Title :
Ultra low-voltage MOSFET-only switched-Opamp Σ Δ modulators using depletion-mode MOS-capacitors
Author :
Tille, T. ; Sauerbrey, J. ; Thewes, R. ; Schmitt-Landsiedel, Doris
Author_Institution :
Technical University of Munich, Munich, Germany
Abstract :
Four implementations of MOSFET-Only ΣΔ modulators for audio applications are presented using different topologies of depletion-mode MOS-capacitors. The 2nd-order fully-differential modulators are realized in Switched-Opamp technique with DC level shift. Implementation is performed in a standard 0.18µm digital n-well CMOS process without using extra process options to provide linear capacitors. The SNDRs of the different modulators are within the range of 62dB to 67dB whereas SNR of 69dB and a dynamic range of 73dB is obtained, respectively. The modulators are operated at 16kHz signal bandwidth and consume approximately 200µW from a single 0.9V power supply.
Keywords :
Bandwidth; CMOS process; CMOS technology; Circuit topology; Linearity; Low voltage; MOS capacitors; MOSFET circuits; Operational amplifiers; Read only memory;
Conference_Titel :
Solid-State Circuits Conference, 2002. ESSCIRC 2002. Proceedings of the 28th European
Conference_Location :
Florence, Italy
