A crystal oscillation circuit includes: two resistors; two capacitors; and an inverter. A crystal oscillation circuit for the crystal oscillation circuit includes: arranging the two resistors in parallel with the two capacitors such that an area of a wiring feedback path from an output terminal to an input terminal of the inverter is minimized, and arranging terminals of the two capacitors to be connected to ground close to each other.

A CMTI circuit includes a first detector that receives one or more output signals from an oscillator and a first enable signal and generates a first detection signal when the received output signals are determined to be substantially not oscillating at a first time. The CMTI circuit further includes a first activation signal generator that generates a first activation signal in response to the first detection signal to resume oscillation of the output signals.

An oscillator circuit is provided, which relates to the field of electronic technologies, to improve performance of an oscillator. The oscillator circuit includes: a first amplifier (Am1) and a second amplifier (Am2), where the first amplifier (Am1) and the second amplifier (Am2) are switchable, and the oscillator circuit is operable in an inductive feedback mode or a negative resistance mode through switching. The oscillator circuit further includes a capacitive element and an inductive element, where the inductive element includes a tapped inductor that includes four terminals (V1, V2, V3, and V4), two of the four terminals are coupled to differential inputs of the first amplifier (Am1) and differential outputs of the second amplifier (Am2), and the other two terminals are coupled to differential outputs of the first amplifier (Am1).

An oscillator includes a first resonator element, a circuit element configured to oscillate the first resonator element to generate an oscillation signal, a first package which includes a substrate, and has a housing space configured to house the first resonator element and the circuit element at one principal surface side of the substrate, a second resonator element which is disposed at another principal surface side of the substrate, and an oscillation frequency of which is controlled based on the oscillation signal, and a leg part which is disposed at the another principal surface side of the substrate, and which is arranged so as to surround the second resonator element in a plan view of the substrate.

The present disclosure provides a voltage controlled oscillator for flipped and complementary low noise. The voltage controlled oscillator includes a first resonant cavity, a second resonant cavity, and an associated circuit. The associated circuit is configured to connect the first resonant cavity and the second resonant cavity in series and couple the first resonant cavity and the second resonant cavity. A resonant frequency of the first resonant cavity and a resonant frequency of the second resonant cavity satisfy a first preset condition.

An integrated circuit apparatus includes an oscillation circuit that generates an oscillation signal by using a resonator, an output buffer circuit that outputs a clock signal based on the oscillation signal, a DC voltage generation circuit that generates a DC voltage used to generate the oscillation signal or the clock signal, a power source pad to which a power source voltage is supplied, a ground pad to which a ground voltage is supplied, and a clock pad via which the clock signal is outputted. The ground pad and the DC voltage generation circuit are disposed so as to overlap with each other in the plan view.

An oscillating signal generator circuit includes an oscillator circuit, a feedback circuit, and a voltage regulator circuit. The oscillator circuit is configured to generate a first and second oscillating signal at a first and second output terminal according to a first reference voltage. The first and second oscillating signals are a differential pair of signals. The oscillator circuit includes a common mode sensing circuit coupled between the first and second output terminals. The common mode sensing circuit is configured to sense a common mode component of the first and second oscillating signals so as to generate a sense voltage. The feedback circuit, coupled to the common mode sensing circuit, is configured to generate a feedback voltage according to the sense voltage. The voltage regulator circuit is coupled to the oscillator circuit and the feedback circuit, and configured to regulate a supply voltage so as to generate the first reference voltage.

An oscillator circuit is provided, which relates to the field of electronic technologies, to improve performance of an oscillator. The oscillator circuit includes: a first amplifier (Am1) and a second amplifier (Am2), where the first amplifier (Am1) and the second amplifier (Am2) are switchable, and the oscillator circuit is operable in an inductive feedback mode or a negative resistance mode through switching. The oscillator circuit further includes a capacitive element and an inductive element, where the inductive element includes a tapped inductor that includes four terminals (V1, V2, V3, and V4), two of the four terminals are coupled to differential inputs of the first amplifier (Am1) and differential outputs of the second amplifier (Am2), and the other two terminals are coupled to differential outputs of the first amplifier (Am1).

An apparatus is provided which comprises: a crystal having an input and an output; a first interconnect line having first and second ends, wherein the first end is coupled to the input; a second interconnect line having first and second ends, wherein the first end is coupled to the output; a first capacitor coupled to the input and ground; and a second capacitor coupled to the second end of the second interconnect line. An apparatus is provided which comprises: a high pass filter; a pair of AC coupling capacitors coupled to the high pass filter; a low pass filter coupled to the pair of AC coupling capacitors; and an analog to digital converter (ADC) coupled to the low pass filter.

A crystal oscillator is provided. The crystal oscillator includes a crystal resonator including a pair of terminals and being capable of oscillating at a fundamental resonance frequency and at least one overtone resonance frequency. Further, the crystal oscillator includes an inverter circuit coupled between the pair of terminals. The crystal oscillator additionally includes a suppression circuit configured to suppress oscillation of the crystal resonator at the fundamental resonance frequency. Further, the crystal oscillator includes a control circuit configured to control a switch circuit for selectively coupling the suppression circuit to the crystal resonator.