQ27220 device performs EDV-based RM adjustments with Current ≥ C/32. No EDVs are set if Current <
C/32. The BQ27220 device adjusts RM as it detects each threshold. If the voltage threshold is reached before
the corresponding capacity on discharge, the BQ27220 device reduces RM to the appropriate amount as shown
in Table 1-1.
If an RM % level is reached on discharge before the voltage reaches the corresponding threshold, then RM is
held at that % level until the threshold is reached. RM is only held if [VDQ] = 1, indicating a valid learning cycle is
in progress. If Battery Low % is set to zero, EDV1 and EDV0 corrections are disabled.
1.1.5 EDV Discharge Rate and Temperature Compensation
If EDV compensation is enabled, the BQ27220 device calculates battery voltage to determine EDV0, EDV1, and
EDV2 thresholds as a function of battery capacity, temperature, and discharge load. The general equation for
EDV0, EDV1, and EDV2 calculation is as follows:
EDV0,1,2 = n (EMF × FBL – |ILOAD| × R0 × FTZ) (1)
• EMF is a no-load cell voltage higher than the highest cell EDV threshold computed. EMF is programmed in
mV in the CEDV profile EMF.
• ILOAD is the current discharge load magnitude.
• n = the number of series cells. In the BQ27220 case n = 1.
• 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) (2)
• C (either 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 CEDV profile C0. C1 is the desired residual battery
capacity remaining at EDV0 (RM = 0). The C1 factor is stored in the CEDV profile C1.
• T is the current temperature in °K.
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• R0•FTZ represents the resistance of a cell as a function of temperature and capacity.
FTZ = f (R1, T0, C + C1, TC) (3)
• R0 is the first order rate dependency factor stored in the CEDV profile R0.
• T is the current temperature; C is the battery capacity relating to EDV0, EDV1, and EDV2.
• R1 adjusts the variation of impedance with battery capacity. R1 is programmed in the CEDV profile R1.
• T0 adjusts the variation of impedance with battery temperature. T0 is programmed in the CEDV profile T0.
• TC adjusts the variation of impedance for cold temperatures (T < 23°C). TC is programmed in the CEDV
profile TC.
The graphs below show the calculated EDV0, EDV1, and EDV2 thresholds versus capacity using the typical
compensation values for different temperatures and loads for a Li-Ion 18650 cell. The compensation values vary
widely for different cell types and manufacturers and must be matched exactly to the unique characteristics for
optimal performance.
Figure 1-2. (a) EDV Calculations vs Capacity for Various Temperatures, (b) EDV Calculations vs Capacity
for Various Loads
1.1.6 EDV Age Factor
The EDV Age Factor allows the BQ27220 device to correct the EDV detection algorithm to compensate for
cell aging. This parameter scales cell impedances as the cycle count increases. This new factor is used to
accommodate for much higher impedances observed in larger capacity and/or aged cells. For most applications,
the default value of zero is sufficient. However, for some very specific applications, this new aging factor may be
required. In those cases, experimental data must be taken at the 0, 100, 200, and 300 cycle read points using
a typical discharge rate while at ambient temperature. Entering this data into a TI provided MathCAD™ program
will yield the appropriate EDV Age factor value. Contact TI Applications Support @ http://www-k.ext.ti.com/sc/
technical-support/email-tech-support.asp?AAP for more detailed information.
1.1.7 Self-Discharge
The BQ27220 device estimates the self-discharge of the battery to maintain an accurate measure of the battery
capacity during periods of inactivity. The BQ27220 device makes self-discharge adjustments to RM every 1/4
second when awake and periodically when in SLEEP mode. The period is determined by Sleep Time.
The nominal self-discharge rate, %PERDAY (% per day), is programmed in an 8-bit value Self-Discharge Rate
by the following relation:
Self-Discharge Rate = %PERDAY/0.0025
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1.1.8 Battery Electronic Load Compensation
The BQ27220 device can be configured to compensate for a constant load (as from battery electronics) present
in the battery pack at all times. The BQ27220 device applies the compensation continuously when the charge or
discharge is below the digital filter. The BQ27220 device applies the compensation in addition to self-discharge.
