An electronic device may include a transceiver with mixer circuitry that up-converts or down-converts signals based on a voltage-controlled oscillator (VCO) signal. The transceiver circuitry may include first, second, third, and fourth VCOs. Each VCO may include a VCO core that receives a control voltage and an inductor coupled to the VCO core. Fixed linear capacitors may be coupled between the VCO cores. A switching network may be coupled between the VCOs. Control circuitry may place the VCO circuitry in one of four different operating modes and may switch between the operating modes to selectively control current direction in each of the inductors. The VCO circuitry may generate the VCO signal within a respective frequency range in each of the operating modes. The VCO circuitry may exhibit a relatively wide frequency range across all of the operating modes while introducing minimal phase noise to the system.

A voltage-controlled oscillator includes a first transistor, a second transistor, an inductive impedance element, a first variable capacitive impedance element, and a second variable capacitive impedance element. The first transistor has a source coupled to a first power source, a drain coupled to a first node, and a gate coupled to a second node. The second transistor has a source coupled to the first power source, a drain coupled to the second node, and a gate coupled to the first node. The inductive impedance element has a first terminal coupled to the first node and a second terminal coupled to the second node. The first variable capacitive impedance element has a first terminal coupled to the first node and a second terminal coupled to a third node. The second variable capacitive impedance element has a first terminal coupled to the second node and a second terminal coupled to the third node.

An example voltage controlled oscillator includes an inductor, a capacitor coupled to the inductor, and a signal source coupled to the inductor and the capacitor to sustain an oscillating signal. The voltage controlled oscillator includes a first varactor coupled to the inductor and the capacitor, wherein the first varactor is biased by a first bias voltage and is configured to change a frequency of the oscillating signal based on a first control voltage signal. The voltage controlled oscillator includes a second varactor coupled to the inductor, the capacitor, and the first varactor, wherein the second varactor is biased by a second bias voltage and is configured to compensate temperature variation of the frequency of the oscillating signal over a plurality of frequency bands based on second control voltage signal.

An element includes a coupling line in which a first conductor layer, a dielectric layer, and a second conductor layer are stacked in this order, and which is connected to the second conductor layer in order to mutually synchronize a plurality of antennas at a frequency of a terahertz wave; and a bias line connecting a power supply for supplying a bias signal to a semiconductor layer and the second conductor layer. A wiring layer in which the coupling line is formed and a wiring layer in which the bias line is formed are different layers. The bias line is disposed in a layer between the first conductor layer and the second conductor layer.

A voltage controlled oscillator (VCO) circuitry includes a varactor array. The varactor array includes a first varactor unit including a first varactor, a second varactor, and first switch circuitry. The first varactor is connected to a first node and a second node, and the second varactor is connected to the second node and a third node. The second node receives a voltage control signal. The first switch circuitry is electrically coupled to the first node and the third node, and selectively electrically couples a first voltage signal to the first node and the third node based on a first control signal.

A programmable variable capacitor includes a fixed varactor controlled by a control voltage connected in a first polarity and a plurality of contingent varactors conditionally controlled by the control voltage in accordance with a plurality of logical signals, respectively, each of said plurality of contingent varactors having: a first varactor controlled by a first voltage connected in the first polarity, a second varactor controlled by a second voltage connected in a second polarity, a first multiplexer configured to output the first voltage by selecting between a first DC (direct-current) voltage and the control voltage in accordance with a respective logical signal among said plurality of logical signals, and a second multiplexer configured to output the second voltage by selecting between a second DC voltage and a medium DC voltage in accordance with the respective logical signal.

The disclosure relates to a radio frequency oscillator. The radio frequency oscillator includes a resonator circuit being resonant at an excitation of the resonator circuit in a differential mode and at an excitation of the resonator circuit in a common mode. The resonator circuit has a differential mode resonance frequency at the excitation in the differential mode, and the resonator circuit has a common mode resonance frequency at the excitation in the common mode. A first excitation circuit is configured to excite the resonator circuit in the differential mode to obtain a differential mode oscillator signal oscillating at the differential mode resonance frequency, and a second excitation circuit is configured to excite the resonator circuit in the common mode to obtain a common mode oscillator signal oscillating at the common mode resonance frequency.

A differential oscillator includes a differential circuit and a transformer-coupled band-pass filter (BPF) coupled between first and second output nodes. The BPF includes a coupling device coupled between the output nodes and a transformer including first and second windings in a metal layer of an IC. The first winding includes first and second conductive structures coupled to the first output node and a voltage node, respectively, and a third conductive structure including first and second extending portions connected to the first and second conductive structures, respectively. The second winding includes a fourth conductive structure including a third extending portion coupled to the voltage node and a fourth extending portion coupled to the second output node. The third extending portion is between the second conductive structure and the first extending portion, and the fourth extending portion is between the first conductive structure and the second extending portion.

A technology related to an electronic circuit, specifically, a phase locked loop or a frequency synthesizing apparatus, is disclosed. The frequency synthesizing apparatus includes an injection locked frequency divider and a replica frequency divider having the same circuit configuration as the injection locked frequency divider. A control value required for self-oscillating at a target frequency using the replica frequency divider is determined. When the injection locked frequency divider fails injection locking on a first attempt, the injection locking may be attempted using the determined control value. On the first attempt, the control value of the injection locked frequency divider may be determined and stored in advance according to a temperature and a supply voltage.

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.