Fully integrated programmable Howland current source for sensors excitation

Author

Pelicia, Marcos Mauricio ; Filho, Carlos A dos Reis

Author_Institution

Sch. of Electr. & Comput. Eng., State Univ. of Campinas, Sao Paulo, Brazil

fYear

2002

fDate

6/24/1905 12:00:00 AM

Abstract

In this paper a fully integrated implementation of the classical Howland current source is presented as a compact solution for exciting resistive and piezoresistive sensors. This circuit, which is part of a programmable signal conditioning microsystem, described elsewhere, is treated as a module that is capable of providing a voltage-adjustable current whose full-scale is 10 mA. Experimental results from samples manufactured in 0.8 μm CMOS have shown that the circuit features a full-scale nonlinearity of 0.042% powered by a supply voltage of 5 V. The measured frequency response using a 50 Ω resistive load rolls off at 228 kHz, which is in excess of the predicted applications.

Keywords

CMOS analogue integrated circuits; active networks; constant current sources; electric sensing devices; frequency response; modules; piezoresistive devices; programmable circuits; 0.8 micron; 10 mA; 228 kHz; 5 V; 50 ohm; CMOS fabrication; CMOS fully integrated programmable Howland current sources; frequency response roll off; full-scale nonlinearity; modules; piezoresistive sensor excitation; power supply voltage; programmable signal conditioning microsystems; resistive load; resistive sensor excitation; voltage-adjustable current sources; CMOS technology; Circuits; Frequency measurement; Frequency response; Manufacturing; Piezoresistance; Power supplies; Resistors; Thermal sensors; Voltage control;

fLanguage

English

Publisher

ieee

Conference_Titel

Devices, Circuits and Systems, 2002. Proceedings of the Fourth IEEE International Caracas Conference on

Print_ISBN

0-7803-7380-4

Type

conf

DOI

10.1109/ICCDCS.2002.1004016

Filename

1004016