CMOS oversampling ΔΣ magnetic-to-digital converters

Author

Kuo, Chien-Hung ; Chen, Shr-Lung ; Ho, Lee-An ; Liu, Shen-Iuan

Author_Institution

Dept. of Electr. Eng., Nat. Taiwan Univ., Taipei, Taiwan

Volume

36

Issue

10

fYear

2001

fDate

10/1/2001 12:00:00 AM

Firstpage

1582

Lastpage

1586

Abstract

In this paper, two CMOS oversampling delta-sigma (ΔΣ) magnetic-to-digital converters (MDCs) are proposed. The first MDC consists of the magnetic operational amplifier (MOP) and a first-order switched-capacitor (SC) ΔΣ modulator. The second one directly uses the MOP to realize a first-order SC ΔΣ modulator. They can convert the external magnetic field into digital form. Both circuits were fabricated in a 0.5-μm CMOS double-poly double-metal (DPDM) process and operated at a 5-V supply voltage and the nominal sampling rate of 2.5 MHz. The dynamic ranges of these converters are at least ±100 mT. The gain errors within ±100 mT are less than 3% and the minimum detectable magnetic field can reach as small as 1 mT. The resolutions are 100 μT for both of the two MDCs. The measured sensitivities are 1.327 mv/mT and 0.45 mv/mT for the first and the second MDC, respectively

Keywords

CMOS integrated circuits; delta-sigma modulation; magnetic amplifiers; magnetic sensors; operational amplifiers; switched capacitor networks; 0.5 micron; 2.5 MHz; 5 V; CMOS oversampling delta-sigma magnetic-to-digital converter; double-poly double-metal process; magnetic operational amplifier; magnetic sensor; switched-capacitor modulator; CMOS process; Circuits; Delta modulation; Magnetic field measurement; Magnetic fields; Magnetic modulators; Magnetic switching; Operational amplifiers; Sampling methods; Voltage;

fLanguage

English

Journal_Title

Solid-State Circuits, IEEE Journal of

Publisher

ieee

ISSN

0018-9200

Type

jour

DOI

10.1109/4.953488

Filename

953488