Search FAQs on the left to see if your question has been answered. Click on the dropdown to view all of the documents associated with the product. If you can't find your question, click on Ask a Question

AD2S80A_closed loop bandwidth

How could I choose the closed-loop bandwidth (fBW with the AD2S80A
Are there guidelines.
Resolution                 Ratio of Reference Frequency/Bandwidth
10                              2.5 : 1
12                              4 : 1
14                              6 : 1
16                             7.5 : 1
Could you please help to give some comments on it? Thanks.


That section is a little confusing I agree.

The data sheet states,
5. Closed-Loop Bandwidth Selection (C4, C5, R5)
a. Choose the closed-loop bandwidth (fBW) required
ensuring that the ratio of reference frequency to bandwidth
does not exceed the following guidelines:
Resolution Ratio of Reference Frequency/Bandwidth
10 2.5 : 1
12 4 : 1
14 6 : 1
16 7.5 : 1
Typical values may be 100 Hz for a 400 Hz reference frequency
and 500 Hz to 1000 Hz for a 5 kHz reference frequency.

This would be better interpreted as choose a bandwidth at least the ratios
For example with 12 bits resolution and a 5 kHz reference frequency the
bandwidth should be 1.25kHz maximum but down to 500Hz or a 10:1 ratio should be

If the customer continues to have trouble determining the component values I
can provide some assistance or I suggest the component selection program. It
can be found at
if you scroll down through the text.