Название: Current-Mode Instrumentation Amplifiers
Автор: Leila Safari, Giuseppe Ferri, Shahram Minaei, Vincenzo Stornelli
Издательство: Springer
Серия: Analog Circuits and Signal Processing
ISBN: 3030013421
Год: 2019
Страниц: 200
Язык: английский
Формат: pdf (true), epub
Размер: 18.3 MB

This book describes a new way to design and utilize Instrumentation Amplifiers (IAs) by taking advantages of the current-mode (CM) approach. For the first time, all different topologies of CMIAs are discussed and compared, providing a single-source reference for instrumentation and measurement experts who want to choose a topology for a specific application. The authors also explain major challenges in designing CMIAs, so the book can be useful for anyone studying instrumentation amplifiers, and even other analog circuits. Coverage also includes various CM signal processing techniques employed in CMIAs, and applications of the CMIAs in biomedical and data acquisition are demonstrated.

Instrumentation amplifiers (IAs) are among the oldest and most widely used circuits that ensure a weak differential signal amplification in the presence of strong noises and common-mode signals. In the past, IAs were implemented using Op-Amps and resistors. Their major problem is the strict matching requirement between resistors to achieve a high common-mode rejection ratio (CMRR). Another limitation associated with Op-Amp-based IAs is their gain-dependent bandwidth. These weaknesses along with the rapid downscale of CMOS technology with reduced allowed supply voltages have made the Op-Amp-based IAs less attractive. Fortunately, after the emergence of current-mode signal processing, designers took the advantages of current-mode technique to mitigate the problems associated with Op-Amp-based IAs. Compared to conventional voltage-mode signal processing, the new technique showed interesting features such as wide frequency performance, simpler circuitry, low-voltage operation. This new generation of IAs based on current-mode signal processing is known as current-mode instrumentation amplifiers (CMIAs). Although signal processing is performed in current domain, the input and output signals in CMIAs can be current or voltage signals.