PCM1773: Zero detect function.

Kuramochi Tadahiko

Guru 28715 points

Part Number: PCM1773

Hi,

Does PCM1773 have zero detect function?

Because, the offset voltage occur after about few ms from when 0x0000 data is inputted.

And the offset voltage disappear just before next data is inputted.

I guess that this offset is caused by zero detect function.

When the data other than 0x0000 is inputted, the offset voltage doesn't occur.

If it doesn't have zero detect function, what is this offset voltage caused by?

Best Regards,

Kuramochi

over 7 years ago

0 Kevin Duke over 7 years ago

TI__Mastermind 46290 points

TQ,

TQ said:

Because, the offset voltage occur after about few ms from when 0x0000 data is inputted.

And the offset voltage disappear just before next data is inputted.

What is the "next data" in this case and how is the offset being measured in that situation?

0 Kuramochi Tadahiko over 7 years ago in reply to Kevin Duke

Guru 28715 points

Hi Kevin-san,

Thank you for your help.

Could you see the attached file?

PCM1773.xlsx

Best Regards,

Kuramochi

0 Paul_Frost over 7 years ago in reply to Kuramochi Tadahiko

TI__Guru 54903 points

Hi Kuramochi-san,

This is the device entering and exiting the zero input mute mode. When their is no input data, the device will disable the offset calibration to save power. Unfortunately on the this device, the auto-mute cannot be disabled. In the past we have recommended that customers apply a 1 LSB offset to their data input (so at idle the code is 0x000001) if they do not want to see the offset change.

Thanks!
Paul

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PCM1773: Zero detect function.