BQ40Z80EVM-020: Error with connecting BQ40Z80EVM-020 to Battery Management Studio by TI

Bhavil Nagar

Part Number: BQ40Z80EVM-020
Other Parts Discussed in Thread: BQ40Z80, BQSTUDIO, EV2400

I recently got my hands on the BQ40Z80EVM-020 module and followed the procedure to download the Battery Management Studio which would help me to develop the board. I want to use the board to develop a BMS. I am now facing a lot of issues connecting the board with the Studio. After the startup, the board loses connection and I receive the error "No acknowledge from device". I have tried everything which was suggested in the FAQs but am still facing the same issue. I feel that the board is going into Auto Shutdown mode, as every time I open the Battery Management Studio, I have to wake the board up. The values of the voltages of the batteries also come up as blank or 0.

Any help on this matter would be appreciated.

over 2 years ago

0 Shirish over 2 years ago

TI__Guru 57697 points

Hello Bhavil,

Check that all cell connections are correct and that there is sufficient voltage at each cell input to the EVM. Is the voltage reading of the lowest cell also showing 0?

A blank value is shown when there is a Nack.

0 Bhavil Nagar over 2 years ago in reply to Shirish

Intellectual 365 points

Hi Shirish,

I checked the connections and they seem good to me and measured the voltage at the input, which also is coming out fine. The app shows the Cell 1 Voltage is 0mv whereas if I check the potential between 1N and 1P it comes out to be somewhere around 3V.

After connecting to the app initially, if I hit refresh, the app fluctuates between 2 error messages "No Acknowledge from device" and "Timeout or unexpected response communicating with the device"

0 Wyatt Keller over 2 years ago in reply to Bhavil Nagar

TI__Guru** 105770 points

Hello Bhavil,

Can you share a screenshot of the errors and the voltage readings from your tests?

Sometimes you need to hold the wakeup button until the cell config is set to the proper number of cells or it will keep going to shutdown based on voltage. How many cells in series are you trying to test?

Sincerely,

Wyatt Keller

0 Bhavil Nagar over 2 years ago in reply to Wyatt Keller

Intellectual 365 points

Hi Wyatt,

I tried holding the wake-up button throughout the time that the app was opening. I refreshed once while holding the wake-up button and once without holding it. Both times the result was the same. Below are the screenshots of the dashboard with the error message at the bottom left.

I am connecting a 7-cell configuration with external cell balancing.

0 Wyatt Keller over 2 years ago in reply to Bhavil Nagar

TI__Guru** 105770 points

Hello Bhavil,

The BQ40Z80 does not support 7S systems, please try with a 6S or less setup.

Sincerely,

Wyatt Keller

0 Nikhil Mahajan1 over 2 years ago in reply to Wyatt Keller

Prodigy 20 points

Hello Wyatt

Im working with Bhavil on same project.

we bough the Bq40z80 evm board which we believe supports 7s configuration.

https://www.ti.com/tool/BQ40Z80EVM-020.

0 Wyatt Keller over 2 years ago in reply to Nikhil Mahajan1

TI__Guru** 105770 points

Hello Nikhil,

The EVM could originally support up to 7S, but the firmware had to be adjusted to only support 6S so the BQ40Z80 product age reflects this: https://www.ti.com/product/BQ40Z80

Sincerely,

Wyatt Keller

0 Bhavil Nagar over 2 years ago in reply to Wyatt Keller

Intellectual 365 points

Hi Wyatt,

I tried a 6S configuration and mapped all the EVM pins related to a 7-cell config (CB7EN, V7SENSE, etc) to their alternative, but I am still getting the same error.

+1 Wyatt Keller over 2 years ago in reply to Bhavil Nagar

TI__Guru** 105770 points

Hello Bhavil,

Are you using an external EV2400 or the internal EV2400 on the EVM? Whichever you are using make sure you use the test version of BQStudio and update the firmware on the EV2400 to ensure everything is up to date.

Then make sure to hold the PACK pin above the Vstartup voltage (we have the wakeup button on the EVM) and that the cell configuration is set properly otherwise it will try to keep going to shutdown when the voltage on the PACK pin is removed.

You can also try sending command 0x8 in the advanced comm tab to exit ROM mode if you tried to program the gauge and it failed it could be stuck there.

Sincerely,

Wyatt Keller

0 Bhavil Nagar over 2 years ago in reply to Wyatt Keller

Intellectual 365 points

Hello Wyatt,

Thanks for your time and help. I tried to update the firmware again and after that, the device is working now. Guess something might have gone wrong the first time I did it. I was using the internal EV2400 which is present on the EVM.

Just out of curiosity, why is it recommended to use the test version of BQStudio as I've read this across multiple threads I've been to?

0 Wyatt Keller over 2 years ago in reply to Bhavil Nagar

TI__Guru** 105770 points

Hello Bhavil,

The test version of BQStudio is the most recent release and generally has the most features and bug fixes.

Sincerely,

Wyatt Keller

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BQ40Z80EVM-020: Error with connecting BQ40Z80EVM-020 to Battery Management Studio by TI