TLV320AIC3120EVM-U: Regarding Noise issue with ELECTRET CONDENSER MICROPHONE.

Hi,

Can you clarify, when recording and playback at the same time, the playback audio is coupling back onto the recording path? Or are you experiencing noise on the recording path regardless. What is the profile of the noise you are measuring? 

Thanks,
Jeff McPherson

Hi,

Thanks for your reference, we experimented recording and playback separately. I am experiencing noise in the recording path. I didn't have any noise level data with me, but we are experiencing a white noise sound effect from the speaker along with the recorded audio.

Hi,

Even in environments we consider quiet to our ears, microphones pick up any kind of noise, so it's not unusual to get white noise. This is especially true since the EVM has no noise conditioning circuits on the input pins. 

However without noise level data I cannot say if it's expected or not. I would compare using a signal generator, which is much cleaner, on the input to see if the noise remains or if it is unique to microphones. 

Best regards,
Jeff McPherson

Hi Jeff McPherson,

I can understand that white noise is unavoidable, since recorded Audio's amplitude itself very low, can you suggest some technique to increase the recorded audio amplitude, with below mentioned specification of mic

MIC.pdf

Hi Jeff McPherson,

Thanks for your Response, we have experimented with maximum ADC Gain of mic, even though we can't achieve a significant level of amplitude gain from the Mic. I understood noise can't be avoided, we are ok with that, kindly suggest any other methods to increase the amplitude of Mic's output. or suggest any specifications of mic which will be suitable for audio recording with TLV320AIC3120 Series.

Hi,

Can you measure the output of the microphone? What RMS voltage are you getting?

Also have you connected the condenser mic to some kind of power source such as MICBIAS?

Best regards,

Jeff McPherson