Other Parts Discussed in Thread: ADS8881, THS4130
Dear team,
I am using the AFE58JD28 with the THS4130 driving ADS8881 for the CW mode.
1. However, except for the noise requirement, I don't know how to evaluate the GBW requirement of the FDA connecting after the I-Q. I use THS4130 because there are a lots of people using the THS4130 for the ultrasound application.In my opinion , the GBW requirement shouldn't be as higher as 215MHz because the signal of I,Q is about 20Hz to 20KHz and the minimum bandwidth needed to drive ADS8881 is just about 42MHz. Could you please give some rough caculation about how to get the GBW requirement of the FDA? why 215MHz is needed here.
2. what about the other requirement of the FDA in the CW mode, such as (offset, THD,offset drift )? It would be nice if you can also give some rough calculation about these spec based on my application. many things!
Best Regards
Zhihong Huang