Relaxation oscillator

About: Relaxation oscillator is a research topic. Over the lifetime, 1952 publications have been published within this topic receiving 22326 citations.

5.6 A 0.68nW/kHz supply-independent Relaxation Oscillator with ±0.49%/V and 96ppm/°C stability

Abstract: RC Relaxation Oscillators (RxO) are attractive for integrated clock sources compared to LC and ring oscillators (RO), as LC oscillators pose integration challenges and RO designs have limited voltage and temperature (V-T) stability. RxOs generate a clock whose time period (T P ) depends only on the timing resistor (R) and capacitor (C). Ideally, T P is independent of V-T; however, most RxOs use a reference voltage (V REF ) against which the voltage of C (Vc) is compared. Generating a V-T-independent V REF is non-trivial and causes variations in RxO frequency. A common approach is the use of VDD-independent current sources or band-gap or device-V t -based V REF [1]. The former are generally high-power options [2] while the latter is subject to process and V-T variations. A correct-by-design approach was adopted in [3] demonstrating VDD-independent operation by cancelling variations through differential sampling of VDD. Further, the power overhead of a supply-independent V REF is overcome by exploiting differential-integrator virtual ground. However, 4V2/R power in the RC tank and high-power VCO increase the energy/cycle.

PLL for regenerating a synchronizing signal from magnetic storage

Abstract: A phase-locked loop circuit, which obtains a signal synchronized with a phase of an input signal, including a synchronizing portion, and a data portion having a voltage controlled oscillator, a frequency phase comparator, a phase comparator, and a control circuit. The frequency phase comparator detects the phase difference and the frequency difference between the input signal and the output of the voltage controlled oscillator and the phase comparator detects the phase difference between the input signal and the output of the voltage controlled oscillator. The control circuit controls the voltage controlled oscillator, at least during a portion of the synchronizing signal portion, in accordance with the output of the frequency phase comparator, and, during the data signal portion, in accordance with the output of the phase comparator.

Electronic proximity sensor

Abstract: An electronic sensor of the contactless type has a free-running oscillator with internal positive feedback supplemented by an external negative feedback including a capacitive path whose impedance is normally high but is lowered in the presence of an object to be detected, thereby reducing the output signal of the oscillator from a normal amplitude above a predetermined level to a diminished amplitude below that level. The negative feedback is provided through an IGFET, e.g. of n-channel depletion type, with the aid of a capacitor bridging its source and gate electrodes to form with the external capacitance a voltage divider for the output signal of the oscillator.

Theoretical analysis of coupled oscillator array using resonant tunneling diodes in subterahertz and terahertz range

Abstract: Power combining with array configuration is an effective method for high output power in oscillators with resonant tunneling diodes (RTDs) in subterahertz and terahertz range. In this paper, output power and stability are analyzed for coupled oscillator array of RTDs. The coupled van der Pol equations are derived from the equivalent circuit for two-element oscillator arrays at first, and the condition in which only the fundamental oscillation mode stably oscillates is shown. The oscillation frequency of the array is single due to the mutual injection locking even if the individual frequencies of oscillator elements are different. Minimum difference between the individual frequencies to keep the mutual injection locking is analyzed. Experimental results are explained with theory. The analysis is extended to multielement oscillator arrays, and characteristics of oscillation modes, stability, combined output power, and locking range of the frequency difference between the elements are obtained. Theoretical combined output power increases with element number in proportion roughly to square of the element number if the frequency difference between the elements is small, and decreases with frequency difference. Different array configurations for stable and high-power operation are also discussed briefly.

Relaxation Oscillations in Point Contact Josephson Junctions.

Abstract: Negative resistance regions have been observed on the static I−V curves of point−contact Josephson junctions when dc biased with a low−impedance source. An equivalent circuit model has been developed which successfully explains the experimental results in terms of relaxation oscillations. It is also found that such junctions can be operated either as a one−port amplifier for signals at 5 MHz or as a 36−GHz heterodyne mixer with large conversion gain.