AD9375 SYNCOUT_B is from HI to Low, when change TXATT to 0dBFS from -2dBFS with 0dBFS digital input

Hi all,

Our customer evaluate AD9375 EVB + Aria 10 .

Evaluating TX performance with PA,DPD off,

SYNCOUT_B is from HI to Low, when change TXATT to 0dBFS from -2dBFS with 0dBFS digital input.

TXATT at -2 dBFS or less is normal operation.

What is happening ?

In the datasheet @ AD9375 Rev. 0 Page 10, following noted.

8 Note that the input signal power limit does not correspond to 0 dBFS at the digital output because of the nature of the continuous time Σ-Δ ADCs.

Unlike the hard clipping characteristic of pipeline ADCs, these converters exhibit a soft overload behavior when the input approaches the maximum level.

What is the " a soft overload behavior " ?

But we do not understand why require to reset the link with SYNCOUT_B ?

Please advices to us !

Best regards,

sss



additional
[edited by: sss@jpn at 9:05 AM (GMT 0) on 15 May 2019]