BQ27220: Using SOC_INT / GPOUT signal on BQ27220

David-Alexandre PANETTO

Part Number: BQ27220
Other Parts Discussed in Thread: BQSTUDIO

Tool/software:

I am trying to trigger OCV_CMD on BQ27220 over I2C bus and I configured Operation Config B for INT_POL and INT_OCV / INT_FOCV to be enabled so that I can see the GPOUT signal toggling when OCV measures are being done.

However I tried on the BQ27220 EVM board and also on your own product using the BQ27220.

To summarize, I am not able to see GPOUT pulses when I issuing OCV_CMD (000C).

Is there something to do special to see the GPOUT signal toggling ??

1) Do you have some config or I2C flow in example I could test to replicate on my side ?

2) Once OCV_CMD is sent over I2C, I can see all the time the OCVCOMP and OCVGD bits are set in status register. Then how to read the OCV value that has been computed ?? It's not clear in the TRM how to readback the computed value ...

Please help

9 months ago

0 Adrian 9 months ago

TI__Mastermind 37761 points

Hello David,

We are currently looking into this. Please allow us some time to get back with you.

Regards,

Adrian

0 Jonny 9 months ago in reply to Adrian

TI__Mastermind 24931 points

Hello,

There is an I2C example in the BQ27220 Technical Reference Manual, please see the image below.

You can read the measured OCV value by sending the 0x000C command to the MAC address 0x3E.

Regards,

Robert.

0 David-Alexandre PANETTO 9 months ago in reply to Jonny

Prodigy 60 points

Thanks a lot !

Spec is quite confusing, I sent the 000C command to the bad register actually ... That's why I didnt get GPOUT toggling, I will try it on Monday on real HW and let you know if it worked.

However with BQ27220 EVM board in BQSTUDIO I tried the OCV_CMD button last day but I didnt get any effect on GPOUT signal !

I configured GPOUT to be enabled to give me INT_OCV + INT_FOCV by changing the Operating Config B register to 0x1013 value, is it the good thing to do or is there any other register to set ??

Regards

0 David-Alexandre PANETTO 9 months ago in reply to Jonny

Prodigy 60 points

Hi,

I just tested sending 0x000C command to 3E register over I2C but I am reading back 0x0400 value which has no sense.

For informatiion the Voltage() function (address 0x08 and 0x09) returns 3890mV and seems to work correctly compared to the instrument measurement.

Regards

David

0 Jonny 9 months ago in reply to David-Alexandre PANETTO

TI__Mastermind 24931 points

Hello,

Can you send me the command sequence that you are sending?

Regards,

Robert.

0 David-Alexandre PANETTO 9 months ago in reply to Jonny

Prodigy 60 points

Here is the sequence :

1) Writing 00 0C to 0x3E register as suggested by your support

2) Then reading back the 0x61 register to read the MAC LEN

3) Then reading the data in register 0x40 with length determined from previous MAC_LEN

Regards

0 Jonny 9 months ago in reply to David-Alexandre PANETTO

TI__Mastermind 24931 points

Hello,

The OCV_CMD 0x000C command just requests that the gauge takes a new OCV measurement, it does not give you an OCV value to read back.

Regards,

Robert.

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BQ27220: Using SOC_INT / GPOUT signal on BQ27220