TAS5733L: TAS5733L EVM Setup

Hello, thanks for asking question in E2E.

For line-in audio input mode, please switch to 'Line in' mode in 'Audio I/O' configuration. And apply the analog signal on the AIN1 connector on the mother board. This feature should be working well.

WIth 0dBFS digital input and 2.4dB gain setting in master volume, the output can reach 2*8.5W @ THD+N=10% on the TAS5733L EVM (PVDD=10V, load=6Ohm). Please make sure the AGL is disabled. And try to use 1kHz sinewave as the test input source. Is there any reworking on the board? Did you read the Error Status Register(0x02)? Is there any Fault in it? Basically ther shouldn't any problem in this case.

Best regards,

Shawn Zheng

  

TAS5733LIssue.zipHi Shawn,

Thanks for looking into this for me.  

Attached is a video of the issue that I'm seeing and my project file.

As before, I tried switching to aux in audio and PurePath tells me that the input was switched successfully, but I'm not getting any audio from the line in source.  I was connected to AIN1 and I tried AIN2 as well.  Neither worked.

In the video, the first stepped sweep I did was with the purepath master volume set to 0dB.  The second stepped sweep I did was with master volume set to +2dB.  I see this issue whenever I increase the gain above +0.375dB.  I know the RMS level graph is not outputting any data in the video of the second sweep, but hopefully you can see the scope in the bottom left hand corner is switching between high output and low output.  I checked the error register and it says 0X00, which I took to mean as no error.  I know you asked for a 1kHz input signal instead of a frequency sweep, but the test signal I'm using has 2s of a 1kHz test signal as the first signal out of the file.  This signal as well is not outputting 8W.

There was no rework done on either board.  I have the purepath motherboard and the TAS5733LEVM board.  Both boards are new.  I've only used them 2 times.

I hope this helps you understand what is going on!  I'm happy to answer any other questions you have.

Hi Marshall,
Thanks for the update. The 'Line-in' mode input feature should work well on the TAS533L EVM. Could you please make sure the analog input signal is good? Could you please let me know the revision of your PPCMB? Make sure it's higher than 'D' revision.
Could you please help to measure the PVDD voltage when the issue occurs? This is an open-loop device, so we need to make sure the PVDD power supply voltage is stable.
Best regards,
Shawn Zheng

Hi Shawn,

I've verifier with an Oscope that the analog output I'm putting into the board is 800mVrms. I've plugged this signal into other speakers we have and have gotten audio output from this signal.

For the output power measurement I am using USB audio. That is the only audio path that will work. I have tried Coax, analog as well and neither will work. I have not tried optical as I do not have that capability.

I have checked the power supply as stated in my previous post. The power supply is able to handle jumps in output power quite well. I am not using digital I2S input. I used an Oscope to check the MCLK signal and BCLK signals. They were clean signals, 12.28MHz and 48kHz signals. I checked the error messages and there were no errors in those registers.

As you can see from the attached project file I sent you, the AGL and BQ filters were all disabled. There is no rework done on either board.

Shawn, I'm beginning to be concerned that my eval board isn't working. I need to get this board working ASAP so we can make the decision about whether or not to use this amplifier in all our future products. Is there anyway you or another FAE can get on a call with me about this issue? I need to know if this is my error or a malfunctioning board.

Hi Marshall,
Thank you for the update. Would you please take a photo of your measurement setup? Let's make sure there isn't any setup issue at first. Another thing could be checked is the software revision. Which revision of purepath console are you using? Did you updated the TAS5751M/33L plugin to the latest revision? Do you have another PPCMB and TAS5733L EVM board? Can you repeat the issue with the different board? If you could find the local TI FAE, that would be helpful. They can provide on-site customer support for you. I will still keep following this problem.
Best regards,
Shawn Zheng

Hi Shawn,

I'm using PurePath v3.1.1 Platform build 247.  The revision for the EVM app is: TAS5751M/33L v3.0.2

I've attached a picture of my setup.  The power supply is off screen, but I've already made sure it can provide the 8W of power with no drops in voltage levels.  The Aux in source I'm using is my APx525 analyzer.  I have verified the output of the analyzer is as expected (800mVrms).  

I do not have another eval board I can use.  Can you get me in contact with a local TI FAE that can help me with this?  I'm located in Utah.  

Thanks,

Marshall

Hi Marshall,

Thank you for the info. Looks like there is no problem in your setup. Please note that the analog input connector includes R/L channel. Does your AP support R/L channel in one cable? One simple way is that you could connect the notebook/cellphone headphone output to the PPCMB input(AIN1) by a cable(shown in the below picture). Let me know if it works. I will call you if it still doesn't work.

Best regards,

Shawn Zheng  

Hi Shawn,

Sorry it took me a while to get this info, but I probed the input to the ADC on R229, R231 and saw the sine wave I was inputting to AIN1.  The connector and input signal are working as expected and this includes L/R channels.  I then probed R279 as the output of the ADC and did not see any digital data out.  There was no data out of the ADC, so I believe that the board is not working as expected.

Let me know your thoughts.  Thanks,

Marshall