CMOS multichannel sensor interface circuit using oversampled sigma-delta A-to-D conversion

Lindell, M.; Tenhunen, Hannu

doi:10.1109/cmpeur.1989.93419

Cited by 3 publications

(1 citation statement)

References 6 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Single-bit RD modulators have become very popular for A/D conversion in sensor interfaces [23]. Their main advantage over other converters is that no highprecision elements dividing the reference voltage are needed.…”

Section: Single-bit Rd-modulation Techniques For Sensor Interfacesmentioning

confidence: 99%

CMOS Single‐chip Gas Detection Systems: Part II

2003

View full text Add to dashboard Cite

Sensor arrays based on industrial CMOS-technology combined with post-CMOS micromachining (CMOS MEMS) are a promising approach to low-cost sensors. In the first part of this article [1], the state of research on CMOS-based gas sensor systems was reviewed, and a platform technology for monolithic integration of three different transducers on a single chip was described. In this second part, the transduction principles of three polymer-based gas sensors are detailed and the read-out circuitry is portrayed. The first transducer is a micromachined resonant cantilever. The absorption of analyte in the chemically sensitive polymer causes shifts in resonance frequency as a consequence of changes in the oscillating mass. The cantilever acts as the frequency-determining element in an oscillator circuit, and the resulting frequency change is read out by an on-chip counter. The second transducer is a planar capacitor with polymer-coated interdigitated electrodes. This transducer monitors changes in the dielectric constant upon absorption of the analyte into the polymer matrix. The sensor response is read out as a differential signal between the coated sensing capacitor and a passivated reference capacitor, both of which are incorporated into the input stage of a switched capacitor second-order RD-modulator. The third transducer is a thermoelectric calorimeter, which detects enthalpy changes upon ab-/desorption of analyte molecules into a polymer film located on a thermally insulated membrane. The enthalpy changes in the polymer film cause transient temperature variations, which are detected via polysilicon/aluminum thermocouples (Seebeck effect). The small signals in the lVrange are first amplified with a low-noise chopper amplifier, then converted to a digital signal using a RD-A/D-converter and finally decimated and filtered with a digital decimation filter.

show abstract

Section: Single-bit Rd-modulation Techniques For Sensor Interfacesmentioning

confidence: 99%

CMOS Single‐chip Gas Detection Systems: Part II

2003

View full text Add to dashboard Cite

show abstract

Oversampled A/D and D/A converters for VLSI system integration

Ritoniemi

Eerola

Karema

et al.

Third Annual IEEE Proceedings on ASIC Seminar and Exhibit

View full text Add to dashboard Cite

A low power 6-bit A/D converter achieving 10-bit resolution for MEMS sensor interface using time-interleaved delta modulation

De¹,

Kal

2006

19th International Conference on VLSI Design Held Jointly With 5th International Conference on Embedded Systems Design (VLSID'0

View full text Add to dashboard Cite

This paper describes time-interleaved delta ADC as a digital interface for low frequency MEMS sensor signal. The design is presented as a simple low power solution for A/D conversion in comparison to popular sigma-delta converters. Conventional delta modulator is modified with insertion of an array of comparators and a coder i.e. an up/down counter. Time interleaving is done within the array to operate the sensitive analog part in slower speed while maintaining a higher oversampling ratio of the converter. The up/down counter acts as low-pass filter in the delta modulation loop and by resetting it in proper interval decimationcan also be performed. Simulation of the test structure for the 6-bit ADC in 0.18µm CMOS process shows output SNR of 60dB, with INL and DNLs less than 0.5 LSB. The output SNR is equivalent to 10-bit of resolution. To obtain such resolution with only 6-bit output the total power the design consumes from a single 1.8 V supply is only 2.3mW. The die area of the ADC is only 0.8mm×0.6mm.

show abstract

CMOS multichannel sensor interface circuit using oversampled sigma-delta A-to-D conversion

Cited by 3 publications

References 6 publications

CMOS Single‐chip Gas Detection Systems: Part II

CMOS Single‐chip Gas Detection Systems: Part II

Oversampled A/D and D/A converters for VLSI system integration

A low power 6-bit A/D converter achieving 10-bit resolution for MEMS sensor interface using time-interleaved delta modulation

Contact Info

Product

Resources

About