The compensation occurs at a rate determined by the value stored in Electronics Load. The compensation
range is 0 μA–765 μA in steps of approximately 3 µA.
The amount of internal battery electronics load estimate in μA, BEL, is stored as follows:
Electronics Load = BEL/3
1.1.9 CEDV Configuration
Various gas gauging features can be configured by the CEDV Gauging Configuration register.
Table 1-2. CEDV Gauging Configuration Register
Feature Description
FCC_LIMIT
The FCC_LIMIT bit selects whether FCC limit can go above Design Capacity mAh.
0 = FCC can learn above Design Capacity mAh.
1 = FCC is limited to Design Capacity mAh.
SC
The SC bit enables learning cycle optimization for a Smart Charger or independent charge.
0 = Learning cycle is optimized for Smart Charger.
1 = Learning cycle is optimized for independent charger.
EDV_CMP
The EDV_CMP bit determines whether the BQ27220 device implements automatic EDV compensation to calculate the
EDV0, EDV1, and EDV2 thresholds based on rate, temperature, and capacity. If the bit is cleared, the BQ27220 device
uses the fixed values programmed in data flash for EDV0, EDV1, and EDV2. If the bit is set, the BQ27220 device calculates
EDV0, EDV1, and EDV2.
0 = EDV compensation is disabled.
1 = EDV compensation is enabled.
FIXED_EDV0
The FIXED_EDV0 bit selects whether EDV0 is always fixed.
0 = EDV0 is determined based on the [EDV_CMP] bit.
1 = EDV0 will always use Fixed EDV0. EDV1 and EDV2 compensation will not go below Fixed EDV0.
CSYNC
The CSYNC bit selects whether RM is set to FCC at charge termination.
0 = RM is not changed when charge termination is reached.
1 = RM will be set to FCC when charge termination is reached.
1.1.10 Initial Battery Capacity at Device Reset
The BQ27220 device estimates the initial capacity of a battery pack at device reset, which is the case when
battery cells are first attached to the application circuit. The initial FullChargeCapacity() (FCC) is a direct copy
of the data flash parameter Learned Full Charge Capacity. The initial RM and RSOC are estimated using the
open-circuit voltage (OCV) characteristics of the programmed Li-Ion chemistry, DOD at EDV2, and Qmax Pack.
This gives a reasonably accurate RM and RSOC; however, battery capacity learning is required in order to find
the accurate FCC, RM, and RSOC. During battery capacity learning, Learned Full Charge Capacity, and DOD
at EDV2 will be learned and updated.
The data flash Learned Full Charge Capacity, DOD at EDV2, and Qmax Pack, as well as the CEDV profile
parameters are stored separately for each of the four selectable battery profiles. However, there is only a single
OCV lookup table. The OCV table should be selected based on a best fit for all cell profiles.
The data flash parameter Learned Full Charge Capacity should be initialized to the Design Capacity mAh.
DOD at EDV2 should be initialized to (1 – Battery_Low%) × 16384, where Battery_Low% = Battery Low % ÷
100.
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1.1.11 Fuel Gauge Operating Modes
Entry and exit of each mode is controlled by data flash parameters in the Current Thresholds subclass. The
[DSG] flag referenced below is from the MAC GaugingStatus() subcommand and is set in both RELAXATION
and DISCHARGE modes. The [DSG] flag in BatteryStatus() is slightly different—it sets only in DISCHARGE
mode and not in RELAXATION mode.
CHARGE mode is exited and RELAXATION mode is entered when Current() goes below Quit Current
for a period of Chg Relax Time. DISCHARGE mode is entered when Current() goes below
(–)Dsg Current Threshold. DISCHARGE mode is exited and RELAXATION mode is entered when Current()
goes above (–)Quit Current threshold for a period of Dsg Relax Time. CHARGE mode is entered when
Current() goes above Chg Current Threshold.
