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BQ34Z110: BQ34z110 jump change SOC value during low consumption

Tomas Samek
Intellectual 300 points
Part Number: BQ34Z110
Other Parts Discussed in Thread: BQSTUDIO

Hello,

we are using BQ34z110 for a few years. Now our costumers announced problem with BQ34Z110 in ours device. If they turned off device with full charge Pb battery, when they turn it on the SOC value is jumped down for many percentages. It does not correspond to real consumption.We need repair it at our customers.

At device is used Pb battery 2x7200 mAh (12V) in serial connection.

Ours device has any function states, at each state is different consumption.

States
Turn OFF state S0 - average current 0,6mA (LED is OFF)
The microcontroler in deep sleep mode is periodicly waken up every 2 s for reading data from BQ34Z110 (reading SOC, AI, VOLT, FLAGS) at the state S0 .

S2 average current 61,25 mA (LED flashes (ON 500 ms, 80 mA/OFF 1500 ms, 55 mA)
S3 average current 287 mA (LED is ON)
S4 average current 70,2 mA (LED flashes (ON 500 ms, 82,7 mA/OFF 500 ms, 57,7 mA)

At states S2, S3 and S4 is measuring consumption correct.

We have measured that at state S0 happening jump change of value SOC about 21 % at the one moment. One time we measured at state S0 that SOC value has been 93% for 23 hours 55 minuts and 53 secods after this time SOC value have been changed to 71% although consumption is still the same (0,6 mA). It was happened more times, but we was not able to determine the exact time, it happens any times during weekend (from friday afternoon to monday morning). What could be wrong?

BQ34z110 setting:

[Header]

bq EVSW Version = 0.9.90
DeviceName = bq34z110 v0.04
Time = 1/7/2015 9:48:07 PM


[Safety(Configuration)]
OT Chg = 55.0
OT Chg Time = 2
OT Chg Recovery = 50.0
OT Dsg = 60.0
OT Dsg Time = 2
OT Dsg Recovery = 55.0
[Charge Inhibit Cfg(Configuration)]
Chg Inhibit Temp Low = 0.0
Chg Inhibit Temp High = 45.0
Temp Hys = 5.0
[Charge(Configuration)]
Suspend Low Temp = -5.0
Suspend High Temp = 55.0
Chg Eff = 100
Chg Eff Temp Comp = 25
Chg Eff Drop Off % = 96
Chg Eff Reduction Rate = 10
Maintenance Current = 0
[Charge Termination(Configuration)]
Taper Current = 100
Min Taper Capacity = 25
Cell Taper Voltage = 100
Current Taper Window = 40
TCA Set % = 99
TCA Clear % = 95
FC Set % = 100
FC Clear % = 98
DODatEOC Delta T = 10.0
[Data(Configuration)]
Rem Cap Alarm = 100
Design Cell Voltage = 2000
Initial Standby = -10
Initial MaxLoad = -500
Manuf Date = 01-Jan-1980
Ser. Num. = 0001
Cycle Count = 00
CC Threshold = 900
Design Cell Capacity = 7350
Design Cell Energy = 14700
SOH Load I = -400
TDD SOH Percent = 90
Cell Charge Voltage T1-T2 = 2250
Cell Charge Voltage T2-T3 = 2450
Cell Charge Voltage T3-T4 = 2350
Charge Current T1-T2 = 10
Charge Current T2-T3 = 50
Charge Current T3-T4 = 30
JEITA T1 = 0
JEITA T2 = 10
JEITA T3 = 45
JEITA T4 = 55
ISD Current = 10
ISD I Filter = 127
Min ISD Time = 7
Design Energy Scale = 1
Device Name = bq34z110
Manufacturer Name = Texas Inst.
Device Chemistry = PbA
[Discharge(Configuration)]
SOC1 Set Threshold = 150
SOC1 Clear Threshold = 175
SOCF Set Threshold = 75
SOCF Clear Threshold = 100
Cell BL Set Volt Threshold = 1800
Cell BL Set Volt Time = 2
Cell BL Clear Volt Threshold = 1850
Cell BH Set Volt Threshold = 2450
Cell BH Volt Time = 2
Cell BH Clear Volt Threshold = 2400
[Manufacturer Data(Configuration)]
Pack Lot Code = 0000
PCB Lot Code = 0000
Firmware Version = 0000
Hardware Revision = 0000
Cell Revision = 0000
DF Config Version = 0000
[Integrity Data(Configuration)]
Static Chem DF Checksum = 7CD5
[Lifetime Data(Configuration)]
Lifetime Max Temp = 30.0
Lifetime Min Temp = 14.9
Lifetime Max Chg Current = 1425
Lifetime Max Dsg Current = -798
Lifetime Max Pack Voltage = 29964
Lifetime Min Pack Voltage = 6024
[Lifetime Temp Samples(Configuration)]
LT Flash Cnt = 138
[Registers(Configuration)]
Pack Configuration = 0960
Pack Configuration B = FF
Pack Configuration C = 30
LED_Comm Configuration = 00
Alert Configuration = 0000
Number of series cell = 12
[Lifetime Resolution(Configuration)]
LT Temp Res = 1.0
LT Cur Res = 100
LT V Res = 25
LT Update Time = 60
[LED Display(Configuration)]
LED Hold Time = 4
[Power(Configuration)]
Flash Update OK Cell Volt = 1000
Sleep Current = 10
FS Wait = 0

