What to do with unused audio inputs on the TLV320AIC3101 codec?

Chris Parks

Other Parts Discussed in Thread: CC8520, TLV320AIC3101

I'm using the TLV320AIC3101 with the CC8520 Purepath wireless audio ic. In my design, I have a mono input routed to the MIC1LP/Line1LP.

In the cad program I'm using, (Cadsoft Eagle) I can not leave the unused inputs not connected to something without getting an Error in the Error Checking.

I thought I would connect the following signals to audio ground. Will this work?

MIC1LM/LINE1M, MIC1RP/LINE1RP, MIC1RM/LINE1RM, MIC2L/LINE2L/MICDET, MICBIAS, MIC2R/LINE2R

I appreciate any suggestions you may have.

over 11 years ago

0 Don Dapkus over 11 years ago

TI__Guru**** 189399 points

Hi, Chris,

You should be able to power down all those pins via registers so you can connect them to ground. Please check the d/s for more details.

Otherwise, you could AC ground them thru a cap, but I realize you probably don't want to put an extra six caps if you don't need to.

I checked the MICBIAS, and it says on Page 40 of the d/s that it can be disabled via register 25 in page 0 of the I2C register bank.

-d2

0 Converter Apps over 11 years ago

TI__Mastermind 28585 points

Hi Chris,

It is best to AC couple the inputs to audio ground if they are not used. They can also be left floating. Directly grounding these pins can lead to problems before and during reset or if an improper reset is done.

0 Chris Parks over 11 years ago in reply to Converter Apps

Prodigy 50 points

Thanks for the answer to my question. I've connected those audio inputs to analog ground through capacitors.

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What to do with unused audio inputs on the TLV320AIC3101 codec?