Quit Current
(–)Quit Current
Current
Time
Relaxation Mode Charge Mode Discharge ModeRelaxation Mode Charge Mode Discharge Mode Relaxation Mode
Chg Relax Time
Dsg Relax Time
1 10 1 1 10[DSG]
Figure 1-3. Fuel Gauge Operating Mode Example
1.1.12 Qmax
Qmax is used for initial capacity (RM and RSOC) estimates in conjunction with the cell voltages and
programmed chemistry information when the device resets. The Qmax Pack value should be taken from the cell
manufacturers' data sheet multiplied by the number of parallel cells. This is also used for the DesignCapacity()
function and the Design Capacity mAh data flash value.
1.1.13 CEDV Smoothing
The BQ27220 device has the ability to smooth the RemainingCapacity() during discharge in order to avoid a
drop in RelativeStateOfCharge() when the EDV thresholds are reached. This feature is enabled by setting the
Smoothing Config [SMEN] = 1 and configuring the Smoothing Start Voltage and Smoothing Delta Voltage.
The smoothing will activate only when all of the following conditions are true:
•Current() < 0
•Voltage() < Smoothing Start Voltage
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• EDV2 has been reached ([EDV2] = 1) OR (Voltage() – present EDV2 threshold) < Smoothing Delta Voltage.
• Maximum Voltage() during the previous one minute is less than the maximum Voltage() during the current
minute (that is, "drop rate" is greater than 0).
•RemainingCapacity() is greater than the capacity at the next EDV point.
While smoothing is active, the "drop rate" is used to estimate the time to the EDV point under the assumption
that the rate is constant (linear). This information is then used to estimate how much current would need to be
applied in order to have RemainingCapacity() reach the expected capacity at the EDV point. The actual Current()
is then scaled by the "smoothing current." This will either speed up or slow down the RemainingCapacity()
accumulation to reach the EDV threshold at the correct time.
Whenever the RemainingCapacity() accumulation is actively scaled, the OperationStatus()[SMTH] bit will be set.
Smoothing deactivates whenever an EDV threshold is reached until the rate to the next EDV threshold can be
calculated. However, smoothing past the EDV2 point only occurs if the Smoothing Config [SMEXT] is set to 1.
To improve smoothing at the end of discharge, the SME0 configuration bit provides additional flexibility. This
is particularly useful when FIXED_EDV0 is set and the calculated EDV2/EDV1 is lower than EDV0. In this
scenario, the SOC smooths to EDV2, then to EDV1, and then to EDV0, leading to SOC jumps. If the SME0 bit is
set, then the SOC smooths directly to EDV0, leading to a smooth transition to empty.
Table 1-3 shows the available smoothing configurations.
Table 1-3. Smoothing Configurations
SMEN SMEXT SME0 Description
0 0 0 No Smoothing
0 0 1 No Smoothing
0 1 0 No Smoothing
0 1 1 No Smoothing
1 0 0 Smoothing to EDV2
1 0 1 Smoothing to EDV0 if calculated EDV2/EDV1 is less than EDV0.
1 1 0 Smoothing to EDV2 ≥ EDV1 ≥ EDV0
1 1 1 Smoothing to EDV0 if calculated EDV2/EDV1 is less than EDV0.
The BQ27220 device can also add smoothing during charging. In situations when the FCC is not updated during
a discharge cycle or on a subsequent charge cycle, if the valid charge termination is reached, RSOC is synced
to 100% regardless of the true RSOC. To help in scenarios like these, the device enables the SMOOTHEOC_EN
bit (default is enabled).
When enabled, the RSOC value is gradually increased to 100% instead of a sudden jump if the following is true:
1. Battery is charging.
2. Cell Voltage > Taper Voltage
3. Charge Current is decreasing AND is below the EOC Smooth Current threshold for EOC Smooth Current
Time.
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2.1 Standard Commands
The BQ27220 fuel gauge uses a series of 2-byte standard commands to enable system reading and writing of
battery information. Each standard command has an associated command-code pair, as indicated in Table 2-1.
