TLV320AIC3254 Not getting Mic Data through I2S

Linto Antony

We are able to make the speaker work ,we are getting the triangular wave what we are feeding to the codec through the I2S lines.Now issue is when we configure Mic(IN2 lines to codec chip)mono mic jack to receive data through I2S we are not getting any data. For your reference we are attaching the configuration we used for the MIC for your reference.

Note:

1. 16 bit PCM data at 16KHz sampling rate

2. BCLK = MCLK = 768 KHz

3. IN2L is not populated in schematics,we have only IN2R and MICBIAS lines going to codec chip from the MonoMic Jack

over 11 years ago

0 Don Dapkus over 11 years ago

TI__Guru**** 189401 points

Hi, Linto,

Sorry for the delay in getting back to you.

We have a holiday in the US right now, so it will be next week until someone can look into your question.

Did you make any progress yet?

-d2

0 Linto Antony over 11 years ago in reply to Don Dapkus

Prodigy 35 points

Hi Don,

We are able to bring-up LINE IN and Mono Jack MIC with the configuration I am attaching in the post. But with this

we are observing lot of noise even when we are not playing anything via LINE-IN or Mono Mic and when we start

playing we get more noise as we increase the volume.

Now need help to reduce the Noise , please provide the configuration we have to use to reduce the noise.

Note:

1. we are using 16Khz , 16bit ,Stereo with MCLK =BCLK=512Khz .

2. Attached excel sheet have the working configuration. We use either Line In or Mono MIC but not both together.1488.LINE_IN_MONO_MIC_AIC3254_Codec_Configuration.xls

0 Don Dapkus over 11 years ago in reply to Linto Antony

TI__Guru**** 189401 points

Hi, Linto,

Did you get this sorted out? Sorry I missed your reply.

-d2

0 Linto Antony over 11 years ago in reply to Don Dapkus

Prodigy 35 points

Hi Don,

We tried experimenting with the AGC registers but there was no good reduction in noise , we then tried to use

the DRC setting in the codec data sheet and now we are able to get noise reduced to good extent.

Thanks and Regards,

Linto

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TLV320AIC3254 Not getting Mic Data through I2S