Correct Answer - Option 4 : 4 μs
Concept:
The conversion time of different types of ADC is shown :
Type of ADC
|
No. of Clocks
|
Time
|
Counter Type
|
2n-1
|
2n-1 Tclk
|
SAR
|
n
|
nTclk
|
Flash
|
1
|
Tclk
|
Dual Slope
|
2n+1
|
2n+1 Tclk
|
From the above table, it is clear that the dual-slope is the slowest ADC and Flash Type is the fastest ADC.
Calculation:
Number of bits (n) = 8
Frequency (f) = 2 MHz
Time period, \(T = \frac{1}{f} = \frac{1}{{2 \times {{10}^6}}} = 0.5\;\mu s\)
Conversion time (Tconv) = nT = 8 × 0.5 μs