Because each command consists of two bytes of data, two consecutive I2C transmissions must be executed
both to initiate the command function and to read or write the corresponding two bytes of data. Additional options
for transferring data are described in Table 2-2, Control() commands. Read and write permissions depend on the
active access mode, SEALED or UNSEALED. For details, see Section 3.2, Device Access Modes. See Chapter
5, Communications, for I2C details.
Table 2-1. Standard Commands
NAME COMMAND CODE UNIT SEALED
ACCESS
Control()/CONTROL_STATUS() CNTL 0x00 and 0x01 NA RW
AtRate() AR 0x02 and 0x03 mA RW
AtRateTimeToEmpty() ARTTE 0x04 and 0x05 Minutes R
Temperature() TEMP 0x06 and 0x07 0.1°K RW
Voltage() VOLT 0x08 and 0x09 mV R
BatteryStatus() Flags() 0x0A and 0x0B NA R
Current() Current() 0x0C and 0x0D mAh R
RemainingCapacity() RM 0x10 and 0x11 mAh R
FullChargeCapacity() FCC 0x12 and 0x13 mAh R
AverageCurrent() AI 0x14 and 0x15 mA R
TimeToEmpty() TTE 0x16 and 0x17 Minutes R
TimeToFull() TTF 0x18 and 0x19 Minutes R
StandbyCurrent() SI 0x1A and 0x1B mA R
StandbyTimeToEmpty() STTE 0x1C and 0x1D Minutes R
MaxLoadCurrent() MLI 0x1E and 0x1F mA R
MaxLoadTimeToEmpty() MLTTE 0x20 and 0x21 min R
RawCoulombCount() 0x22 and 0x23 mAh R
AveragePower() AP 0x24 and 0x25 mW R
InternalTemperature() INTTEMP 0x28 and 0x29 0.1°K R
CycleCount() CC 0x2A and 0x2B num R
RelativeStateOfCharge() SOC 0x2C and 0x2D % R
StateOfHealth() SOH 0x2E and 0x2F %/num R
ChargeVoltage() CV 0x30 and 0x31 mV R
ChargeCurrent() CC 0x32 and 0x33 mA R
BTPDischargeSet() 0x34 and 0x35 mAh
BTPChargeSet() 0x36 and 0x37 mAh
OperationStatus() 0x3A and 0x3B NA R
DesignCapacity() Design Cap 0x3C and 0x3D mAh R
Chapter 2
Standard Data Commands
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Table 2-1. Standard Commands (continued)
NAME COMMAND CODE UNIT SEALED
ACCESS
MACData() 0x40 through 0x5F
MACDataSum() 0x60
MACDataLen() 0x61
AnalogCount() 0x79
RawCurrent() 0x7A and 0x7B
RawVoltage() 0x7C and 0x7D
RawIntTemp() 0x7E and 0x7F
2.2 Control()/CONTROL_STATUS(): 0x00 and 0x01
Issuing a Control() (Manufacturer Access Control or MAC) command requires a 2-byte subcommand. The
subcommand specifies the particular MAC function desired. The Control() command allows the system to
control specific features of the fuel gauge during normal operation and additional features when the device is
in different access modes, as described in Table 2-2. On this device, Control() commands may also be sent to
ManufacturerAccessControl(). Any subcommand that has a data response will be read back on MACData().
Reading the Control() registers will always report the CONTROL_STATUS() data field except after the
DEVICE_NUMBER() and FW_VERSION() subcommands. After these subcommands, CONTROL_STATUS() will
report the value 0xFFA5 one time before reverting to the normal data response. This is a flag to indicate that the
data response has been moved to MACData(). Writing a 0x0000 to Control() is no longer necessary to read the
CONTROL_STATUS(), although it is okay if it is done.
When executing commands that require data (such as data flash writes), the subcommand can be written
to either Control() or ManufacturerAccessControl() registers; however, it is recommended to write using the
ManufacturerAccessControl() registers as this allows performing the full command in a single I2C transaction.
