DAC specifications: Is the relative accuracy (static linearity) of a digital-to-analog converter determined by its settling time specification?

Introduction / Context:
Digital-to-analog converters (DACs) have static and dynamic performance metrics. This question distinguishes relative accuracy (a static linearity measure) from settling time (a dynamic time-domain measure), preventing confusion when reading datasheets or selecting parts.

Given Data / Assumptions:

• Relative accuracy is commonly specified as integral nonlinearity (INL) in LSBs.
• Settling time is the time for output to enter and remain within a specified error band after a code step.
• Different DAC architectures exhibit different dynamic behavior, but static linearity definitions are universal.

Concept / Approach:
Relative accuracy (linearity) quantifies how closely the DAC’s transfer function matches an ideal straight line across the full code range. Settling time addresses how fast the DAC output approaches its final value after a step. These are orthogonal characteristics: a DAC can be very linear (good relative accuracy) yet slow to settle, or fast-settling but with poor linearity.

Step-by-Step Solution:

Verification / Alternative check:
Check any DAC datasheet: INL/DNL (static) appear in the accuracy section; settling time in the dynamic characteristics section. Values change with architecture and load independently, confirming the separation.

Why Other Options Are Wrong:

Common Pitfalls:
Equating “within ±0.5 LSB after t” to overall accuracy; ignoring thermal drift and reference accuracy; assuming faster is always more accurate.

Final Answer:
Incorrect