A Configurable Interface for Analog Sensor Outputs

Authors : Baran DEMİRER, Faik BAŞKAYA

Pages : 474-487

Doi:10.16984/saufenbilder.947632

View : 27 | Download : 13

Publication Date : 2022-06-30

Article Type : Research Paper

Abstract :Reading out analog sensor outputs can be a challenging task at low frequencies because of the low frequency noise. To obtain a sensor signal clearly, special interface circuits are required. By using such circuits, analog signals are cleaned from offset, drift and 1/f noise. Besides, if the interface circuitry is configurable, it can be possible to interface to inputs at different frequency ranges. At the interface block, analog sensor output signal is moved to a frequency band where low frequency noise effects are not dominant by using chopping modulation technique. The frequency-shifted signal is then filtered using various filter types. To remove the low frequency noise before moving the signal back to the original band, Gm-C filter is used. The entire topology can be configured by a 5-bit digital to analog converter insert ignore into journalissuearticles values(DAC); called Biasing DAC insert ignore into journalissuearticles values(BDAC);. This allows us to digitally change the biasing current of operational transconductance amplifiers insert ignore into journalissuearticles values(OTA);, so that OTA based amplifiers and filters can operate at different frequency ranges. As conclusion, a configurable analog sensor interface has been designed. The design and layouts have been realized and simulated in Cadence Virtuoso using UMC 130nm CMOS technology.
Keywords : Sensor, Sensor Interfaces, analog