I want to measure delay between input and output in sample by sample processing in DSP system. The system is something like this.
ADC --> MUX --> DSP21479 --> DAC
The Use of MUX in the system is to select one among the different inputs.The MUX i am using is ADG1404. The truth table of the MUX is
EN A1 A0 S1 S2 S3 S4
0 X X Off Off Off Off
1 0 0 On Off Off Off
1 0 1 Off On Off Off
1 1 0 Off Off On Off
1 1 1 Off Off Off On
I have enabled MUX in my system and made it as static. i.e always state S1will be selected(A1 =0 A2 =0).
I am running sample by sample system and ADC, DAC are running at 800KHZ. With this rate i am expecting as maximum of two samples delay(i.e 2.5usec) from input to output. But when i measure the delay i am getting around 7.5 usecs.( i.e 6 samples).
I am not sure from where these extra four samples of delay is coming from.
WIll there be any delay because of MUX.