Sine-shaping of feedback DAC current in continuous-time Σ∆ ADCs is an effective solution to enhance their immunity to clock jitter. In this paper, a simple mixer circuit for producing a sine-shaped output in continuous-time Σ∆ ADCs is introduced. The proposed solution does not need extra clock source or synchronization circuit, as the mixer utilizes the same clock applied to the comparator. It ...

This paper describes the design of a bandgap reference, implemented in 0.50 μm CMOS technology. The circuit generates a reference voltage of 1.2218V. It can operate between 20oC & 70o C. Total variation of reference voltage within the temperature range is 2.6mV which is 0.213% of the reference voltage. This circuit works in a current feedback mode, and it generates its own reference current, re...

In this paper we present an electronic circuit for position or capacitance estimation of MEMS electrostatic actuators based on a switched capacitor technique. The circuit uses a capacitive divider configuration composed by a fixed capacitor and the variable capacitance of the electrostatic actuator for generating a signal that is a function of the input voltage and capacitive ratio. The propose...

In this paper we present an electronic circuit for position or capacitance estimation of MEMS electrostatic actuators based on a switched capacitor technique. The circuit uses a capacitive divider configuration composed by a fixed capacitor and the variable capacitance of the electrostatic actuator for generating a signal that is a function of the input voltage and capacitive ratio. The propose...

This paper provides electronic implementation of electrocardiograph (ECG) circuit by using instrumentation amplifier (IA) as bio-potential amplifier in such a manner which reduces noise, common voltage, DC offset value and RF interference from the existing circuit.Noise and common voltage can be removed from ECG using driven right leg circuit or by using isolator circuit. DC offset can be remov...

A method for assessing and optimizing the feedback level in a transistor-grid oscillator is presented. Based on the approximate large-signal S-parameters of the transistor, an equivalent circuit model for the grid is synthesized for maximum oscillator power. The resulting circuit serves as a convenient benchmark for determining the level of feedback for a given grid. Experimental results are pr...

At present, the control of a dynamic system (the ‘$plant”) is generally done by means of feedback. This paper proposes a n alternative approach that uses adaptive filtering to achieve feedforward control f o r both linear and nonlinear plants. Precision is attained because of the feedback incorporated in the adaptive filtering. Disturbance in the plant can be optimally controlled by a special c...

Time jitter in continuous-time modulators is a known limitation on the maximum achievable signal-to-noise-ratio (SNR). Analysis of time jitter in this type of converter shows that a switched-capacitor (SC) feedback digital-to-analog converter (DAC) reduces the sensitivity to time jitter significantly. In this paper, an and continuous-time fifth-order modulator with 1-bit quantizer and SC feedba...

In this paper, we present a further mathematical study on the report of existence of n-scroll chaotic attractors in a modified Chua’s circuit. A series of results based on mathematical theory are given. First, we show that the chaotic attractors of the modified Chua’s circuit are globally attractive, with estimations given for the globally attractive set and positive invariant set. Then, we stu...

During evolution, genetic networks are rewired through strengthening or weakening their interactions to develop new regulatory schemes. In the galactose network, the GAL1/GAL3 paralogues and the GAL2 gene enhance their own expression mediated by the Gal4p transcriptional activator. The wiring strength in these feedback loops is set by the number of Gal4p binding sites. Here we show using synthe...