Stable Delta-Sigma Modulator with Signal Dependent Forward Path Gain for Industrial Applications
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 33092
Stable Delta-Sigma Modulator with Signal Dependent Forward Path Gain for Industrial Applications

Authors: K. Diwakar, K. Aanandha Saravanan, C. Senthilpari

Abstract:

Higher order ΔΣ Modulator (DSM) is basically an unstable system. The approximate conditions for stability cannot be used for the design of a DSM for industrial applications where risk is involved. The existing second order, single stage, single bit, unity feedback gain , discrete DSM cannot be used for the normalized full range (-1 to +1) of an input signal since the DSM becomes unstable when the input signal is above ±0.55. The stability is also not guaranteed for input signals of amplitude less than ±0.55. In the present paper, the above mentioned second order DSM is modified with input signal dependent forward path gain. The proposed DSM is suitable for industrial applications where one needs the digital representation of the analog input signal, during each sampling period. The proposed DSM can operate almost for the full range of input signals (-0.95 to +0.95) without causing instability, assuming that the second integrator output should not exceed the circuit supply voltage, ±15 Volts.

Keywords: DSM, stability, SNR, state variables.

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1098140

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1587

References:


[1] Richard Schreier, Gabor C. Temes, Understanding Delta-Sigma DataConverters, (IEEE Press, 2005).
[2] S.R. Norsworthy, R.Schreier and G.C. Temes, Eds., Delta-Sigma Data Converters, (IEEE Press, 1997).
[3] George I Bourdopoulos, Delta-Sigma Modulators Modeling, Design and Applications, (Imperial College Press, 2003).
[4] S. Hein and A. Zahor, “On the stability of interpolative sigma delta modulators,” IEEE Transcations on Signal Processing, Vol.41, No.7, July (1993), pp. 2322-2348.
[5] Bourdopoulos G.I. “Adaptive order reduction scheme for high-order single-bit ΔΣModulators” IEEE Transactions on Circuits and Systems, Vol. 51, No. 5, pp. 213- 216,2004.
[6] Maghari N., Kwon S., Temes G.C. and Moon U. “Mixed – Order Sturdy MASH Δ-Σ Modulator”IEEE International symposium on Circuits and Systems, pp. 257-260, 2007.
[7] Jiaxin, Wanrong Zhang, Haolin Du, Yanfeng Jiang and YaminZhang ) “New architecture of low voltage Sigma-Delta ADC” IEEE 8th International Conference on ASIC, pp. 203-206, 2009.
[8] Yavari M, Shoaei O and Rodriguez-Vazquez A “Double-sampling single-loop Sigma-Delta Modulator topologies for broad- band applications” IEEE Transactions on Circuits and Systems II, Vol.53, No.4, pp. 314-318,2007.
[9] Maghari N., Temes G.C. and Moon U. “Single loop ΔΣ modulator with extended dynamic range” Electronics letters, Vol.44, No.25, pp. 1452- 1453,2008.
[10] Yongsheng Wang ; Yuanhong Li ; Mingyan Yu “A 16 bit low voltage low power Delta Sigma modulator”, Conference on Electronic and Mechanical Engineering and Information Technology (EMEIT), 2011 Vol. 6, Pages: 3178 – 3181.
[11] Mohammadi, R. , Shamsi, H. , Abedinkhan, M., “On the designof a 2-2- 0 MASH delta-sigma-pipeline modulator”, IEEE International Conference on Electronics, Circuits and Systems (ICECS), 2012 , Page(s): 348 - 351 .
[12] Athar S., Siddiqi M.A. , Masud S. “Design and FPGA Implementation of a 2nd Order Adaptive delta signma modulator with One Bit Quantization”, 2010 , Page(s): 388 – 393.
[13] Youngjae Jung, HyungdongRoh, “An Input-Feedforward Multibit Adder-Less Modulator for Ultrasound Imaging Systems”, IEEE Transactions on Instrumentation and Measurement, Vol.62, No.8, August 2013, Pages 2215-2227.