Principles of Instrumentation Amplifiers
This chapter is dedicated to the general principles of the Instrumentation Amplifier, a particular type of differential amplifier hereafter called IA. Its basic applications are reviewed. The definitions of Common-Mode Rejection Ratio (CMRR) as the most important property of IAs are discussed. It is shown that the CMRR definition is different in single output and fully differential circuits. The general formula for derivation of CMRR in cascaded stages is given. Then, the well-known classical 3-Op-Amp IA is studied. Its important parameters, limitations and disadvantageous are discussed. The chapter includes also a brief introduction and the classification of IAs developed with current-mode techniques here after called Current-Mode Instrumentation Amplifier (CMIA).
- 1.Kitchin C., Counts L. (2006), A Designer’s guide to instrumentation amplifiers, 3rd Edition, Analog Device, USA.Google Scholar
- 7.Wilson B., Lidgey F. J., Toumazou C. (1988), Current mode signal processing circuits, IEEE International Symposium on Circuits and Systems, Espoo, Finland, 3:2665–2668.Google Scholar
- 8.Arbel A. F. (1991), Current-mode signal processing, 17th Convention of Electrical and Electronics Engineers in Israel, Tel Aviv, 1991.Google Scholar
- 9.Toumazou C., Lidgey F. J., Haigh D. (1992), Analogue IC design: the current-mode approach, IET.Google Scholar
- 12.Cini U. (2014), A low-offset high CMRR current-mode instrumentation amplifier using differential difference current conveyor, IEEE International Conference on Electronics, Circuits and Systems (ICECS), 2014.Google Scholar
- 14.Yang T. Y., Liu K. Y., Wang H. Y. (2011), Novel high-CMRR DVCC-based instrumentation amplifier, 2nd International Conference on Engineering and Industries (ICEI), 2011.Google Scholar