TLV320AIC3104: TLV320AIC3104IRHBR

Hi Santhosh,

Could you share your device tree so that we can see the full code you are working with?

I don't see a problem in hardware that would cause this, but I do have concern about your microphone schematic.

The MICBIAS voltage should be applied to the positive pin only, not in series with the negative pin. Also the signal coming from the mic would be the same phase on the MIC1P as the MIC1N so this would not be a differential signal. The microphone appears single ended from the jack, so MIC1N should be connected to ground.

Best regards,
Jeff McPherson

Dear Jeff,

I have incorporated the changes you suggested earlier. Now, I can hear audio at a very low volume, but I am facing a heating issue with the codec.

Could you please review the attached codec section? We are experiencing very low audio output, and the codec is heating up during song playback. However, no heating issue is observed when the audio is not playing.

Check the below code:

amixer -c tlv320aic3104 sset 'PCM' 100%
amixer -c tlv320aic3104 sset 'HP' 100%
amixer -c tlv320aic3104 sset 'Line DAC' 100%
amixer -c tlv320aic3104 sset 'Left HP Mixer DACL1' on
amixer -c tlv320aic3104 sset 'Right HP Mixer DACR1' on

gst-launch-1.0 filesrc location=/home/root/audio/sample.mp3 ! decodebin ! audioconvert ! audioresample ! alsasink device=plughw:1,0

Please let me know if we are missing anything here.

i.MX8_Codec_Section.pdf

Best regards,

Santhosh

Hi Santhosh,

Normally heating problems are related to layout, not software. Is the thermal pad connected to DRVSS in the layout?

I've also looped in another expert to comment on the amixer codes.

Thanks,
Jeff McPherson

Hi Santhosh, Can you set the "HP DAC" playback volume the same as the Line DAC playback volume? What about the "Line Playback Volume" or "Line Playback Switch" to set the Line Playback on? Are you using alsamixer to show a GUI with available controls or are these controls from somewhere else?

Best,
Mir 

Dear Jeff,

Yes, a thermal pad is provided in the layout for DRVSS (FYR: I have attached an image of the layout below), but the codec is still heating up, and the audio output remains at a very low volume.

Could you please suggest a solution to resolve the heating issue and achieve higher audio output? Additionally, could you review the schematic once again to check if anything might be missing on our side or if there are any potential loading issues?

Looking forward to your suggestions.

Best regards,

Santhosh

4760.i.MX8_Codec_Section.pdf

Hi Santhosh,

Are you able to measure how much current each of the power supplies is delivering to the codec? Our devices are low power and typically don't consume enough power to cause a heating problem.

Also do you have a temperature (case temperature is fine) that the codec is reaching that is making you concerned?

Thanks,
Jeff McPherson

Dear Jeff,

Yesterday, we tested the system by bypassing the audio amplifier, and it seems to be working fine. When using an external amplifier, we are able to get the audio output.

Could you please review the amplifier section? We are measuring a 2.5V signal on the input side, but the output is zero volts, indicating that the amplification is not working. Please let me know whether we are missing anything in amplifier section.

Thanks,

Santhosh

Hi Santosh,

So you are bypassing the TPA2012 or do you mean you have bypassed the headphone outputs from the codec and are using the line outputs to send to the amp? The heating issue is resolved but there's no output from the TPA2012?

The amplifier is supported by a different team so I want to double check that is what you need reviewed before I pass the ticket to them.

Thanks,
Jeff McPherson

Dear Jeff, 

Heating issue is still there while playing song. If I'm not playing song then there is no heating issue. 

Yes, if I bypass TPA2012 and give the input of TPA2012 to external amplifier then I'm able to get the audio output. I'm suspecting TPA2012 is not working. Could you please pass to TPA2012 team and get it reviewed by them? 

Thanks, 

Santhosh

Dear Jeff,

I hope you're doing well. Have you had a chance to review the requests below?

Thanks, 

Santhosh

Hi Santosh,

Our amplifier team has the ticket now and they should follow up soon. It's clear that the TPA2012 is the device that is failing the output audio and is also the device that is heating up.

Thanks,
Jeff McPherson

Dear Jeff,

Please note that the TLV320A codec is overheating during song playback, not the amplifier. When connecting the codec output to an external amplifier, we are able to get audio, but the TLV320A is heating up excessively.

Kindly analyze the issue and provide your suggestions. Let me know if you need any further details from my end.

Looking forward to your response.

Best regards,
Santhosh

Hi Santhosh,

Regarding TPA2012D2 amp:

• Using a scope connected to any of the OUT pins, do you see a Class-D switching signal at all? Please probe before the output filter components, you may try with and without a speaker connected to see if it makes a difference.
• You may have to add a low-pass filter between the Codec output and the Class-D amp input. The noise-shaping of the converter pushes noise out of the audible band, however the Class-D modulation may couple this noise back to the audible range.

What kind of amplifier is the one you use when testing with external amplifier? Is it also Class-D? Do you have the same kind of filter connected at the output of such amplifier as you do for TPA2012D2?
Also, just to confirm, when you use the external amplifier, you have audio at the speaker (out of the amp) however the Codec still heats up? Does the Codec heat up even if you don't connect any amplifier?

Best regards,
-Ivan Salazar
Applications Engineer

Dear Jeff,

Now Amplifier issue is resolved. But TLV320A codec is overheating during song playback, not the amplifier. We are able to get the audio, but the TLV320A is heating up excessively.

Kindly analyze the issue and provide your suggestions. Let me know if you need any further details from my end.

Looking forward to your response.

Thanks & Regards,

Santhosh

Hi Santosh,

Could you provide what the current draw from each of the supplies is going into the codec? You may need to disconnect the other devices to capture this effectively.

Best regards,
Jeff McPherson

Dear Jeff,

I have monitored the current in the 3V3 line, and it is nearly 1.03A, causing the codec to heat up to 60°C. Additionally, the amplifier is also heating up to 40°C.

Could you please suggest what might be causing this overcurrent draw from the codec? Your insights would be greatly appreciated.

Looking forward to your guidance.

Best regards,

Santhosh

Hi Santosh,

The device is certainly damaged. The typical current draw should be in the order of 10s to 100s of mA, not 1A. I would recommend you try swapping devices on the PCB and retest. Take care that ESD does not damage the device.

Best regards,
Jeff McPherson