Q.53 In an N bit flash ADC , the analog voltage is fed simultaneously to
comparators. The output of the comparators is then encoded to a binary format using digital circuits. Assume that the analog voltage source
(whose output is being converted to digital format) has a source resistance of 
as shown in the circuit diagram below and the input capacitance of each comparator is 8 pF. The input must settle to an accuracy of 1/2 LSB even for a full scale input change for proper conversion. Assume that the time taken by the thermometer to binary encoder is negligible.
If the flash ADC has 8 bit resolution, which one of the following alternatives is closest to the maximum sampling rate?
(A) 1 megasamples per second
(B) 6 megasamples per second
(C) 64 megasamples per second
(D) 256 megasamples per second
Answer: (B)
Explanation:
