LTC2500-32 step response figure29 in the datasheet

My customer asked me some question on Figure29 in the LTC2500-32 datasheet.

1.  what is output sample number(horizontal axis)?

2. what does D1(n) mean? DF=1?

3. what is theDF setting for LTC2500-32 OUTPUT SAMPLES DOUT(k) ?

4. would you expalin what SINC1 FILTER OUTPUT D1(n) line and x shows?

   and why ithe vertical value is 3/4 when the horizontal value is 1 and the vertical value is 2 when

   the horizontal value?

 does this mean it's 2 stage FIR filter with the first coefficient is 3/4 and the second coefficient is 1/4?

  • 0
    •  Analog Employees 
    on Nov 30, 2020 3:51 PM

    1. output sample number is the number of data outputs the ADC has provided

    2. D1(n) is the filter response where n is the output sample number

    3. The response is independent of the DF

    4. For SINC1 output the first sample after the step input signal would be approximately 3/4 of the final value. The filter has latency so it doesn't settle instantly. By the second sample the filter should have settled. All following samples will provide the same value.