Design of a range-segmented CMOS current-mode exponential circuit

Authors

CHIH-JEN CHENG
KUO-JEN LIN
JWU-E CHEN

Abstract

A CMOS current-mode exponential circuit is designed by plugging candidate circuits into a Taylor's approximation circuit to make a multiple-segment circuit. The selection of candidate circuits is dependent on a large linearity range in each segment. The proposed range-segmented circuit is different from all segments constructed only by quadratic circuits or only by linear circuits. The proposed circuit was simulated using UMC 0.18~$\mu$m CMOS technology. The output linearity of the circuit is 56.7~dB for gain error less than 0.5~dB, and the --3~dB bandwidth of the circuit is between 69 and 150~MHz for input range from --63 to 198~$\mu$A.

DOI

10.3906/elk-1811-32

Keywords

Exponential circuit, multiple-segments circuit, current-mode circuit, quadratic circuit

First Page

2475

Last Page

2487

Recommended Citation

CHENG, CHIH-JEN; LIN, KUO-JEN; and CHEN, JWU-E (2019) "Design of a range-segmented CMOS current-mode exponential circuit," Turkish Journal of Electrical Engineering and Computer Sciences: Vol. 27: No. 4, Article 8. https://doi.org/10.3906/elk-1811-32
Available at: https://journals.tubitak.gov.tr/elektrik/vol27/iss4/8