DAC gain error definition In the context of digital-to-analog converters, what is meant by “gain error”?

Introduction / Context:
DAC static errors are commonly categorized as offset, gain, differential nonlinearity (DNL), and integral nonlinearity (INL). Correctly identifying them is vital for precision analog design.

Given Data / Assumptions:

• “Gain error” concerns the scale of the transfer function, not its intercept and not step-to-step irregularities.

Concept / Approach:
Gain error measures how the actual slope of the DAC transfer curve differs from the ideal slope after removing any offset error. It effectively scales all codes up or down relative to ideal.

Step-by-Step Solution:
Remove offset by aligning the first code (typically zero) to ideal.Compare the span between zero-scale and full-scale actual outputs to the ideal span.A difference in span (slope) is the gain error.

Verification / Alternative check:
Datasheets often specify gain error in LSB or percent of full scale, separate from offset and linearity specifications.

Why Other Options Are Wrong:
Missing codes: a DNL/monotonicity problem.First step needs different input: that is offset error, not gain.Nonmonotonic behavior: separate monotonicity failure, not a gain slope issue.Settling time: a dynamic (timing) specification.

Common Pitfalls:
Mixing offset and gain errors; remember offset shifts the curve, gain tilts it.

Final Answer:
error in the slope of the output staircase waveform