There is disclosed herein clock generation circuitry, in particular rotary travelling wave oscillator circuitry. Such circuitry comprises a pair of signal lines connected together to form a dosed loop and arranged such that they define at least one transition section where both said lines in a first portion of the pair cross from one lateral side of both said lines in a second portion of the pair to the other lateral side of both said lines in the second portion of the pair.

A high frequency push-push oscillator is disclosed. The high frequency push-push oscillator includes a resonant circuit, including tank transmission lines or an inductor capacitor (LC) tank circuit, for generating a differential signal having a resonant frequency, and a Gm-core circuit for converting the differential signal to an output signal having an output frequency that is higher than the resonant frequency. The Gm-core circuit includes cross-coupled first and second transistors having first and second gates, drains, and sources, respectively, and first and second gate transmission lines. The first and second drains are in electrical communication with the resonant circuit. The first gate transmission line is joined with the first gate and the resonant circuit and the second gate transmission line is joined with the second gate and the resonant circuit. The Gm-core circuit includes a differential transmission line positioned between the first and second gates of the first and second transistors.

Rotary traveling wave oscillator-based (RTWO-based) frequency multipliers are provided herein. In certain embodiments, an RTWO-based frequency multiplier includes an RTWO that generates a plurality of clock signal phases of a first frequency, and an edge combiner that processes the clock signal phases to generate an output clock signal having a second frequency that is a multiple of the first frequency. The edge combiner can be implemented as a logic-based combining circuit that combines the clock signal phases from the RTWO. For example, the edge combiner can include parallel stacks of transistors operating on different clock signal phases, with the stacks selectively activating based on timing of the clock signal phases to generate the output clock signal of multiplied frequency.

Rotary traveling wave oscillator-based (RTWO-based) frequency multipliers are provided herein. In certain embodiments, an RTWO-based frequency multiplier includes an RTWO that generates a plurality of clock signal phases of a first frequency, and an edge combiner that processes the clock signal phases to generate an output clock signal having a second frequency that is a multiple of the first frequency. The edge combiner can be implemented as a logic-based combining circuit that combines the clock signal phases from the RTWO. For example, the edge combiner can include parallel stacks of transistors operating on different clock signal phases, with the stacks selectively activating based on timing of the clock signal phases to generate the output clock signal of multiplied frequency.

A transformer based voltage controlled oscillator (VCO) is provided with a primary resonant circuit having a first inductor connected in parallel with a variable first capacitance circuit. A secondary resonant circuit is formed from a second inductor connected in parallel with a variable second capacitance circuit, and also includes a mode control circuit. The mode control circuit controls the direction of current flow through the secondary resonant circuit inductor. The first and second inductors are inductively mutually coupled in either an even mode or an odd mode in response to the mode control circuit. The VCO supplies a first resonant frequency in response to even mode operation, or a second resonant frequency, greater than the first resonant frequency, responsive to odd mode operation. The VCO may include a first electrically tunable varactor shunted across the first capacitance circuit and a second electrically tunable varactor shunted across the second capacitance circuit.

A high frequency push-push oscillator is disclosed. The high frequency push-push oscillator includes a resonant circuit, including tank transmission lines or an inductor capacitor (LC) tank circuit, for generating a differential signal having a resonant frequency, and a Gm-core circuit for converting the differential signal to an output signal having an output frequency that is higher than the resonant frequency. The Gm-core circuit includes cross-coupled first and second transistors having first and second gates, drains, and sources, respectively, and first and second gate transmission lines. The first and second drains are in electrical communication with the resonant circuit. The first gate transmission line is joined with the first gate and the resonant circuit and the second gate transmission line is joined with the second gate and the resonant circuit. The Gm-core circuit includes a differential transmission line positioned between the first and second gates of the first and second transistors.

Articles including oscillating units and methods for producing the same are disclosed. An example article includes one or more oscillator units, where each oscillator unit comprises: a micro strip transmission line extending from a first end to a second end. A first termination impedance is coupled to the first end and a second termination impedance is coupled to the second end. A first transistor is coupled between the first end and the midpoint; and a second transistor is coupled between the midpoint and the second end. The micro strip transmission line has a midpoint between the first end and the second end; and each oscillator unit generates a standing wave having a predetermined wavelength in the micro strip transmission line.

Rotary traveling wave oscillators (RTWOs) with distributed stubs are provided. In certain embodiments, an RTWO includes segments that are implemented using distributed stubs to mitigate flicker noise upconversion arising from transmission line dispersion. For example, a distance between the distributed stubs can be selected to intentionally generate a phase difference between transmission line modes, thereby cancelling out phase shifts due to transmission line dispersion. In particular, each segment is subdivided into multiple transmission line sections with a maintaining amplifier electrically connected to one of the sections and a tuning capacitor array connected to adjacent transmission line sections.

Apparatus and methods for rotary traveling wave oscillators (RTWOs) are provided herein. In certain configurations, an RTWO includes a differential transmission line connected in a ring and a plurality of segments distributed around the ring. The segments include metal stubs extending from the RTWO's differential transmission line. The metal stubs aid in providing access to additional layout resources for tuning capacitors and other circuitry of the RTWO's segments, while permitting the length of RTWO's ring to be relative short. Thus, the metal stubs do not inhibit the RTWO from operating with relatively high oscillation frequency, while providing connectivity to tuning capacitors that tune the RTWO's oscillation frequency over a wide tuning range and/or provide fine frequency step size.

An oscillator includes a first output node and a second output node. There is a tank circuit coupled between the first output node and the second output node. There is a first transistor having a first node, a second node coupled to a current source, and a control node coupled to the second output node. There is a second transistor having a first node, a second node coupled to the current source, and a control node coupled to the first output node. There is a first inductor coupled in series between the first node of the first transistor and the first output node. There is a second inductor coupled in series between the first node of the second transistor and the second output node.