Part Number: TLV320AIC3106EVM-K
I have procured an evaluation board of Tlv320aic3106.
I will be attaching a coil mic to it and expect to sample at a rate of 8kHz. I have checked the output range of my coil mic (2mV to 10mV) Vpp.AUDIO CODEC DATA ANALYSIS.docxClick here to play this audio clipClick here to play this audio clipI acquired samples (sound recorder in Windows 7) using PC in .wav format.following were my configurations for codec to capture inputMIC3R input on audio codec (LADC active) Level (attenuation set to 0db)PGA set to 0db
Sampling freq default 44.1kHz
and fed following range (3mV to 500mV) 1kHz tones.On analyzing the captured input. Results attached ....I can receive 50mV with wave shape maintained as shown in doc ..... below 50mV inputs waveshape looks unrecognizable negative swing missing....Applying 500mV gives a clear swing, for lower voltages (below 50mV) no much negative swing seen....For 500mV SINAD is lowI tried applying PGA of 20dB to lower voltages 3mV to 50mV here to lower voltages though receive higher amplitude has no tone content for voltages below 50mV.
I later modified the input with low pass filter of 4kHz bandwidth but of no use.I am unable to identify what is the issue. Is this noise inherent at chip input?? Chip data sheet points to a dynamic range of 91db.Is it board induced noise overcoming weak input signals.?? Does it mean I need to amplify the signal before sending to codec??
We are glad that we were able to resolve this issue, and will now proceed to close this thread.
If you have further questions related to this thread, you may click "Ask a related question" below. The newly created question will be automatically linked to this question.
In reply to Steve-Wilson:
How to capturevregister configuration??..... yes i an acquiring audio using USB
In reply to Rakesh Muralidharan:
As you said there was an issue with the setup,test results for Ti(1).xlsx the ground connection was flimsy . Now I have resolved the issue and captured data.
Data sheet claims to offer dynamic range of 91db. Attached is my result.
What is the level for full scale?? is it 200mVp-p.
during my observation from test result 3660.test results for Ti(1).xlsx i could observe a drop in SINAD for input voltages above 200mV. This as i understand is due to increase in harmonic components. upto 200mV SINAD was good.
how to obtain the aforesaid dynamic range. If i consider 200mV as my distortion less peak signal my dynamic range is about 70dB. There is still plenty of room for improvement.
PLease let me know the fullscale for codec and reason for distortion above 200mV is it expected?? Please let me know
All content and materials on this site are provided "as is". TI and its respective suppliers and providers of content make no representations about the suitability of these materials for any purpose and disclaim all warranties and conditions with regard to these materials, including but not limited to all implied warranties and conditions of merchantability, fitness for a particular purpose, title and non-infringement of any third party intellectual property right. No license, either express or implied, by estoppel or otherwise, is granted by TI. Use of the information on this site may require a license from a third party, or a license from TI.
TI is a global semiconductor design and manufacturing company. Innovate with 100,000+ analog ICs andembedded processors, along with software, tools and the industry’s largest sales/support staff.