This article presents new current-mode oscillator circuits using CDTAs which is designed from block diagram. The proposed circuits consist of two CDTAs and two grounded capacitors. The condition of oscillation and the frequency of oscillation can be adjusted by electronic method. The circuits have high output impedance and use only grounded capacitors without any external resistor which is very...

Mats Høvin1, Alf Olsen2, Tor Sverre Lande1 and Chris Toumazou3 1Dept. of Informatics, University of Oslo, Blindern, N-0316 Oslo, Norway 2Schlumberger Geco-Prackla, Jongsåsveien 4, N-1300 Sandvika, Norway 3Dept. of Electrical & Electronic Engineering, Imperial College, Exhibition Road, London SW7 2BT, UK Abstract— This paper describes a new first and secondorder delta-sigma modulator (DSM) conce...

In a chain of mutually coupled oscillators, the coupling threshold for synchronization between the outermost identical oscillators decreases when a type of impurity (in terms of parameter mismatch) is introduced in the inner oscillator(s). The outer oscillators interact indirectly via dynamic relaying, mediated by the inner oscillator(s). We confirm this enhancing of critical coupling in the ch...

1. We use an electronic circuit to artificially electrically couple neurons. 2. Strengthening the coupling between an oscillating neuron and a hyperpolarized, passive neuron can either increase or decrease the frequency of the oscillator depending on the properties of the oscillator. 3. The result of electrically coupling two neuronal oscillators depends on the membrane potentials, intrinsic pr...

Phase-matched difference-frequency mixing in a thin GaSe crystal within the broad spectrum of 25-fs pulses from a Ti:sapphire oscillator multipass amplifier system permits the generation of few-cycle electric field transients, frequencies up to 30 THz, and amplitudes of more than 1 MV/cm. The field transients generated at a 1-kHz repetition rate are directly measured by electro-optic sampling b...

Exciton effects on soliton and bipolaron lattice states are investigated using an electron-lattice Peierls model with long-range Coulomb interactions. The Hartree-Fock (HF) approximation and the single-excitation configurationinteraction (single-CI) method are used to obtain optical absorption spectra. We discuss the following properties: (1) The attraction between the excited electron and the ...

A self–contained and tutorial presentation of the diffusion Monte Carlo method for determining the ground state energy and wave function of quantum systems is provided. First, the theoretical basis of the method is derived and then a numerical algorithm is formulated. The algorithm is applied to determine the ground state of the harmonic oscillator, the Morse oscillator, the hydrogen atom, and ...

We study the effect of a randomly modulated harmonic driving on the phase behavior of a nonlinear oscillator. A multiple-scale analysis shows that the system is formally equivalent to a rocked oscillator, in which a modulated harmonic driving locks the system at one of two phases, both of which are in quadrature with that of the driving. This theoretically predicted noise-induced bistable phase...

A novel VCO topology is proposed that combines the low power of –gm oscillators with the inherent buffering of Colpitts oscillators. Using this topology, a quadrature VCO (QVCO) was implemented in 0.13 μm digital CMOS consuming 32 mW at 20 GHz with just over 10% tuning range. The measured phase noise of the QVCO at 20.17 GHz is -102.41 dBc/Hz at 1 MHz offset. Because the load is isolated from t...

Perhaps the simplest Colpitts oscillator to construct and get running. Because there is no load on the inductor a high "Q" circuit results with a high L/C. Colpitts Oscillator Tutorial and the theory behind the design of the Colpitts Oscillator which uses a LC Oscillator tank circuit to generate sine waves. The Colpitts Oscillator Circuit Characterised By Tapping The Midpoint Of The Capacitive ...