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Question 29.11: If a 10-bit Flash converter is designed, determine the maxim......

If a 10-bit Flash converter is designed, determine the maximum offset voltage of the comparators which will make the INL less than ½ LSB. Assume that the resistor string is perfectly matched and V_{R E F}=5~\mathrm{V}.

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Equation (29.48) requires that the offset voltage equal ½ LSB. Therefore,

| IN L|_{m a x}=\frac{V_{R E F}}{2}\cdot\left|\frac{\Delta R_{k}}{R}\right|_{m a x}+\left|V_{o s,i}\right|_{m a x}               (29.48)

\left|V_{o s}\right|_{m a x}=\frac{5}{2^{11}}=2.44\;\mathrm{mV}

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