Miscellaneous active electrical nonlinear devices – circuits – and – Signal converting – shaping – or generating – Amplitude control
Reexamination Certificate
2008-03-25
2008-03-25
Tra, Quan (Department: 2816)
Miscellaneous active electrical nonlinear devices, circuits, and
Signal converting, shaping, or generating
Amplitude control
C375S345000, C455S223000
Reexamination Certificate
active
11074484
ABSTRACT:
An auto-zero circuit is disclosed. The auto-zero circuit includes a first set of circuits for implementing a first auto-zero phase and a second set of circuits for implementing a second auto-zero phase. The first set of circuits includes a first differential amplifier and a first feedback path coupled between an output of the first differential amplifier and an input of the first differential amplifier. The second set of circuits includes a second differential amplifier and a second feedback path coupled between an output of the second differential amplifier and an input of the first differential amplifier, where the second feedback path includes an attenuation capacitor for reducing charge injection error and noise error of the auto-zero circuit and a holding capacitor for holding a voltage to be used to correct charge injection error introduced by the first feedback path.
REFERENCES:
patent: 4453258 (1984-06-01), Richardson
patent: 5027116 (1991-06-01), Armstrong et al.
Graf, Rudolf, Modern dictionary of electronics, 7. ed., rev. and updated. Boston [u.a.]. Newnes. 1999. 869 S.. pp. (109 and 543).
Bakker, A. et al. (Dec. 2000). “A CMOS Nested-Chopper Instrumentation Amplifier with 100-nV Offset,”IEEE Journal of Solid-State Circuits35(12):1877-1883.
Begueret, J.-B. et al. (Mar. 1997). “Converters Dedicated to Long-Term Monitoring of Strain Gauge Transducers,”IEEE Journal of Solid-State Circuits32(3):349-356.
Coln, M.C.W. (Dec. 1981). “Chopper Stabilization of MOS Operational Amplifiers Using Feed-Forward Techniques,”IEEE Journal of Solid-State CircuitsSC-16(6):745-748.
Enz, C.C. et al. (Jun. 1987). “A CMOS Chopper Amplifier,”IEEE Journal of Solid-State CircuitsSC-22(3):335-342.
Finvers, I.G. et al. (Feb. 1995). “ A High Temperature Precision Amplifier,”IEEE Journal of Solid-State Circuits30(2):120-128.
Fotouhi, B. (Jul. 1994). “Optimization of Chopper Amplifiers for Speed and Gain,”IEEE Journal of Solid-State Circuits29(7):823-828.
Menolfi, C. et al. (Mar. 1999). “A Fully Integrated, Untrimmed CMOS Instrumentation Amplifier with Submicrovolt Offset,”IEEE Journal of Solid-State Circuits34(3):415-420.
Brown Jim
Naviasky Eric
Almo Khareem
Cadence Design Systems Inc.
Morrison & Foerster / LLP
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