High-power CMOS current driver with accurate transconductance for electrical impedance tomography

Constantinou, Loucas, Triantis, Iasonas F., Bayford, Richard ORCID logoORCID: https://orcid.org/0000-0001-8863-6385 and Demosthenous, Andreas (2014) High-power CMOS current driver with accurate transconductance for electrical impedance tomography. IEEE Transactions on Biomedical Circuits and Systems, 8 (4) . pp. 575-583. ISSN 1932-4545 [Article] (doi:10.1109/TBCAS.2013.2285481)


Current drivers are fundamental circuits in bioimpedance measurements including electrical impedance tomography (EIT). In the case of EIT, the current driver is required to have a large output impedance to guarantee high current accuracy over a wide range of load impedance values. This paper presents an integrated current driver which meets these requirements and is capable of delivering large sinusoidal currents to the load. The current driver employs a differential architecture and negative feedback, the latter allowing the output current to be accurately set by the ratio of the input voltage to a resistor value. The circuit was fabricated in a 0.6-μm high-voltage CMOS process technology and its core occupies a silicon area of 0.64 mm 2 . It operates from a ± 9 V power supply and can deliver output currents up to 5 mA p-p. The accuracy of the maximum output current is within 0.41% up to 500 kHz, reducing to 0.47% at 1 MHz with a total harmonic distortion of 0.69%. The output impedance is 665 kΩ at 100 kHz and 372 kΩ at 500 kHz.

Item Type: Article
Research Areas: A. > School of Science and Technology > Natural Sciences > Biophysics and Bioengineering group
Item ID: 15514
Depositing User: Richard Bayford
Date Deposited: 28 Apr 2015 15:18
Last Modified: 30 Jan 2023 14:21
URI: https://eprints.mdx.ac.uk/id/eprint/15514

Actions (login required)

View Item View Item


Activity Overview
6 month trend
6 month trend

Additional statistics are available via IRStats2.