Title :
A 106-dB SNR hybrid oversampling analog-to-digital converter for digital audio
Author :
Nguyen, Khiem ; Adams, Robert ; Sweetland, Karl ; Chen, Huaijin
Author_Institution :
Analog Devices Inc., Wilmington, MA, USA
Abstract :
An audio ΣΔ analog-to-digital converter (ADC) with the loop filter implemented by continuous-time (CT) and discrete-time (DT) circuits is presented. A tuning circuit is used to compensate for changes in the RC product due to process skew, power supply, temperature and sampling rate variation. To eliminate errors caused by inter-symbol interference (ISI) in the CT feedback DAC, a return-to-zero (RTZ) switching scheme is applied on the error current of the CT integrator. The converter is fabricated in a 0.35-μm CMOS process, and achieves 106-dB dynamic range, -99-dB THD+N.
Keywords :
CMOS integrated circuits; RC circuits; continuous time filters; discrete time filters; sigma-delta modulation; signal sampling; 0.35 micron; CMOS process; analog-to-digital converter; continuous time integrator; continuous-time circuit; digital audio; discrete-time circuit; inter-symbol interference; loop filter; return-to-zero switching scheme; sampling rate variation; tuning circuit; Analog-digital conversion; CMOS process; Circuit optimization; Feedback; Filters; Interference elimination; Intersymbol interference; Power supplies; Sampling methods; Temperature; Continuous time; oversampling ADC;
Journal_Title :
Solid-State Circuits, IEEE Journal of
DOI :
10.1109/JSSC.2005.856284
