Title :
A 0.7-V MOSFET-only switched-opamp ΣΔ modulator in standard digital CMOS technology
Author :
Sauerbrey, Jens ; Tille, Thomas ; Schmitt-Landsiedel, Doris ; Thewes, Roland
Author_Institution :
Corporate Res., Infineon Technol. AG, Munich, Germany
fDate :
12/1/2002 12:00:00 AM
Abstract :
A 0.7-V MOSFET-only ΣΔ modulator for voice band applications is presented. The second-order modulator is realized using a switched-opamp technique. All capacitors are realized using compensated MOS devices operated in the depletion region. A combination of parallel and series compensated depletion-mode MOSCAPs is used to obtain high area efficiency. The circuit is fabricated in a 0.18-μm CMOS process. The only components used are standard n-MOS and p-MOS transistors with threshold voltages of approximately 400 mV. All transistors are operated within the supply voltage window of 0.7 V; voltage boosting techniques are not used. The active area is 0.082 mm2. The modulator achieves 67-dB signal-to-noise-and-distortion ratio, 70-dB signal-to-noise ratio, and 75-dB dynamic range at 8-kHz signal bandwidth and consumes 80 μW of power.
Keywords :
CMOS integrated circuits; circuit optimisation; compensation; integrated circuit design; integrated circuit reliability; low-power electronics; sigma-delta modulation; switched networks; 0.18 micron; 0.7 V; 400 mV; 8 kHz; 80 muW; MOSCAPs; MOSFET-only circuit; active area; area efficiency; compensated MOS devices; depletion region; digital CMOS technology; second-order modulator; signal-to-noise ratio; signal-to-noise-and-distortion ratio; supply voltage window; switched-opamp ΣΔ modulator; switched-opamp technique; threshold voltages; voice band applications; voltage boosting techniques; Boosting; CMOS process; CMOS technology; Circuits; Digital modulation; MOS capacitors; MOS devices; MOSFETs; Signal to noise ratio; Threshold voltage;
Journal_Title :
Solid-State Circuits, IEEE Journal of
DOI :
10.1109/JSSC.2002.804330
