How different integration times affect the noise performance of the DDC?

Hi,

Basically in charge terms, different integration times do not affect the final noise (see the specific DDC datasheet). Nevertheless, they certainly do change the response bandwidth and if there are external noise sources (like the resistor on this app note example or just external interferers), there could be different results. See the same app note for an explanation on the gated integrator (DDC input circuit) bandwidth response. Still:

1. If the board is designed properly to reduce external noise sources, one should see no difference.
2. If one chooses to sample faster a signal that is slow, one could still apply digital filtering to remove the external higher frequency (off-signal) noise sources…

Regards,

Eduardo