This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

bq20z60 sleep and shutdown modes

Other Parts Discussed in Thread: BQ20Z65-R1, BQ20Z60-R1

Hi,

I am programming a bq20z60 and after several tests I have seen that for some reason I cannot enter SLEEP and SHUTDOWN modes. I have tried to follow the SLUU386 reference manual but still is not working to me. What may I try to solve it?

Also I have seen that with no load, the current reported is -10mA and I guess it should be 0. What is it wrong there?

Finally, for charge termination I can can make the battery switch of at taper current limit, but it turns on again after 2 Taper Window periods. 

Looking fordward to hearing from you.

Thank you very much. 

Bimi.

  • Hello Bimi,

    can you check to see that the PRES bit is clear in the operation status register of the gauge. Also make sure you do not have any of the PF Status bits set as this prevents the device from going into both modes. If any of the pf bits is set, make sure the condition that caused it to be set is removed and then clear the pf by writing two word command 0x2673 0x1712. Then refer to the TRM of the device for the conditions for sleep and shutdown modes and make sure those conditions are observed.

    For the no load, -10mA current condition, you will need to calibrate the board offset and CCoffset to have zero Amps when no load is connected.

    For your charge termination issue, are you observing the primary charge termination conditions as noted in the TRM of the device?

     

    thanks

    Onyx

     

  • Hi Onix,

    Yes I have the PRES bit to 1. However I cannot reset it. How could I make it? Is it just HW connection or does it have also SW configuration?

    I do not have any permanent fails so is ok there.

    Thank you very much.

    Bimi.

  • hello Bimi,

    Pulling the /Pres pin low to ground sets the pres bit. You will have to keep that pin floating so the pres bit is clear. That's the only way you will be allowed to enter sleep mode.

    thanks

    Onyx

  • Hi Onyx, 

     I am not sure if I have understand you at all. In the RM says that

    If the [NR] bit is set to 0, [PRES] must also be set to 0 for the bq20z60-R1/bq20z65-R1 to enter sleep.

    However, if the [PRES] flag is 0, the CHG and DSG FETs go off. I only can charge or discharge if [PRES] flag is 1.

    Also, if I the keep the pin floating as you say, then also [PRES] flag is 0. So it does not work.

    Thank you in advanced.

    BIMI



  • Hello Bimi

    Also,check to make sure the sleep bit in the operation cfg A register is set. If cleared the device will never enter sleep mode.

    To be able to enter sleep mode,  Pres bit has to be cleared. The pres bit does not have to be set to enable discharging. You can write 0006 to the fet control register (46) to turn the fets on if you do not have /pres pulled to ground.

    Once you have made sure that the pres is clear and the sleep bit is set. Ensure that  one of the other conditions as stated in the sleep mode section of the TRM met.

    thanks

    Onyx

  • Hello Onix,

    I have follow your suggestions but is not entering in sleep mode. Here is my configuration.

    [NR] bit = 0; [Sleep] bit = 1; [PRES] bit =0; 

    I have writen 0006 in register 46 to turn on the fets and start discharging. Sleep current set to 100mA. Discharging current is 63mA.

    I have also disconnect the communication but nothing.

    One more thing. Now when the battery finish charging or discharging, the fets turn off and I have to enter 0006 to register (46) if I want to use it.

    Thank you very much.

    Best regards.

    Bimi.

  • hello Bimi,

    I tested the EVM for the bq20z60 and was able to put the device into sleep mode both when the NR bit was cleared ( pres ) bit was cleared as well as when the NR bit was set ( thus Pres bit is also set).

    I tested in two scenarios.

    1. sleep current set to 25mA. I had no load attached. NR=0, pres =0, sleep=1, wake current register=01.

    For yours, I would rather you have wake current register set to 00 to disable this functionality. In my case, wake current register as 01 means wake=0, rsns1=o,rsns0=1. This puts my wake voltage across the srn and srp pins as 0.5A*2.5mohm=0.00125 V. With my sense resistor being 10 ohms, the wake current is 0.125 A.

    I sent sleep command (0x11), disconnected the communication cable from the computer to ensure the lines are held low, and 20 sec afterwards, the device goes into sleep mode.

