Abstract: Integrated circuit oscillators include a cascaded arrangement of first and second all-pass networks containing a resonator therein, such as a crystal-based resonator. The second all-pass network is configured to provide negative feedback to the first all-pass network at DC (i.e., very low frequencies) and is further configured to provide positive feedback with 90 degrees of phase to the first all-pass network at the resonant frequency of the resonator, which may be the third overtone frequency of a crystal resonator. The first all-pass network includes the resonator and the second all-pass network includes a resistor having resistance matched to a motional resistance of the resonator at the resonant frequency.

Abstract: An oscillation circuit includes a resonance circuit and an amplifier circuit. The resonance circuit includes an inner capacitor to be disposed inside a semiconductor integrated circuit, and an outer capacitor and an outer inductor to be disposed outside the semiconductor integrated circuit. The amplifier circuit includes an input terminal and an output terminal both connected to the resonance circuit. Further, the resonance circuit includes a first closed circuit portion including the inner capacitor, the outer inductor, and a first wiring portion for connecting the inner capacitor and the outer inductor. The resonance circuit further includes a second closed circuit portion including the outer capacitor, the outer inductor, and a second wiring portion for connecting the outer capacitor and the outer inductor. The second closed circuit portion has a wiring resistance smaller than that of the first closed circuit portion.

Abstract: A controlled oscillator includes, connected in parallel, a capacitor configured to be tuneable based upon a first signal, an inductor, and an active impedance. The active impedance is formed by a pair of cross-coupled transistors connected so as to produce a negative resistive component at the terminals of the active impedance. Circuitry produces a degeneracy tuneable by a second signal in the cross-coupled pair, such that the cross-coupled pair produces a capacitive component tuneable based upon the second signal at the terminals of the active impedance.

Abstract: A technique to use an auxiliary varactor coupled to a tuning varactor, in which a temperature compensated bias signal adjusts a bias on the auxiliary varactor to maintain a voltage controlled oscillator (VCO) from drifting in frequency as operating temperature for the VCO changes.

Abstract: A piezoresistive MEMS oscillator comprises a resonator body, first and second drive electrodes located adjacent the resonator body for providing an actuation signal; and at least a first sense electrode connected to a respective anchor point. The voltages at the electrodes are controlled and/or processed such that the feedthrough AC current from one drive electrode to the sense electrode is at least partially offset by the feedthrough AC current from the other drive electrode to the sense electrode.

Abstract: A variable modulus sigma delta (??) modulator for a fractional-N frequency synthesizer in accordance with the present invention may include an integer division unit; a pulse-width modulation (PWM) generator, a ?? noise-shaping unit, a first input FRAC for receiving a first programmable integer, and a second input MOD for receiving a second input, wherein the integer division unit is configured to perform a translation from the first input and the second input into a first output FRAC? and a second output R, the PWM generator is configured to receive the second input MOD and the second output R, and generate a modulated pulse signal, and the ?? noise-shaping unit is configured to receive the first output and the modulated pulse signal, and generate a sequence whose average equals approximately the first input over the second input.

Abstract: The present invention is a high power direct transmitter with frequency-shift keying (FSK) modulation. The transmitter implements a high power, high efficiency power voltage-controlled oscillator (VCO) which allows for production of a modulated RF signal at the final stage (ex.—right at the antenna), thereby eliminating all driving stage power amplification and frequency translation. The transmitter further provides a low SWAP-C alternative to currently available solutions.

Abstract: A ring oscillator includes a plurality of inverting delay units serially connected in a form of a ring. Each of the inverting delay units receives an input signal and generates an output signal, and each of the inverting delay units includes a buffer and a delay circuit. The buffer has an input terminal and an output terminal. The input terminal receives the input signal, and the output terminal generates a buffered input signal. The delay circuit serves to provide a first time delay and a second time delay. Besides, according to a voltage level of the buffered input signal, the delay circuit provides a first reference voltage to generate the output signal after the first time delay or provides a second reference voltage to generate the output signal after the second time delay.

Abstract: The present invention is an oscillator which implements matched resonators which are driven at a same frequency, one hundred-eighty degrees out-of-phase. The resonators may be implemented in a same plane of a printed circuit board and located adjacent to each other, thus the resonators are affected by a same (ex.—same magnitude of) vibration interference. However, in the oscillator embodiments described herein, the vibration interference component cancels out of (ex.—is eliminated from) the oscillator output signal, leaving only the desired component.