Abstract
A novel first-order CMOS log-domain filter is presented. The internal voltage swing compression due to its instantaneous voltage companding nature, together with the use of Floating-Gate MOS transistors and its class AB differential topology, allows operation with a single 1 V supply while maintaining at the same time a large input range. Moreover, operation in weak inversion leads to very low power consumption. The filter can be tuned in more than one decade through its bias currents. Simulation and measurement results of an experimental prototype fabricated in a 0.8 μm CMOS technology demonstrate on silicon the feasibility of the proposed technique, which can be readily extended to higher-order filters.
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López-MartÍn, A.J., Fernández, R., de la Cruz Blas, C.A. et al. A 1 V Micropower FGMOS Class AB Log-Domain Filter. Analog Integrated Circuits and Signal Processing 41, 137–145 (2004). https://doi.org/10.1023/B:ALOG.0000041631.38645.c7
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DOI: https://doi.org/10.1023/B:ALOG.0000041631.38645.c7