TLV320AIC3100: Headphone outputs(HPL/R) are inverted against inputs

Hirotaka Matsumoto

Part Number: TLV320AIC3100
Other Parts Discussed in Thread: TLV320AIC3101

Hi all

Would you mind if we ask TLV320AIC3100?
It seems that headphone outputs(HPL/R) are inverted against inputs..
The conditions are follows;
INPUT : MIC1LP only with single end
OUTPUT : HPL/R, the setting is lineout driver(P1R44[D2-1])

So, is there any un-inverted setting using register?
In addition to this, TLV320AIC3101(headphone outs(HPLPUT/HPROUT) had the same problem.
As the result of this, mixer circuit after DAC inverts signal.

Kind regards,

Hirotaka Matsumoto

over 6 years ago

0 Sadanori Kato over 6 years ago

Guru 36540 points

Hi Matsumoto-san,

It is possible to invert the polarity of the output using the internal biquad filter, but is it reasonable for your customer to apply it?

Best regards,
Kato

0 Sadanori Kato over 6 years ago in reply to Sadanori Kato

Guru 36540 points

Hi Matsumoto-san,

The additional information is shown as follows.

It is possible to invert the polarity of the output if the following coefficients can be applied to the biquad filter.
According to TLV320AIC3100 data sheet, it may not be reflected even if setting 0x8000 to N0.
So, I'm looking forward hearing from TI experts.

N0 = 0x8000
N1 = 0x0000
N2 = 0x0000
D1 = 0x0000
D2 = 0x0000

Best regards,
Kato

0 Hirotaka Matsumoto over 6 years ago

Guru 27585 points

Hi team

If you have any update, could you share us?

Kind regards,

Hirotaka Matsumoto

0 Hirotaka Matsumoto over 6 years ago

Guru 27585 points

Hi team

We guess that your days are so busy, however could you let us know?

Kind regards,

Hirotaka Matsumoto

0 Ravi Patil over 6 years ago in reply to Hirotaka Matsumoto

TI__Expert 5645 points

Hi Matsumoto-san,

Apologies for the delay as I had not received the email for this post.

I'll look into this query and will have an update in a day or so. Thanks.

Best regards,

Ravi

0 Hirotaka Matsumoto over 6 years ago in reply to Ravi Patil

Guru 27585 points

Ravi san

Thank you for your copertation always.

If you have some update, could you give us?

We appreciate your help always.

Kind regards,

Hirotaka Matsumoto

0 Hirotaka Matsumoto over 6 years ago in reply to Ravi Patil

Guru 27585 points

Ravi san

We are sorry to hurry you, our customer needs this reply by next Monday.
We need your help always.

Kind regards,

Hirotaka Matsumoto

0 Steve-Wilson over 6 years ago in reply to Hirotaka Matsumoto

TI__Mastermind 30210 points

Matsumoto-san,

I'm afraid Ravi is out ill. I have done some initial investigations into your issue and I am able to reproduce your problem when using the default processing block. However, if I change to processing block 23, the inversion goes away. I will need to consult with the design team to understand why this is the case, but if the customer is not particularly attached to a particular processing block, Use processing block 23.

best regards,
-Steve Wilson

0 Hirotaka Matsumoto over 6 years ago in reply to Steve-Wilson

Guru 27585 points

Steve san

Thank you so much for your reply!

However, if I change to processing block 23, the inversion goes away.
->We are sorry that we could not understand correctly. What does "processing block 23" mean?

   Enable FIR filter.                              Table 7-17. ADC Processing Blocks
   Set File filter coefficient’s                 Table 7-20. ADC FIR Filter Coefficients
   F0      = 0x8000               (-1)
   F1~24 = 0x0000

Kind regards,

Hirotaka Matsumoto

0 Steve-Wilson over 6 years ago in reply to Hirotaka Matsumoto

TI__Mastermind 30210 points

Matsumoto-san,

The TLV320AIC3100 has built-in digital audio processing blocks (PRB) for both the DAC and ADC paths.

see Data sheet section 7.3.9.4.1 for the ADC Processing Blocks and section 7.3.10.1.1 for the DAC Processing Blocks

I was specifically referring to the DAC processing blocks as my understanding of the problem was that data you were providing to the digital input was being inverted on the analog output. I can duplicate that. I found however that by using processing block 23, the signal was not inverted. I need to reach out to the design team to see why this is the case, but it didn't seem as though the customer was especially concerned with the processing blocks, So if it is all the same to them, just use processing block 23.

best regards,

-Steve Wilson

0 Hirotaka Matsumoto over 6 years ago in reply to Steve-Wilson

Guru 27585 points

Steve san

Thank you for your reply!

OK, we got it.
We will inform our customer.

Kind regards,

Hirotaka Matsumoto

0 Hirotaka Matsumoto over 6 years ago in reply to Steve-Wilson

Guru 27585 points

Steave san

We would like to confirm one point.

In case of PRB_R4 or PRB_R16, it seems that FIR coffecient is ignored.
So, in case of these, the signal was not inverted, or inverted?
And then, we are waiting for your design team's advice.

Kind regards,

Hirotaka Matsumoto

0 Hirotaka Matsumoto over 6 years ago in reply to Steve-Wilson

Guru 27585 points

Steve san

Could you let us know your circumstance?

Kind regards,

Hirotaka Matsumoto

0 Steve-Wilson over 6 years ago in reply to Hirotaka Matsumoto

TI__Mastermind 30210 points

Matsumoto-san,

I apologize for the delays, The design team is very busy. I have sent an urgent request to them to clear this up, and expect a reply soon.

thank you for your patience.

bet regards,
-Steve Wilson

0 Hirotaka Matsumoto over 6 years ago in reply to Steve-Wilson

Guru 27585 points

Steve san

Thank you so much for your reply!

We appologize that we make you hurry up.
OK, we got your circumstance.
We are waiting for your reply!

Kind regards,

Hirotaka Matsumoto

0 Steve-Wilson over 6 years ago in reply to Hirotaka Matsumoto

TI__Mastermind 30210 points

Matsumoto-san,

Unfortunately I don't have a particularly clear answer on this. It is true that some of the processing blocks invert the audio signal, and some do not. Using the BiQuad filters to invert the signal is always a possibility and for that reason it was acceptable.

best regards,
-Steve Wilson

0 Hirotaka Matsumoto over 6 years ago in reply to Steve-Wilson

Guru 27585 points

Steve san

Thank you for your cooperation.

OK, we got it.
And then, we will close this content using your comment.

Kind regards,

Hirotaka Matsumoto

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TLV320AIC3100: Headphone outputs(HPL/R) are inverted against inputs