Table 2-2. Control() MAC Subcommands
CNTL/MAC FUNCTION SUBCOMMAND
CODE
SEALED
ACCESS? DESCRIPTION
CONTROL_STATUS 0x0000 Yes Ignored by the gauge (in previous devices would enable
CONTROL_STATUS() read)
DEVICE_NUMBER 0x0001 Yes Reports the device type (for example: 0x0320)
FW_VERSION 0x0002 Yes Reports the firmware version block (device, version, build, and
so on)
BOARD_OFFSET 0x0009 Yes Invokes the board offset correction
CC_OFFSET 0x000A Yes Invokes the CC offset correction
CC_OFFSET_SAVE 0x000B Yes Saves the results of the offset calibration process
OCV_CMD 0x000C Yes Requests the fuel gauge to take an OCV measurement
BAT_INSERT 0x000D Yes Forces BatteryStatus()[BATTPRES] bit set when Operation
Config B [BIEnable] bit = 0
BAT_REMOVE 0x000E Yes Forces BatteryStatus()[BATTPRES] bit clear when Operation
Config B [BIEnable] bit = 0
SET_SNOOZE 0x0013 Yes Forces CONTROL_STATUS()[SNOOZE] bit to 1
CLEAR_SNOOZE 0x0014 Yes Forces CONTROL_STATUS()[SNOOZE] bit to 0
SET_PROFILE_1 0x0015 Yes Select CEDV Profile 1
SET_PROFILE_2 0x0016 Yes Select CEDV Profile 2
SET_PROFILE_3 0x0017 Yes Select CEDV Profile 3
SET_PROFILE_4 0x0018 Yes Select CEDV Profile 4
SET_PROFILE_5 0x0019 Yes Select CEDV Profile 5
SET_PROFILE_6 0x001A Yes Select CEDV Profile 6
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Table 2-2. Control() MAC Subcommands (continued)
CNTL/MAC FUNCTION SUBCOMMAND
CODE
SEALED
ACCESS? DESCRIPTION
CAL_TOGGLE 0x002D No Toggles OperationStatus()[CALMD]
SEALED 0x0030 No Places the fuel gauge in SEALED access mode
RESET 0x0041 No Resets device
EXIT_CAL 0x0080 No Instructs the fuel gauge to exit CALIBRATION mode
ENTER_CAL 0x0081 No Instructs the fuel gauge to enter CALIBRATION mode
ENTER_CFG_UPDATE 0x0090 Yes Enter CONFIG UPDATE mode
EXIT_CFG_UPDATE_REINIT 0x0091 Yes Exit CONFIG UPDATE mode and re-initialize
EXIT_CFG_UPDATE 0x0092 Yes Exit CONFIG UPDATE mode without re-initialize
RETURN_TO_ROM 0xF00 No Places the device in ROM mode
An example using the DEVICE_NUMBER() subcommand:
• Write the data bytes 0x01 0x00 to the device address 0xAA starting at command 0x00.
• Then read the response using an incremental read. To the device address 0xAB, starting at command 0x3E,
read four bytes. The result would be 0x01 0x00 0x20 0x03 with the first two bytes reflecting subcommand,
and the second two bytes representing the device type in little endian order.
2.2.1 CONTROL_STATUS: 0x0000
A read on this command returns the 16-bit CONTROL_STATUS() data. The status word includes the following
information:
Table 2-3. CONTROL_STATUS Bit Definitions
Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
High Byte RSVD RSVD RSVD RSVD RSVD RSVD RSVD RSVD
Low Byte RSVD RSVD CCA BCA SNOOZE BATT_ID2 BATT_ID1 BATT_ID0
High Byte
RSVD = Reserved
Low Byte
RSVD = Reserved
CCA = Status bit indicating the fuel gauge Coulomb Counter Calibration routine is active. The CCA routine takes place
approximately 1 minute after the initialization and periodically as gauging conditions change. Active when set.
(See Section 4.2.7, Autocalibration.)
BCA = Status bit indicating the fuel gauge board calibration routine is active. Active when set.
