TAS6424L-Q1: There is 100k clutter in the output.

Alan Xia

Part Number: TAS6424L-Q1

Hi team，

For TDM, when the customer is playing 1kHz audio, he finds that there is clutter around 100kHz superimposed on the output waveform. At this time, the fault is that the audio is playing and the audio is not playing. I hope BU can help to find out whether this signal is related to DSP or power amplifier 6424L?

OUTPUT:RED AND BLUE

SCLK:YELLOW

SDIN:PINK

over 1 year ago

0 Gregg Scott over 1 year ago

TI__Mastermind 36605 points

Hi Alan,

We will need more information on your test setup.

0 Alan Xia over 1 year ago in reply to Gregg Scott

TI__Expert 5845 points

Hi Gregg,

After today's preliminary troubleshooting and testing with the customer, I attach the current test report and schematic diagram, hoping to help me analyze possible issues. From my current perspective, there seems to be no obvious problem with register configuration. I hope you can help me take a look.SD3A Main Board_V1.1_20230321--AMP.pdf Analysis of Excessive Audio Background Noise in TAS6424--20230321 .docx

0 Yanming Gong over 1 year ago in reply to Alan Xia

TI__Mastermind 19290 points

Hi Alan

Checked the registers, the fault is clock fault.

SNR data was low, but it is not related to 130KHz noise, because the noise is out of audio band.

Do you know the method of SNR test? Did they check noise floor and FFT using AP instrument?

Regards,

Derek

0 Alan Xia over 1 year ago in reply to Yanming Gong

TI__Expert 5845 points

Hi Derek，

1. I have checked the channel registers that reported the error. CH2/CH3/CH4 is because there is no speaker connected, so the three channels will display DC load diagnostics.
2. In addition to using the AP test, do you see any errors such as clocks from the input signal part?

3、At present, the customer also said that the Fault device will be pulled up for a short time when it is powered on, and then it will always be at a low level. At present, I hope to troubleshoot the input problem of the signal? Or register configuration problem? Or is it because of the hardware design of the circuit?