Analysis of Clock Jitter in Continuous-Time Sigma–Delta Modulators

One of the factors limiting the performance of continuous-time sigma-delta modulators (CTSDMs) is clock jitter. This jitter can be classified as synchronous and accumulated/long-term jitter. A clock that is derived from a phase-lock loop contains both types of jitter. In this paper, we present a framework that can be used to obtain the output spectrum in the presence of jitter, either synchronous or accumulated or a combination of both. First, a general expression for the output power spectral density (PSD) of the CTSDM in the presence of clock jitter is derived. Based on this, analytical expressions for the output PSD are obtained for particular cases of synchronous and long-term jitter. These are validated against behavioral simulations.

[1]  Arthur H. M. van Roermund,et al.  A general analysis on the timing jitter in D/A converters , 2002, 2002 IEEE International Symposium on Circuits and Systems. Proceedings (Cat. No.02CH37353).

[2]  O. Oliaei State-space analysis of clock jitter in continuous-time oversampling data converters , 2003 .

[3]  Amit Mehrotra,et al.  Noise analysis of phase-locked loops , 2000, IEEE/ACM International Conference on Computer Aided Design. ICCAD - 2000. IEEE/ACM Digest of Technical Papers (Cat. No.00CH37140).

[4]  Chao-Cheng Lee,et al.  An Analytical Approach for Quantifying Clock Jitter Effects in Continuous-Time Sigma–Delta Modulators , 2006, IEEE Transactions on Circuits and Systems I: Regular Papers.

[5]  N. Jeremy Usdin,et al.  Discrete Simulation of Colored Noise and Stochastic Processes and llf" Power Law Noise Generation , 1995 .

[6]  V.,et al.  On the Problem of Time Jitter in Sampling * , 1998 .

[7]  W. Snelgrove,et al.  Clock jitter and quantizer metastability in continuous-time delta-sigma modulators , 1999 .

[8]  K. F. Riley,et al.  Mathematical Methods for Physics and Engineering , 1998 .

[9]  N. Kasdin Discrete simulation of colored noise and stochastic processes and 1/fα power law noise generation , 1995, Proc. IEEE.

[10]  Carmen J. Palermo,et al.  System performance in the presence of stochastic delays , 1962, IRE Trans. Inf. Theory.

[11]  H. Tao,et al.  Analysis of timing jitter in bandpass sigma-delta modulators , 1999 .

[12]  V. Vasudevan,et al.  Simulation of the effects of timing jitter in track-and-hold and sample-and-hold circuits , 2005, Proceedings. 42nd Design Automation Conference, 2005..

[13]  K. S. Kundert Predicting the Phase Noise of PLL-Based Frequency Synthesizers , 2001 .