Susceptibility of CMOS Voltage Comparators to Radio Frequency Interference

This paper deals with the susceptibility to RF interference (RFI) of common CMOS voltage comparators. Approximate nonlinear analysis and time-domain computer simulations are carried out to highlight the causes of the false commutations induced by the disturbances superimposed onto the nominal input signals. Through these investigations, it is shown that the response of voltage comparators to RFI depends on the comparator initial state. This effect is also confirmed by the results of measurements carried out on a CMOS voltage comparator embedded in a test chip. Based on this, a new voltage comparator that avoids false commutations induced by high-frequency disturbances is proposed.

[1]  A Richelli.  CMOS OpAmp Resisting to Large Electromagnetic Interferences , 2010, IEEE Transactions on Electromagnetic Compatibility.

[2]  Behzad Razavi,et al.  Principles of Data Conversion System Design , 1994 .

[3]  Phillip E Allen,et al.  CMOS Analog Circuit Design , 1987 .

[4]  Piet Wambacq,et al.  Distortion analysis of analog integrated circuits , 1998 .

[5]  R. E. Richardson.  Quiescent operating point shift in bipolar transistors with AC excitation , 1979 .

[6]  Wouter A. Serdijn,et al.  Systematic Design of a Transimpedance Amplifier With Specified Electromagnetic Out-of-Band Interference Behavior , 2010, IEEE Transactions on Circuits and Systems I: Regular Papers.

[7]  Willy Sansen,et al.  Distortion in elementary transistor circuits , 1999 .

[8]  F. Fiori.  Design of an Operational Amplifier Input Stage Immune to EMI , 2007, IEEE Transactions on Electromagnetic Compatibility.

[9]  Pamela Abshire,et al.  A 1.2-GHz comparator with adaptable offset in 0.35-μm CMOS , 2008, IEEE Transactions on Circuits and Systems I: Regular Papers.

[10]  Gabor C. Temes,et al.  Circuit techniques for reducing the effects of op-amp imperfections: autozeroing, correlated double sampling, and chopper stabilization , 1996, Proc. IEEE.

[11]  Peter R. Kinget,et al.  High-Frequency Distortion Analysis of Analog Integrated Circuits , 1999 .

[12]  Horst Zimmermann,et al.  A Comparator With Reduced Delay Time in 65-nm CMOS for Supply Voltages Down to 0.65 V , 2009, IEEE Transactions on Circuits and Systems II: Express Briefs.