An instrumentation amplifier used for precision sensing is specifically designed to exhibit a very high value of which performance metric, enabling accurate extraction of small differential signals in the presence of large common-mode voltages?

Introduction / Context:
Instrumentation amplifiers (in-amps) are the front-end choice in medical, industrial, and measurement systems precisely because they can reject large common-mode voltages while amplifying tiny differential signals. The figure of merit that quantifies this capability is the common-mode rejection ratio (CMRR).

Given Data / Assumptions:

• Differential input signals can be microvolts to millivolts.
• Common-mode voltages may be tens of volts or more.
• Balanced resistor networks and topology are optimized for high CMRR.

Concept / Approach:
CMRR is the ratio of differential gain to common-mode gain. A high CMRR means the amplifier strongly suppresses any voltage common to both inputs (such as interference or ground shifts) while accurately amplifying the difference. Three-op-amp in-amps use matched resistor networks to achieve orders of magnitude better CMRR than simple differential amplifiers built from unmatched parts.

Step-by-Step Solution:
Recognize the desired attribute: reject common-mode, pass differential.Identify the metric: CMRR = Ad / Acm (often specified in dB).Relate to design: precision resistor matching and topology maximize CMRR.Conclude: an in-amp is characterized by very high CMRR.

Verification / Alternative check:
Datasheets list CMRR values (often 90–120 dB or higher), directly demonstrating the in-amp’s strength versus general-purpose op-amp stages.

Why Other Options Are Wrong:
Output impedance is deliberately low, not high, for driving loads.

Power gain and supply voltage are application-dependent and not the defining features.

Slew rate is important for speed but does not address common-mode error rejection.

Common Pitfalls:
Neglecting resistor tolerance and layout symmetry can degrade practical CMRR dramatically even when the IC specification is high.

Final Answer:
CMRR