PCM1821: Question of Input Offset Specification of PCM1821 ADC

Wayne Chen (Audio AE)

Part Number: PCM1821
Other Parts Discussed in Thread: PCM1804

Hi Sirs,

Would you please advise the input offset specification (Vos) of PCM1821 ADC?
It is not available in current datasheet in public domain - www.ti.com/.../pcm1821.pdf

Thank you and Best regards,

Wayne Chen
05/31/2021

over 3 years ago

0 Zak Kaye over 3 years ago

TI__Mastermind 23050 points

Hi Wayne,

PCM1821 has a fixed digital high pass filter that cannot be disabled, so the Vos is not a useful spec for this device. The gain error will be <1dB though. If you want a HW controlled device that can disable the high pass filter then you might consider PCM1804.

Best,

Zak

0 Wayne Chen (Audio AE) over 3 years ago in reply to Zak Kaye

TI__Genius 15950 points

Hello Zak,

Thank you for your elaborate. Can I say that the PCM1821 is a DC offset free part since there is a built-in high pass filter?

Best regards,

Wayne Chen
06/02/2021

+1 Zak Kaye over 3 years ago in reply to Wayne Chen (Audio AE)

TI__Mastermind 23050 points

Hi Wayne,

Effectively yes because the DC offset of the input PGA and ADC will be filtered out.

Best,

Zak

0 Wayne Chen (Audio AE) over 3 years ago in reply to Zak Kaye

TI__Genius 15950 points

Thank you for your advise, Zak...Wayne Chen

Audio

Audio forum

PCM1821: Question of Input Offset Specification of PCM1821 ADC