GATE 2025 IN – Question 34
A dual-slope ADC has fixed integration time 100 ms and reference voltage −5 V. Its total time to measure an input of 1.25 V is ______ ms (rounded to the nearest integer).
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Correct answer: 125 to 125
Explanation
Integrator charge balance gives $V_{in}T_{int}=|V_{ref}|T_{deint}$, so $T_{deint}=1.25(100)/5=25$ ms.
The conversion includes both intervals: $T_{total}=100+25=\boxed{125\ \mathrm{ms}}$.