Mismatch Implications in Current-Mode Instrumentation Amplifiers
In the different CMIA topologies reported in previous chapters the final value of CMRR is determined by the matching between the used active elements. However, due to the stochastic nature of fabrication processes, the used active elements intended to be matched show different performances. In fact, high CMRR demands both a good circuit topology and a well matching between devices. Therefore, the designer should have good knowledge on both circuit design and mismatches. Owing to the critical role of mismatches in the performance of CMIAs, this chapter reports a brief study on the effect of mismatches in CMIA design. In the first section, a short analysis on the mismatch in CMOS technology is given. Then, the effect of mismatches in different structures of CMIAs is discussed. Later, some effective techniques helpful in reducing mismatches are reviewed. In the last section, a current input CMIA topology with robust performance against mismatches is shown.
- 2.Agarwal K., Nassif S., Liu F., Hayes J., Nowka K. (2007) Rapid characterization of threshold voltage fluctuation in MOS devices. IEEE International Conference on Microelectronic Test Structures, Tokyo, 2007.Google Scholar
- 8.Pandey N., Nanand D., Venkatesh Kumar V., Kumar Ahalawat V., Malhotra C. (2016) Realization of OFCC based transimpedance mode instrumentation amplifier. Theoretical and Applied Electrical Engineering, 14:162–167.Google Scholar
- 9.Pandey R., Pandey N., Paul S. K. (2013) Electronically tunable transimpedance instrumentation amplifier based on OTRA. Journal of Engineering, 10:, Article ID 648540, 5 pages.Google Scholar
- 11.Cini U. (2014) A low-offset high CMRR current-mode instrumentation amplifier using differential difference current conveyor. 1st IEEE International Conference on Electronics, Circuits and Systems (ICECS), Marseille, 2014.Google Scholar
- 13.Laker K. R., Sansen W. M. C. (1994) Design of analog integrated circuits and systems. Spinger, 1994.Google Scholar
- 14.Douglas E. L., Lovely D. F. , Luke D. M. (2004) A low-voltage current-mode instrumentation amplifier designed in a 0.18-micron CMOS technology.Canadian Conference on Electrical and Computer Engineering 2004 (IEEE Cat. No.04CH37513), 2004.Google Scholar