DAC settling time definition In data converter specifications, settling time is normally defined as the time required for the DAC output to settle within ________ of its final value after a code change.

Introduction / Context:
Settling time characterizes how quickly a DAC’s output reaches and remains within a specified error band after a digital code transition. The error band is typically expressed in terms of least significant bits (LSB).

Given Data / Assumptions:

• Standard industry practice uses a 1/2 LSB error band for “within final value.”
• Measurement includes the effects of slewing, ringing, and residual error.
• Final value is the ideal analog output corresponding to the new code.

Concept / Approach:
A 1/2 LSB window ensures that, once settled, the output is unambiguously closer to the target code than to any adjacent code. This aligns with quantization boundaries and typical converter accuracy definitions.

Step-by-Step Solution:
Define LSB step size → full-scale / 2^N.Settling → time until output remains inside ±0.5 LSB of ideal value.Therefore → “1/2 LSB of its final value.”

Verification / Alternative check:
Review ADC/DAC datasheets: settling time is commonly specified to 0.5 LSB, occasionally with other bands for special applications.

Why Other Options Are Wrong:

• 1/8, 1/4, 1 LSB: Not the prevailing standard for general-purpose DAC settling time specs.

Common Pitfalls:
Confusing settling time with rise time or step response 10–90% timing; settling includes final small-signal damping.

Final Answer:
1/2 LSB