TAS2781: Calibration error and Characterization

Hi, Je Sang, 

apologies for the delay, Shall respond in 12 hrs

Regards,
Arthur

Hi, 

1) the cal.bin file is the calibrated speaker parameters that are obtained from the factory calibration tool. it will not be generated from PPC3.

2) you will need to perform speaker characterization in PPC3 to get the speakers thermal parameters, this will be done using the smart amp learning board, and the PPC# . https://www.ti.com/product/PP-SALB2-EVM/part-details/PP-SALB2-EVM? 

3) Calibration is needed to find the speakers Re, this is used to calibrate the speaker thermal protection. the thermal protection will know the speakers temperature by measuring the speakers Re and since the Re will change by 0.33%/degreeC a small difference in the baseline Re can lead to many degrees of inaccuracy in the protection. it should still be possible to get a good speaker output without calibration(i.e. you shouldn't get 0.4W from a 12W speaker) , but the speaker may be over or under driven.

4) you can create a configuration in ROM mode which will bypass the protection and calibration for evaluation.

5) For the version of PPC3 that you have this cannot be done. I am checking with the PPC3 team to see if I can share a beta version which can accomplish this. otherwise i will help support you in providing the files.

Regards,
Arthur

Hi, Arthur

Thank you for your answers.

I also have questions as below.

1) Where can I get the factory calibration tool and the manual for the tool?

2) The document of PP-SALB2-EVM does not include detailed explanations about the speakers thermal parameters.

    Is there any detailed manual for characterization, calibration, and thermal parameters, respectively?

3) I used the default characterization value in PPC3.

    I found that the integral gain1, integral gain2, and proportional gain were the main cause for 0.4W outputs.

    I changed integral gain1 from 0.0125dB to 0.125dB, integral gain2 from 0.2dB to 2dB, and proportional gain

    from 0.05dB to 0.5dB.  The output increased to 11.1W from 0.4W.

   I’ll try to tune the speaker correctly with time.

4) In ROM mode, I can get the 12W output.

5) Could you tell me when can I get the beta version or the files?

Regards,

Je Sang

Hi Je Sang, 

I am checking on the following for you

1) how to provide FCT tool, 

I have confirmed that the new PPC3 version which will support both characterization without LB2(only EVM is needed for Characterization) and the ability to disable smart amp protection/characterization while maintaining the EQ/DRC and other audio enhancement functions. This is scheduled to be released to the public and the end of this month. I would ask you wait until then before we can share it.

In general you are correct that PG, IG1, IG2 are determining the output power to the speaker. increasing these gain values in the way that you did will increase output power, but this should be done carefully as increasing these gains too much can cause pumping and other audio fluctuations

Regards,
Arthur

Hi, Arthur

Thank you for your answers.

I'll look forward to the release of the new PPC3 version.

I'll test it with the new PPC3 version and get back to you.

Regards,

Je Sang

Hi, 

The FCT tool for Linux TAS2781 can be downloaded from the below git

CGit @ Texas Instruments - Open Source Git Repositories - git.TI.com/cgit

Regards,

Arthur

Hi, Arthur

Thank you for your answers.

I'll check with it and get back to you.

Regards,

Je Sang

Je Sang, 

Let me know if you face any issue.

and to confirm once again we can share the updated ppc3 near the end of this month. perhaps in 1-2Wks

Hi, Arthur

I downloaded the tas2781-linux-drivers/tas2781-ftc revision code, built it after settings

, and ran it on the device, but it failed with error messages.

What more variables do I need to modify for it to work?

Is there any more data needed when running the program?

Please let me have your advice on why the error occurs.

I'm waiting for the updated PPC3.

Regards,

Je Sang

Hi Je Sang,

I will check if there is a user guide or some guidance on this particular tool. 

in addition I will check on ppc3 availability.

regards,

Arthur 

Hi Je Sang, 

Have you referenced the "Guideline for Integrated SmartAMP FTC"  PDF included in the files?

Regards,

Arthur

Hi, Arthur

I referred to the "Guideline for integrated SmartAMP FTC" in the files, but didn't succeed.

Regards,

Je Sang

Hi Je Sang, 

Understood. I am reaching out to our software team to support you on this. 

Regards,
Arthur

Do not modify the definition of TILOAD_NOD, our driver code will created a misc driver node as TILOAD_NOD for calibration. Thanks.

Hi, Arthur

It seems that there is no updated version of PPC3 in the product information.

Please let me know when the PPC3 next version will be available?

Regards,

Je Sang

Hi Je sang, 

We are still testing the version before release, I have asked for updated timeline from the PPC3 team

Regards,
Arthur

Hi, Arthur

Thanks. I'm looking forward to the release of the new PPC3 version.

Regards,

Je Sang

Hi, Shenghao

I got the tas2781-ftc file and put it in the src folder.

I created the tas2781-ftc file by running the ‘make’ command.

Then, copy the created binary file to the board which has tas2781 chip.

I put it in and ran it, but error messages appeared as below.

It didn’t work.

What is silence.wave, where can I get the file?

What I want is to get the tas2781-0x3d-cal.bin file. How can I make it?

You told me not to change Tiload_node, but it made errors.

Please let me know how to make the tas2781-0x3d-cal.bin file without errors.

Regards,

Je Sang

Pls confirm whether the /dev/tiload_node has been created in your system?