I found a 16-bit sigma-delta ADC that is separated internally into two sections, a multiplexer and the ADC, all controlled by the same serial connection. Anyways, what basically happens is that the Mux is independent of the ADC, save for the serial protocal control so what happens is that you can connect the output pins on the Mux through a filter before connecting the filter to the input pins on the ADC (rather than just bridging the pins directly). The purpose is to let you use one really good filter for all the channels on the ADC.
I was planning to use this for integrating a few gyro readings, but it just occured to me that suppose I used a filter with a BW of 50Hz, but was planning on "time-splicing" samples across the gyros so that the effective sampling frequency of a single gyro was 100Hz. This would mean that if there were 3 gyros, I would be switching the ADC (and therefore the filter) input at 300Hz. Essentially introducing step changes at 300Hz to the 50Hz filter so that the filter would never be able to respond in time.
Correct? Just asking for confirmation (I'd really like to not have to use 3 separate filters). I'm hoping there's something that I'm missing that would benefit me...but I doubt it. The only thing I can think of is to use a >600Hz filter and don't worry about low-frequency filtering since the sigma-delta ADC will do it anyways...but then I have less control over the bandwidth.
I was planning to use this for integrating a few gyro readings, but it just occured to me that suppose I used a filter with a BW of 50Hz, but was planning on "time-splicing" samples across the gyros so that the effective sampling frequency of a single gyro was 100Hz. This would mean that if there were 3 gyros, I would be switching the ADC (and therefore the filter) input at 300Hz. Essentially introducing step changes at 300Hz to the 50Hz filter so that the filter would never be able to respond in time.
Correct? Just asking for confirmation (I'd really like to not have to use 3 separate filters). I'm hoping there's something that I'm missing that would benefit me...but I doubt it. The only thing I can think of is to use a >600Hz filter and don't worry about low-frequency filtering since the sigma-delta ADC will do it anyways...but then I have less control over the bandwidth.
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