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By Eamon Nash.

Byline Eamon Nash, Analog Devices. Equations (1)–(2): CMRR as the differential-to-common gain ratio and resulting common-mode output error.

Primary publisher page explicitly credits Eamon Nash and is dated1July1998. Introduction describes differential amplification of bridge/thermocouple signals; equations1–2 give finite common-mode gain and rejection. Common Mode Voltage Range distinguishes input operating limits from rejection performance. The older PDF URL redirects to this publisher page.

Eamon Nash is an applications engineer whose technical writing connects amplifier models with measurements of real circuits. His A Practical Review of Common Mode and Instrumentation Amplifiers by Eamon Nash explains how finite common-mode rejection ratio converts a shared input disturbance into output error, even when the desired signal is differential.^[ref]

His later RF-modeling article compares simulated and measured amplifier behavior. Small-signal scattering parameters describe linear gain and matching, but additional data are needed for noise and nonlinear compression. One demonstrated limitation is especially instructive: a model can reproduce amplitude compression while missing signal-dependent phase distortion because its input data contain only small-signal phase. That makes the disagreement scientifically useful evidence about what information the model lacks.^[ref]