bq78PL114S8 extended / block SBData commands

Look in the new version of SLUU330, revision B.  Page 66 shows SBS Command for reading Cell Temperatures 1 to 4.  Release of a protocol document to read/write parameters, like the bqWizard does, has not been scheduled.

What speciially are you interested in reading/writing that you cannot do right now?  Perhaps there is a work-around?

Hi,

I use the bq78pl114 EVM-001 (Firmware 4452).

Is there already a solution to get e.g. the single voltage of each cell ?

Is there another table or list of commands for the chip, so that i can read out the values direct from the chip via SMBus ?

The table in the SLUU330A don't cover all parameters that are available from the chip. The bqwizzard is able to get all single voltage of  all 8 cells or the temperature of each sensor, but the table only shows the commands for max. temperature of all cells or only the single voltage of cell 1 to 4.

Where can i find the definition for measured  binar data? Something like a look-up table where i can see which binar code describe e.g. which the voltage value were measured or temperature or ... .

David S said:

...  I am monitoring the SMBus communications between bqWizard and the bq78PL114, and I can see that the wizard is using block write and block read commands to communicate with the chip.  Can anyone provide me with the formats for the SBD block commands for the chip?  Also, can anyone point me to some documentation on SBData command mapping for the bq78PL114, or explain how to interpret the the information provided in the SBData Command Mapping utility within the bqWizard?

This would be also nice to know.

Thanks

Check update to SLUU330A, called SLUU330B.  This has the 12 cell voltages and first four cell temperatures available through SMBus on page 66.

Hi Jim,

for our application we need access to the following parameters:

Cell Temperature for cell 5 to 8 (via bq76pl102)

Number of pumps for each cell, because this is a very good measurement for the state of health of the single cells

We have no problems signing an NDA if this would help you.

Thanks Dirk

Dirk,

In a recent post, Jim states that the NDA will be lifted soon, but does not specify a target date. See this thread from 08-09-2010 "Using bq78PL114+bq76PL102 on 20 cells LifePo4 battery pack".

David

Hi David,

since we need a quick solution I would prefer signing an NDA instead of waiting. Should I send you our standard NDA or do you have one for this purpose? Please contact me directly via email.

Thanks Dirk

Dirk,

I have no association with TI other than the fact I am trying to get the same information.  I too would gladly sign an NDA, but TI does not seem to want to go that route.  BTW, you have to edit your profile to allow anyone to contact you directly by email.  profile>settings>site options>allow conversations from all users.

David

How can we measure temperatures beyond 4 cells ? Because bqwizard , firmware 6000 loaded on bq78pl116  does not allow more than 4 temperature sensors to be associated (which means it is not possible to access bq76pl102 's temperature information ?) with any cells.

I appreciate  your precious suggestions.

That's the way I understand the documentation.  Evidently TI does not think additional temperature sensors are worth the required register allocation.  If additional temperature measurements are critical in your application, there are some stand-alone temperature sensors with SMB / I2C interface such as Maxim MAX6581 and Burr Brown / TI TMP100 or TMP101 that can be used to acquire additional system level temperature measurements.

David

We currently do not provide access to the Temp information from the temp sensor on board the PL102.

These parts are normally located on the PCB and do not normally measure the cell temperature.

The use of 4 strategically placed temp sensors in the cell pack allows the user to optimized the performance parameters for their application.

Regards,

Ben

Dear Ben , thank you for the reply.

Is there any way to fix "0 cells found" problem? I could not found any answers to that issue on the forum.

Sercan

Dear Sercan,

one reason could be that one of your cells has no connection to the chip or a very strange voltage. In any case try to relearn / initialize. Make sure that no other device is communicating with the TI chip, this is very critical!

Best regards,

Dirk

Hi Sercan,

The last time I had an issue as you described, I had to have the PL114 IC replaced. I think in your case, you will have to acquire a new daughter card.

Also try the standrd trics of ensuring you gave SMBus Comms to the part, that the VSS and V1, V2, V3 are connected. Try following the proposed connection sequence out lined in : http://focus.ti.com/lit/ug/sluu474/sluu474.pdf page 18.

Regards,

Ben

Additionally,

 You will need to ensure that the PowerLAN Network between bq78PL116 & bq76PL102

 “Zero cells found” could also mean,

Lest some basics are not overlooked, one must follow the USB-TO-GPIO adapter setup as specified in section 1.4.1 of SLUU336C, and follow the start-up procedure of section 1.5, or the "zero cells found" error message will occur.

David