[Manufacturer Info(System Data)]
Block A 0 = 00
Block A 1 = 00
Block A 2 = 00
Block A 3 = 00
Block A 4 = 00
Block A 5 = 00
Block A 6 = 00
Block A 7 = 00
Block A 8 = 00
Block A 9 = 00
Block A 10 = 00
Block A 11 = 00
Block A 12 = 00
Block A 13 = 00
Block A 14 = 00
Block A 15 = 00
Block A 16 = 00
Block A 17 = 00
Block A 18 = 00
Block A 19 = 00
Block A 20 = 00
Block A 21 = 00
Block A 22 = 00
Block A 23 = 00
Block A 24 = 00
Block A 25 = 00
Block A 26 = 00
Block A 27 = 00
Block A 28 = 00
Block A 29 = 00
Block A 30 = 00
Block A 31 = 00

[IT Cfg(Gas Gauging)]
Load Select = 2
Load Mode = 1
Max Res Factor = 15
Min Res Factor = 3
Ra Filter = 500
Fast Qmax Start DOD % = 92
Fast Qmax End DOD % = 96
Fast Qmax Start Volt Delta = 100
Cell Terminate Voltage = 1800
Cell Term V Delta = 25
ResRelax Time = 200
User Rate-mA = 0
User Rate-Pwr = 0
Reserve Cap-mAh = 0
Reserve Energy = 0
Max Scale Back Grid = 4
Cell Max DeltaV = 100
Cell Min DeltaV = 0
Max Sim Rate = 2
Min Sim Rate = 20
Ra Max Delta = 44
Qmax Max Delta % = 5
Cell DeltaV Max Delta = 10
Fast Scale Start SOC = 10
Charge Hys V Shift = 40
[Current Thresholds(Gas Gauging)]
Dsg Current Threshold = 60
Chg Current Threshold = 75
Quit Current = 20
Dsg Relax Time = 60
Chg Relax Time = 60
Quit Relax Time = 1
Cell Max IR Correct = 400
[State(Gas Gauging)]
Qmax Cell 0 = 7344
Cycle Count = 0
Update Status = 02
Cell V at Chg Term = 2466
Avg I Last Run = -712
Avg P Last Run = -1413
Cell Delta Voltage = 1
T Rise = 20
T Time Constant = 1000

[OCVa Table(OCV Table)]
Chem ID = 0804

[R_a0(Ra Table)]
Cell0 R_a flag = 0000
Cell0 R_a 0 = 45
Cell0 R_a 1 = 39
Cell0 R_a 2 = 32
Cell0 R_a 3 = 29
Cell0 R_a 4 = 25
Cell0 R_a 5 = 23
Cell0 R_a 6 = 20
Cell0 R_a 7 = 21
Cell0 R_a 8 = 21
Cell0 R_a 9 = 22
Cell0 R_a 10 = 23
Cell0 R_a 11 = 23
Cell0 R_a 12 = 23
Cell0 R_a 13 = 23
Cell0 R_a 14 = 23
[R_a0x(Ra Table)]
xCell0 R_a flag = 0055
xCell0 R_a 0 = 45
xCell0 R_a 1 = 39
xCell0 R_a 2 = 32
xCell0 R_a 3 = 29
xCell0 R_a 4 = 25
xCell0 R_a 5 = 23
xCell0 R_a 6 = 20
xCell0 R_a 7 = 21
xCell0 R_a 8 = 21
xCell0 R_a 9 = 22
xCell0 R_a 10 = 23
xCell0 R_a 11 = 23
xCell0 R_a 12 = 23
xCell0 R_a 13 = 23
xCell0 R_a 14 = 23

