I'm still learning the intricacies of electronics and though I have accomplished some basic tasks, circuit design is still daunting. I have an accelerometer and would like to know if the ADC I have chosen is appropriate.
Specifically the idea of my input's impedance is not clear to me. I know it relates to the current my signal can produce but I can't figure out how to calculate the necessary/available current from the data sheets.
I plan to sample the sensor at 12kHz (2x the output frequency). I think the suggests that my clock will run at about 1MHz (24bit x 12kHz).
Additional points of confusion:
- The natural frequency of the Accelerometer is 6000Hz, Does this refer to all three channels refreshing at 6000Hz or will the refresh rate be distributed among each channel (XYZ = 2000Hz effective)?
- I need to oversample the signal by 2x I think, so a similar question follows for the ADC. Does the 100ksps get distributed among each analog input, or can I sample all 4 inputs at 100ksps?
References and corrections are welcome!
Edit: It is an expensive sensor because I am trying to characterize an impact on the order of 500g and with duration of 3ms. For a CV of 10% I need about 10 samples in that time which is 3kHz. If a cheaper sensor exists I will gladly use it.