Title :
Design of continuous-time ΣΔ modulators with sine-shaped feedback DACs
Author :
Latiri, Anis ; Aboushady, Hassan ; Beilleau, Nicolas
Author_Institution :
LIP6/ASIM Lab., Univ. Paris VI, France
Abstract :
This work presents a general method to design continuous-time ΣΔ modulators with sine-shaped feedback DACs. A discrete time to continuous time transformation technique is used to compute the continuous-time loop filter coefficients, taking into account the sinusoidal feedback. Examples of high order lowpass and bandpass continuous-time ΣΔ modulators are given as an illustration for the proposed design method. A transistor level sine-shaped feedback DAC is also proposed and compared to a recent circuit design. Finally, the sensitivity of these circuits to clock jitter is studied and compared to the traditional rectangular feedback pulse.
Keywords :
band-pass filters; circuit feedback; continuous time filters; low-pass filters; network synthesis; sensitivity; sigma-delta modulation; timing jitter; circuit clock jitter sensitivity; circuit design; continuous-time ΣΔ modulators; continuous-time loop filter coefficients; design; discrete time to continuous time transformation technique; high order bandpass continuous-time ΣΔ modulators; high order lowpass continuous-time ΣΔ modulators; rectangular feedback pulse; sine-shaped feedback DAC; sinusoidal feedback; transistor level sine-shaped feedback DAC; Band pass filters; Circuit synthesis; Clocks; Delay; Design methodology; Feedback loop; Jitter; Laboratories; Sampling methods; Transfer functions;
Conference_Titel :
Circuits and Systems, 2005. ISCAS 2005. IEEE International Symposium on
Print_ISBN :
0-7803-8834-8
DOI :
10.1109/ISCAS.2005.1465426