[Data(Calibration)]
CC Gain = 10.357
CC Delta = 10.337
CC Offset = -0.67
Board Offset = -0.21
Int Temp Offset = 0.0
Ext Temp Offset = -.9
Voltage Divider = 37586
[Current(Calibration)]
Deadband = 5

[Codes(Security)]
...

Thanks you for your help.
Best regards

Tomas Samek

  • 0
    TI__Mastermind 25955 points

    Hi Tomas,

    In S0, is the gauge powered off while a host MCU is running with an average current draw of 0.6 mA? Is the gauge powered during this time?

    If the gauge is turned off, it will not be able to track the current flow.

    Was the gauge operating properly for years, prior to this event?

    If the gauge is not powered in mode S0, please power the device.  The device cannot operate while physically powered down.  It has its own sleep modes.  It can operate in sleep mode when the sleep current is set with respect to the the current draw of the system.


    Sincerely,
    Bryan Kahler

  • 0 in reply to Bryan Kahler
    Intellectual 300 points

    Hi Bryan, 

    "In S0, is the gauge powered off while a host MCU is running with an average current draw of 0.6 mA? Is the gauge powered during this time?"

    Gauge (BQ34z110) is powered from the same power supply as MCU (STM8S207). It is garanted by hardware design. Is not posible that one of them is powered and the other not. MCU and BQ34z110 has together average current 0,6 mA, we have measured them. Microcontroler (STM8S207) is in active deep sleep mode with current draw of about 400 uA. Gauge and MCU is powered if there are Pb batteries connected.

    "If the gauge is turned off, it will not be able to track the current flow."
    It is clear, when gauge is not supply powered can not measure. Device is powered the whole time, when anybody start to charge device, device is automaticly starts up to state S2. For this reason we are mesuring Pb battery during S0 state (for user it looks like turned off state) beacause we have to need to check if it is not connected charger.

    "Was the gauge operating properly for years, prior to this event?"
    Devices are used by different customers. Some of them use it every day and they do not any problem. One new customer which use device seldom told us that SOC value has been jumping down to much although they do not use the device.

    "If the gauge is not powered in mode S0, please power the device. The device cannot operate while physically powered down. It has its own sleep modes. It can operate in sleep mode when the sleep current is set with respect to the the current draw of the system."

    At state S0:
    Gauge's power supply is not never interrupted. I am expect Gauge in SLEEP mode, because SLEEP bit in the CONTROL STATUS flags is set to 1 (Gauge setting: Sleep Current = 10, Pack Configuration = 0960 - SLEEP bit is SET to 1, AI =0).

    Every 2 s MCU read from Gauge SOC, AI, VOLT and FLAGS register. For 47.8647 hours Gauge is measuring SOC = 93 % at AI=0 mA. After 47.8647 hours Gauge is measuring SOC = 71% at AI = 0 mA. SOC value is changing in one moment. How is it posible? What can be wrong?

    I 

    Thanks you for help, best regards

    Tomas Samek

  • 0 in reply to Tomas Samek
    TI__Mastermind 25955 points
    Hi Tomas,

    Update Status = 02. Is this a copy of the golden master settings used in production prior to IT being enabled? The cells are learned, but IT is not enabled. If this is a copy of the settings from the failed unit, please ensure IT is enabled.

    If the issue persists, please use bqStudio to capture a log of the event and send the log as well as the SREC from the device for analysis.