SNOOZE = Status bit indicating the SNOOZE mode is enabled. True when set.
BATT_ID2 = Battery Identification Setting2. Battery identification settings for different chemistries, used in conjunction with
BATT_ID1 and BATT_ID0 (to select up to four chemistry IDs).
BATT_ID1 = Battery Identification Setting1. Battery identification settings for different chemistries, used in conjunction with
BATT_ID2 and BATT_ID0 (to select up to four chemistry IDs).
BATT_ID0 = Battery Identification Setting0. Battery identification settings for different chemistries, used in conjunction with
BATT_ID2 and BATT_ID1 (to select up to four chemistry IDs).
2.2.2 DEVICE_NUMBER: 0x0001
This command instructs the fuel gauge to return the device type 0x0220 to MACData().
2.2.3 FW_VERSION: 0x0002
This command instructs the fuel gauge to return the firmware revision on MACData() in the following format:
ddDDvvVVbbBBTTzzZZRREE, where
ddDD: Device Number
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vvVV: Version
bbBB: Build number
ttTT: Firmware type.
2.2.4 HW_VERSION: 0x0003
This command instructs the fuel gauge to return the hardware version on subsequent read of MACData().
2.2.5 BOARD_OFFSET: 0x0009
This command instructs the fuel gauge to measure and store the board offset value.
2.2.6 CC_OFFSET: 0x000A
This command instructs the fuel gauge to measure the internal CC offset value.
2.2.7 CC_OFFSET_SAVE: 0x000B
This command instructs the fuel gauge to store the internal CC offset value.
2.2.8 OCV_CMD: 0x000C
Requests the fuel gauge to take an open-circuit voltage (OCV) reading. This command can only be issued
after the OPERATION_STATUS()[INITCOMP] bit is set, indicating the initialization has been completed. The
OCV measurement takes place at the beginning of the next repeated 1-s firmware synchronization clock. If
the Operation Config A [INT_OCV] bit is set, the SOC_INT pin pulses for approximately 512 ms if BATG_EN
is 0, or 380 ms if BATG_EN is 1. (See also Table 4-6.) See Chapter 7, Open-Circuit Voltage Measurement
Background, for more details on OCV measurements and recommended usage of this command.
Note
The BatteryStatus()[OCVFAIL] bit is set if the OCV_CMD() subcommand is received when the
BatteryStatus()[CHGINH] bit is set.
2.2.9 BAT_INSERT: 0x000D
This command instructs the fuel gauge to force the BatteryStatus() [BATTPRES] bit to be set and informs
the gauge of the presence of a battery when the insertion detection feature is disabled (Operation Config B
[BIEnable] bit = 0). Alternatively, battery presence detection can be enabled (Operation Config B [BIEnable]
bit = 1) to monitor the external thermistor network. (See Section 4.2.2, Battery Presence Detection Using the BIN
Pin.)
2.2.10 BAT_REMOVE: 0x000E
This command instructs the fuel gauge to force the BatteryStatus() [BATTPRES] bit to clear when the battery
insertion detection is disabled (Operation Config B [BIEnable] bit = 0). Alternatively, battery presence detection
can be enabled (Operation Config B [BIEnable] bit = 1) to monitor the external thermistor network. (See
Section 4.2.2, Battery Presence Detection Using the BIN Pin.)
2.2.11 SET_SNOOZE: 0x0013
This command instructs the fuel gauge to set the CONTROL_STATUS [SNOOZE] bit to 1. This enables the
SNOOZE power mode. The gauge enters the SNOOZE power mode after the transition conditions are met.
2.2.12 CLEAR_SNOOZE: 0x0014
This command instructs the fuel gauge to set the CONTROL_STATUS [SNOOZE] bit to 0. This disables the
SNOOZE power mode. The gauge exits from the SNOOZE power mode after the [SNOOZE] bit is cleared.
2.2.13 SET_PROFILE_1/2/3/4/5/6: 0x0015–0x001A
This command instructs the device to switch the CEDV profile to one of the six pre-programmed profiles in the
gauge.
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