A CMOS gain element is disclosed herein. Also disclosed herein are splitters, comprising the CMOS gain element, and local oscillator distribution circuitry comprising the splitters and the CMOS gain elements. Semiconductor devices comprising the local oscillator distribution circuitry may have smaller footprints and reduced power consumption relative to prior art devices.

A class-E power oscillator (PO) is disclosed. The class-E PO includes a first inductor, a switch, a first capacitor, a resonant circuit, and a feedback network. The first inductor is coupled in series to a first power supply. The switch is connected between the first inductor and a primary common node. The first capacitor is connected between the first inductor and the primary common node. The resonant circuit includes a second inductor, a second capacitor, and a resistor. The second inductor is connected between the first inductor and the primary common node. The second capacitor is connected between the first inductor and the primary common node, and is coupled in series to the second inductor. The resistor is connected between the first inductor and the primary common node, and is coupled in series to the second inductor. The feedback network is connected between the switch and a feedback node. The feedback node is located between the second inductor and the second capacitor. The feedback network is configured to periodically turn the switch on and off based on a resonance frequency of the resonant circuit.

A voltage-controlled oscillator having a triple-push structure is disclosed. The voltage-controlled oscillator having a triple-push structure may include: a voltage-controlled oscillation part including a multiple number of oscillation circuits configured to output an output signal based on a control voltage, where the multiple oscillation circuits are connected in a triple-push structure; a multiple number of phase shifters connected respectively to the output ends of the oscillation circuits and configured to change a phase of the output signals outputted from the output ends of the oscillation circuits; and an output part configured to output a final output signal by adding the output signals that are outputted with changed phases from the multiple phase shifters.

An oscillator circuit uses a comparator, and the oscillator circuit controls charge-discharge of the Miller capacitance between the gate and the drain of a MOSFET serving as an amplifier of the gain unit and the gate capacitance of the MOSFET, and enables the comparator output to follow a relatively high-frequency control signal that is input externally. The oscillator circuit uses a comparator having a differential unit and a gain unit. The oscillator circuit includes a charge-discharge control unit that connects to the output of the differential unit and is configured to control charge-discharge of the Miller capacitance between the gate and the drain of a MOSFET (N2) serving as an amplifier of the gain unit and the gate capacitance of the MOSFET, and an output control unit configured to control the output of the gain unit.

A voltage controlled oscillator (VCO) is disclosed to provide reduced phase noise at higher operating frequencies. A buffer-first VCO configured according to an embodiment includes multiple VCO core circuits configured to provide synchronously tuned oscillator signals. Each VCO core circuit is coupled to a summing node through a buffer circuit that generates uncorrelated phase noise such that the summing node provides a summation output of the oscillator signals with reduced phase noise. A multiplexer-less VCO configured according to an embodiment includes multiple buffer-first VCO circuits configured to provide oscillator signals covering a range of frequencies. Each buffer-first VCO circuit is controlled or selected by an enable signal. Buffer circuits are configured to select one of the buffer-first VCO circuits for coupling to a transmission line during a given time period based on the enable signal. The transmission line is terminated in a matched impedance at each end of the line.

A two-wire displacement sensor device includes an LC oscillation circuit including a coil whose inductance changes in accordance with a displacement amount of an object and an oscillation unit provided with capacitors and amplifying elements; and an interface unit serving as a signal output unit and a power supply input unit. The interface unit includes a constant current circuit that outputs at least two current values.

A near field communication (NFC) reader is disclosed. The NFC reader includes an antenna front-end that includes a low pass filter, a matching circuit and an antenna coil. The NFC reader also includes a NFC controller. The NFC controller includes an oscillator coupled to the antenna front-end and the NFC controller is configured to detect a presence of an object in proximity of the antenna front-end using one or more changes in an output of the oscillator. The antenna front-end creates a tank circuit for the oscillator.

Various embodiments of the invention relate to a Multi-Band Voltage Controlled Oscillator (VCO). The multi-band VCO features a coupled-inductor based resonator. The resonator comprises a primary path and a secondary path inductively coupled to the primary path. The primary path comprises multiple LC tuning stages coupled in series with each stage having an adjustable capacitor and a primary inductor inductively coupled to the secondary path. The secondary path comprises multiple secondary inductors inductively coupled to respective primary inductors in the primary path. Furthermore, the secondary path comprises a plurality of controllable switches which are controlled to switch ON or OFF simultaneously to engage/disengage the inductive coupling between the primary path and the secondary path. Incorporating multiple LC tuning stages lowers voltage swing across each tuning stages, thus minimizing phase noise caused by nonlinearity in the resonator.

A FET driving circuit includes: two inputs for inputting a DC voltage; two outputs respectively connected to gate and source electrodes of a FET; a switch; a resonant capacitance connected between both ends of the switch; and an LC resonance circuit connected between the inputs and both ends of the switch. When the two inputs are shorted, frequency characteristics of an impedance of the LC resonance circuit include, in order from a low to a high-frequency side, first to fourth resonant frequencies. The first resonant frequency is higher than a switching frequency of the switch, the second resonant frequency is around double the switching frequency, the fourth resonant frequency is around four times the switching frequency, and the impedance has local maxima at the first resonant frequency and the third resonant frequency and local minima at the second resonant frequency and the fourth resonant frequency.

A device [200, para. 16] includes a transformer [206, para. 16] that further includes a primary [208, para. 16] and a secondary [210, para. 16] windings. A switch [212, para. 20] is coupled to the primary winding, and this switch is controlled by the received digital input signal. An oscillator [216, para. 17] is further formed on the secondary winding where the oscillator oscillates in response to variations of the received input signal. [para. 19] A detector [218, para. 17] coupled to the oscillator will then detect the oscillations in response to the variations of the received input signal. Thereafter, the detector generates a digital output [108, para. 14] based on the detected oscillations. [para. 25]