    Sincerely,
    Bryan Kahler
  • 0 in reply to Bryan Kahler
    Intellectual 300 points
    Hello Bryan,

    "Update Status = 02. Is this a copy of the golden master settings used in production before IT is enabled? IT is enabled. "

    During setting the gauge (BQ34z110) we send IT ENABLE command. I am sure that IT is enabled. Golden master setting is the same at all our devices.

    bqStudio:
    I2C Command: 00, Data Block: 4100, pressed „Write Data“ (RESET)
    I2C Command: 00, Data Block: 2100, pressed „Write Data“ (IT_ENABLE)
    I2C Command: 00, Data Block: 2000 , pressed „Write Data“ (SEALED)

    "If the problem persists, please use bqStudio to capture the log of the event and send the log as well as the SREC from the device for analysis."

    From monday's afternoon up to now I am making logs of the gauge with bqStudio. The fives times SOC value has been fallen down by jump.
    18.2.2019 14:33:00 SOC = 99% start logging

    20.2.2019 14:33:03 SOC = 97%
    20.2.2019 15:32:53 SOC = 91%
    20.2.2019 16:32:48 SOC = 89%
    20.2.2019 17:32:39 SOC = 88%
    20.2.2019 18:32:30 SOC = 87%

    22.2.2019 14:19:00 SOC = 87% now
    The whole time is device in state S0, the whole time is running current draw of 0.6 mA.

    I am going to continue up to the end of week. After this I will send you the logs from measure.

    Best regards

    Tomas Samek
  • 0 in reply to Tomas Samek
    TI__Mastermind 25955 points
    Hi Tomas,

    Thank you for making the logs, I look forward to reviewing them.

    Please also provide a SREC from the beginning of each log so I may simulate on this end with the state of the gauge prior to event.

    Sincerely,
    Bryan Kahler
  • 0 in reply to Bryan Kahler
    Intellectual 300 points

    Hello Bryan,

    I am sending logs from measure gauge. Logs are logged every 2 s at program bq Evaluation Software. Logging started 18. 2. 2019 13:21:16, last log is from 25.2.2019 8:47:42.  

    Update status is set to 0x06 (exported DAata flash file 2019-02-25 0929 gauge data flash.gg).

    "Please also provide a SREC from the beginning of each log so I may simulate on this end with the state of the gauge prior to event."

    I am not sure what mean SREC? Every log has sequence number and time stamp.

    Best regards

    Tomas Samek

    https://e2e.ti.com/cfs-file/__key/communityserver-discussions-components-files/196/0028.2019_2D00_02_2D00_18-1321.7zhttps://e2e.ti.com/cfs-file/__key/communityserver-discussions-components-files/196/2019_2D00_02_2D00_25-0929-gauge-data-flash.7z

  • 0 in reply to Tomas Samek
    TI__Mastermind 25955 points
    Hi Tomas,

    The SREC is the firmware and dataflash settings of the gauge. To export, go to 'data memory' tab in bqStudio, click on 'read all', then click on 'golden image' tab, ensure SREC output is selected and then export the SREC.

    Please export these prior to the test so the values are the same as what were in the gauge prior to performing the test. For example, average i last run, average p last run, qmax, dod0, etc... may change during the test. To simulate accurately their state should be known prior to each test.

    Also, where you say update status was set to 0x06, was this updated by the gauge, or manually set to 0x06?

    Sincerely,
    Bryan Kahler
  • 0 in reply to Bryan Kahler
    Intellectual 300 points

    Hello Bryan,

    "The SREC is the firmware and dataflash settings of the gauge. To export, go to 'data memory' tab in bqStudio, click on 'read all', then click on 'golden image' tab, ensure SREC output is selected and then export the SREC."

    In my version bqStudio (0.9.90) is not "data memory", only "Data flash". I can "read all" but there is not any "golden image' tab. I can do only export to .gg file. I will try it with the newest bqStudio.

    "Please export these prior to the test so the values are the same as what were in the gauge prior to performing the test. For example, average i last run, average p last run, qmax, dod0, etc... may change during the test. To simulate accurately their state should be known prior to each test."

    OK I will repeat the exam.

    Also, where you say update status was set to 0x06, was this updated by the gauge, or manually set to 0x06?

    We import golden file through bqStudio (update status is set to 0x02).
    Update status is not updated manualy, but is changed by IT_ENABLE command (I2C Command: 00, Data Block: 2100, pressed „Write Data“).

