Relative complexity and speed: A/D versus D/A conversion When comparing digital-to-analog (D/A) and analog-to-digital (A/D) conversion processes in general-purpose systems, which statement is typically true?

Introduction / Context:
D/A and A/D conversions bridge the analog and digital worlds. DACs reconstruct an analog level from a code, whereas ADCs must decide the correct code from an analog input. The direction of conversion strongly affects design complexity and time behavior.

Given Data / Assumptions:

• We compare common, mainstream architectures (e.g., R-2R DACs; SAR, sigma-delta, flash ADCs).
• We consider typical resolution ranges (8–16 bits) and moderate speeds.

Concept / Approach:
DACs generate an output by summing weighted elements; the operation is instantaneous aside from settling time. ADCs must measure and decide between many possible codes, requiring successive approximation, oversampling/noise-shaping, or many comparators; these processes take more time and control logic, making A/D generally more complex and slower for a given technology and accuracy.

Step-by-Step Solution:
Recognize that ADCs perform a search or average to determine the correct code.These actions consume clock cycles (SAR) or long integration/decimation (sigma-delta) or large hardware (flash).DACs primarily settle to a value; no code search is required.Therefore, A/D is typically more complicated and more time consuming than D/A.

Verification / Alternative check:
Compare datasheets: for comparable resolution, DACs often achieve faster update rates than ADCs achieve sampling rates, barring specialized architectures.

Why Other Options Are Wrong:

• Less complicated/time consuming: Contradicts the need for decision processes in A/D.
• More complicated but less time consuming: Rarely true outside of niche, very-high-speed flash vs. slow DACs.

Common Pitfalls:

• Assuming “fast ADCs exist, so A/D is always faster”—context matters; for mainstream use, A/D tends to be the bottleneck.

Final Answer:
more complicated and more time consuming than the D/A conversion.