A/D Group Delay
I want to use NAI A/D modules for real-time control application, so low-latency is critical. Is there any way to reduce group converter delay?
Use an A/D module that has a dedicated Sigma-Delta (or sometimes Delta-Sigma) A/D converter on each individual channel. Inherent to the Sigma-Delta design implementation is an oversampling delay on the input to produce the first digital conversion. (Subsequent data samples occur at the programmed sample rate.) At a 200 kHz sample rate, the group delay is approximately 6 samples (i.e. group delay = (6) x 5 µs = 30 µs). This cannot be reduced.