    Best regards,

    Tomas Samek

  • 0 in reply to Tomas Samek
    Intellectual 300 points
    Hello Bryan,

    at your web side for BQ34Z110 is still link to SLUC407 (bq Evaluation Software version 0.9.90)
    www.ti.com/.../BQ34Z110

    Battery Management Studio (bqStudio) 1.3.54.1 is not supported by bq34z110.

    I can only export setting from Data Flash with bq Evaluation Software version 0.9.90. I do not know how I can do export SREC?

    Best regards,

    Tomas Samek
  • 0 in reply to Tomas Samek
    TI__Mastermind 25955 points
    Hi Tomas,

    My apologies, please use the EVSW tool to export a SENC file.

    Sincerely,
    Bryan Kahler
  • 0 in reply to Bryan Kahler
    Intellectual 300 points

    Hello Bryan,

    at bq Gas Gauge Evaluation Software on the I2C Pro cart is there a button "Read to * .senc file". When I use this button it show me error message "Comm error code = 772". Is there any command which enable read sence file? Why I can not read sence file from Bq34Z110?


    I2C communication is functioned because I was able to read data through "READ_Data" button.

    Best regards,

    Tomas Samek

  • 0 in reply to Tomas Samek
    TI__Mastermind 42535 points
    You need to be in full access mode to export the senc.
  • 0 in reply to Batt
    Intellectual 300 points
    Hello Bryan and Batt,

    for reading sence file is necessary send to I2C 000F to place device into ROM mode. When I read sence file I have to push "execute" button otherwise I can not read DATA RAM.

    I have started new test from yesterday. If the value state of charge will be changed with jumped I will send you logs and senc files.

    Best regards,

    Tomas Samek
  • 0 in reply to Tomas Samek
    TI__Mastermind 25955 points
    Hi Tomas,

    Thank you for the update. Hopefully the issue is resolved. If not, I look forward to reviewing the logs with you.

    Sincerely,
    Bryan Kahler
  • 0 in reply to Bryan Kahler
    Intellectual 300 points

    Hello Bryan,

    after 24 hours in the state S0 ( device has the average current 0,7 mA) was the value "State Of Charge" (SOC) changed by jump from 99% to 92%, after next hour SOC value changed from 92% to 88%. I send logs and two senc files to you from measuring. Before I started measuring I have readed file "2019-03-05 1046 START STATE.senc" from the gauge. At the end of measuring I read file "2019-03-07 1345 STOP STATE.senc" from the gauge. I hope that measured data will be usefull for finding out why SOC is changing by jump after 24 hours at low consumption.

    Thanks for help, best regards,

    Tomas Samek

    https://e2e.ti.com/cfs-file/__key/communityserver-discussions-components-files/196/2678.2019_2D00_02_2D00_25-0929-gauge-data-flash.7z

  • 0 in reply to Tomas Samek
    TI__Mastermind 25955 points
    Hi Tomas,

    Thank you for sending the files. Due to current loading, will be able to provide an update by EOD Tuesday.

    Sincerely,
    Bryan Kahler
  • 0 in reply to Bryan Kahler
    Intellectual 300 points

    Hello Bryan, 

    when I can expect some result from checking files that I have sent?  You wrote Tuesday. Today is Friday and i do not have any answer. 

    Best regards,

    Tomas Samek

  • 0 in reply to Tomas Samek
    TI__Mastermind 42535 points
    I'm helping Bryan out temporarily here. I don't see your files attached. Have you moved this to PM with him?
  • 0 in reply to Batt
    Intellectual 300 points

    Hello Batt,


    I do not know about moving files. I can see attachment in message from Mar 7, 2019 1:33 PM.

    I resend logs and *.sence files again.

    Best regards,

    Tomas Samek

    https://e2e.ti.com/cfs-file/__key/communityserver-discussions-components-files/196/2019_2D00_03_2D00_05-BQ34Z1110.7z

  • 0 in reply to Bryan Kahler
    Intellectual 300 points

    Hello Bryan, 

    all SENC files are in the folder "2019-03-05 BQ34Z1110.7z". The folder is attachment of this message. I can not add SENC file directly to chat, SENC file is not supported as attachment. I don't understand why you want to send SENC file, when I have already sent.

    Before I started test (read logs) I have readed "2019-03-05 1046 START STATE.senc".

