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Adoption of integrated MOS based pseudo-resistor (PR) structures instead of using off-chip passive poly resistors for analog circuits in complementary metal oxide semiconductor technology (CMOS) is an area-efficient way for realizing larger time constants. However, issue of common-mode voltage shifting and excess dependency on the process and temperature variations introduce nonlinearity in such structures. So there is dire need to not only closely look for the origin of the problem with the help of a thorough mathematical analysis but also suggest the most suitable PR structure for the purpose catering broadly to biomedical analog circuit applications.

In this work, incremental resistance (IR) expressions and IR range for balanced PR (BPR) structures operating in the subthreshold region have been closely analyzed for broader range of process-voltage-temperature variations. All the post-layout simulations have been obtained using BSIM3V3 device models in 0.18 µm standard CMOS process.

The obtained results show that the pertinent problem of common-mode voltage shifting in such PR structures is completely resolved in scaled gate linearization and bulk-driven quasi-floating gate (BDQFG) BPR structures. Among all BPR structures, BDQFG BPR remarkably shows constant IR value of 1 TΩ over −1 V to 1 V voltage swing for wider process and temperature variations.

Various balanced PR design techniques reported in this work will help the research community in implementing larger time constants for analog-mixed signal circuits.

The PR design techniques presented in the present piece of work is expected to be used in developing tunable and accurate biomedical prosthetics.

The BPR structures thoroughly analyzed and reported in this work may be useful in the design of analog circuits specifically for applications such as neural signal recording, cardiac electrical impedance tomography and other low-frequency biomedical applications.

The purpose of chopper amplifier is to provide the wideband frequency to support biomedical signals.

This paper proposes a chopper-stabilized amplifier with a cascoded operational transconductance amplifier. The high impedance loop is established using an MOS pseudo resistor and with a tunable MOS capacitor.

The total power consumption is 451 nW with a supplied voltage of 800 mV. The Gain and common mode rejection ratio are 48 dB and 78 dB, respectively.

All kinds of real time data analysis was not carried out, only few test samples related to EEG signals are validated because the real time chip was not manufactured due to funding issues.

The proposed work was validated with Monte-Carlo simulations. There is no external funding for the proposed work. So there is no fabrication for the design. But post simulations are performed.

The high impedance loop is established using an MOS pseudo resistor and with a tunable MOS capacitor. To the best of the author’s knowledge, this concept is completely novel and there are no publications on this work. All the modules designed for chopper amplifier are new concepts.

This paper is a case study of the ideology, strategies and process of the Common Knowledge: Pittsburgh project in its attempt at school reform in an urban school district. The paper reflects on the project’s activities, looks at its efforts from the literature of school reform, and uses its experience to develop a conceptual framework for discussing such reform efforts. The conceptual framework is based on Chaos Theory (Gleick, 1987). The objectives of this paper are to apply Chaos Theory, as developed in mathematics and science to educational organizations and present a conceptual model for school reform consistent with this theory.

This paper aims to present the estimation of the output voltage of metal oxide semiconductor field effect transistor (MOSFET) using the extended Kalman filter (EKF) method.

The method uses EKF for MOSFET output voltage estimation. To implement the EKF method, the state space model has been obtained using Kirchhoff’s current law and Enz-Krummenacher-Vittoz model of the MOSFET circuit.

The proposed method can be used for any mode of MOSFET operation besides near the quiescent point region. The nonlinearity that occurs in the saturation region of MOSFET can also be considered in the proposed method. The proposed method can also be used for a large input signal. Though Kalman filter can be used for the small amplitude input signal, it results in inaccurate estimation due to the linearization of the nonlinear system.

The method is able to track the parameters when they are slowly changing with time.

The proposed method presents maximal precision of simulation as the maximal precision of simulation requires modeling of the circuit in terms of device parameters and circuit elements.