    2. For scenario two, I set NR=1, pres=1, sleep=1,wake current register=01

    I set my sleep current to 100mA, applied a load of 25mA. Sent the sleep command (0x11), disconnected the commucation cable from the computer, waited for about 20 secs and then the device went  into sleep mode.

    You can test your set up using either way. I recommend the second option since you want the pres bit to be set all the time so the fets can turn on/off the way you want it to. However, set the wake current register to 00 in the power tab section of data flash.

    thanks

    Onyx

  • Hi Onyx,

    I have tried both ways and don't know why still is not entering in sleep mode. If you come to any idea of what could be the problem I'll be listening.

    Anyway I will continue looking into it, and if I find the problem I will share it.

    Thank you.

    BIMI.

  • Hi Bimi,

    Not having your board makes it difficult to debug as I am able to put my device on my EVM to sleep. Try extracting a senc file from your chip on your board, program it on an EVM if you have one and try putting the device on the EVM to sleep. If you do not have an EVM, you can send over your senc and I will try on mine.

    thanks
    Onyx

  • Hi Onyx,

    I do not have any EVM. How could I extract a senc file? I cannot find any clear information related to this. Even more, I do not understand really well what is this file for.    

    The chemistry I use is ICR18650-22F, SDI manufacturer, which I know is something related to this.

    Best regards.

    Borja.

  • Hi Onyx,

    I have seen that the battery is sending out some data through SMBus every minute even if is connected or not. 

    Do you know why this could happen? 

    I have tried to enter in Shutdown mode with this condition:

    • (ManufacturerAccess shutdown command received AND Current = 0) AND PackVoltage <

    Charger Present threshold.

    Current and PackVoltage conditions are fullfilled. I have also looked at the SMBus communication signals and checked that the ManufacturerAccess command is correct.

    So there seems to be something in the ManufacturerAccess criteria that is wrong or missing, or maybe the command is somehow overridden by the mysterious data sent from the battery.

    Looking fordward to hearing from you.

    Best regards.

    Borja.

  • Hi Onyx,

    I finally made the shutdown mode work. But the sleep mode is still not working ok.

    With NR=0 the battery goes to Sleep mode, but ignores the Bus Low Time delay. And it will not wake up again even if I try different wake-up criteria (including Wake function with Wake Current Reg = 11). The only way I can force it to wake up is by setting the NR bit back to 1.

    But there must be some way to wake up it wihout changing the NR bit. Or some configuration is wrong. PRES input could cause the problem? 

    Please let me know your opinion.

    Thank you very much.

    BIMI.

  • Hello Bimi,
    I have been OOO hence my delayed response on here.
    The senc file is an image of the entire firmware on your IC. i.e consists of the instruction flash as well as the data flash parameters. Sending command 0x0f00 will put your device in ROM mode, then you can actually read out a .senc file. Post that file as a zipped folder to me and I will try putting my device into sleep mode using your settings.

    thanks
    Onyx

  • Thanks Onyx. I will send you as soon as possible.

    I still have the problem that when the battery finish charging or discharging the CHG and DSG FETs turn off and II have to send 0x0006 in register 46 to turn on again.

    Even if I change the NR bit I cannot solve that problem. How could I solve that?

    Best regards.

    BIMI.

  • Hello Bimi,

    send over your senc file and I will see what you are doing wrong.

    thanks

    Onyx

  • Hi Onyx,

    I have sent the command 0x0f00 and the communication with the device has stopped. It says that the communication is failed. 

    Do not know what I have done wrong.

    Please let me know what to do.

    Thanks.

    Borja.

  • I think I have managed to get it. I have send you to your direct email as I am having problems to attach this kind of file extension.

    My biggest concern about the programmation is that whenever I discharge the batteries the DSG and CHG FETs turn off and I cannot charge them again unless I enter 0x0006 in register 46.

    Best regards.

    Borja.

  • Hi Onyx,

    Sorry for not answering in such a long time. I've been very busy this last month.

    I finally made the electronic work properly. 

    After calibrating the electronic, by sending 0x0021, I forced the IC to make the impedance track algorithm and DSG and CHG FET's turn off problem was solved. Since then I could make the learning cycles properly.

    I also tested the shutdown and sleep modes after, and both were working ok.

    Thank you very much for your help.

    Bimi.