    When I stoped logging I have readed "2019-03-07 1345 STOP STATE.senc".

    Best regards, 

    Tomas Samek

    https://e2e.ti.com/cfs-file/__key/communityserver-discussions-components-files/196/0844.2019_2D00_03_2D00_05-BQ34Z1110.7z

  • 0 in reply to Bryan Kahler
    Intellectual 300 points

    https://e2e.ti.com/cfs-file/__key/communityserver-discussions-components-files/196/1425.2019_2D00_03_2D00_05-BQ34Z1110.7zHello Bryan,

    all SENC files are in the folder "2019-03-05 BQ34Z1110.7z". The folder is attachment of this message. I can not add SENC file directly to chat, SENC file is not supported as attachment. I don't understand why you want to send SENC file, when I have already sent.

    Before I started test (read logs) I have readed "2019-03-05 1046 START STATE.senc".

    When I stoped logging I have readed "2019-03-07 1345 STOP STATE.senc".

    Best regards,

    Tomas Samek

  • 0 in reply to Tomas Samek
    TI__Mastermind 25955 points
    Hi Tomas,

    Thank you for the files. Will have an update by EOD Friday.

    Sincerely,
    Bryan Kahler
  • 0 in reply to Bryan Kahler
    TI__Mastermind 25955 points
    Hi Tomas,

    I am reviewing this internally with the algorithms team. Will provide another update on Tuesday.

    Sincerely,
    Bryan Kahler
  • 0 in reply to Bryan Kahler
    Intellectual 300 points

    Hello Bryan, 

    Do you have any update? Have you reviewed it with algorithms team?

    Our customer is realy nervous, that we do not have any answers. 

    Best regard, 

    Tomas Samek

  • 0 in reply to Tomas Samek
    Intellectual 300 points
    Hello Bryan,

    I have not received any answer. This issue is not resolved.

    Sincerely,

    Tomas Samek
  • 0 in reply to Tomas Samek
    TI__Mastermind 25955 points
    Hi Tomas,

    After review of the gg.csv file, cc threshold appears to be low.

    With a minimum lifetime voltage of 6V, please try reducing the value of flash update OK cell volt to 0 and rerunning the test. Are the results replicated? Please adjust to the default value of load mode 0 and load select 1. Is the SOC jump still seen?

    If the issues persist, please let us know.

    Sincerely,
    Bryan Kahler
  • 0 in reply to Bryan Kahler
    Intellectual 300 points
    Hello Bryan,

    I have changed value "flash update OK cell volt" to 0 in the "data flash".
    I have changed value Load Select from 2 to 1 and Load mode from 1 to 0.
    After 48 hours long test I will tell you if SOC value jumped.

    Best regard,

    Tomas Samek
  • 0 in reply to Tomas Samek
    TI__Mastermind 25955 points
    Hi Tomas,

    Thank you for the update!

    Sincerely,
    Bryan Kahler
  • 0 in reply to Bryan Kahler
    Intellectual 300 points

    https://e2e.ti.com/cfs-file/__key/communityserver-discussions-components-files/196/2019_2D00_04_2D00_10-BQ34Z110.7z

    Hello Bryan,

    I have done measuring, when I have change "flash update OK cell volt" to 0 and changed value Load Select from 2 to 1 and Load mode from 1 to 0, SOC value did not jump after 48 hours. The measured value are as attachement of this message.

    Senc file at the begin of measuring "2019-04-10 1500 START STATE.senc".
    Senc file at the end of measuring "2019-04-15 1050 STOP STATE.senc".
    Logs during measure "2019-04-15 1050 STOP STATE.log".

    What should I change in my golden files for bq34z110? When I change value Load Select, Load mode and flash update OK cell volt should I create new golden file with new setting?

    Thank for your help, best regards

    Tomas Samek

  • 0 in reply to Tomas Samek
    TI__Mastermind 25955 points
    Hi Tomas,

    Assuming the pack is already learned and calibrated, just changing these settings should not have an impact. Please follow the production steps for goldenizing the image such as setting the learned/update status to 0x02, setting cycle count to 1 and resetting lifetime values. If you previously used averaged calibration values across several boards with low variance, those values may be modified in the gg file as well.

    Sincerely,
    Bryan Kahler