Question

How the effect of voltage and current drift on the performance of an amplifier is determined?

(a) △VooT/△T = {[1-RF/R1)]×(△Vio/△T)} + RF×(△Iio/△t)

(b) △VooT/△T = {(-RF/R1)×(△Vio/△T)} + RF×(△Iio/△t)

(c) △VooT/△T = {[1+(RF/R1)]×(△Vio/△T)} + RF×(△Iio/△t)

(d) None of the mentioned

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The above asked question is from Thermal Drift in division Operational Amplifier Fundamentals of Linear Integrated Circuits

Answer 1

Answer: (c) ΔVo0T/ΔT = [[1+(RF/R1)]×(ΔVio/ΔT)] + RF×(ΔIio/ΔT)

The output offset voltage drift is determined by the formula that includes both voltage drift and current drift terms, multiplied by their respective circuit gains. The factor [1+(RF/R1)] represents the closed-loop gain of the inverting amplifier configuration, which amplifies both the input offset voltage drift and the input offset current drift.