A power inverter, such as a synchronous buck power inverter, that is configured with a high frequency switching control having a (PWM) controller and sensing circuit. Controller provides a low frequency oscillating wave to effect switching control on a synchronous-buck circuit portion that includes a plurality of switches to invert every half cycle of the frequency provided by controller. The inverting process thus creates a positive and negative transition of the oscillating wave signal. A low frequency switching stage includes a further plurality of switches configured to operate as zero voltage switching (ZVS) and zero current switching (ZCS) drives Charge on an output capacitor is discharged to zero on every zero crossing of low frequency switching stage and advantageously discharges energy every half cycle. During this discharge of energy, the zero crossing distortion in the low frequency sine wave is greatly reduced.

A power inverter, such as a synchronous buck power inverter, that is configured with a high frequency switching control having a (PWM) controller and sensing circuit. Controller provides a low frequency oscillating wave to effect switching control on a synchronous-buck circuit portion that includes a plurality of switches to invert every half cycle of the frequency provided by controller. The inverting process thus creates a positive and negative transition of the oscillating wave signal. A low frequency switching stage includes a further plurality of switches configured to operate as zero voltage switching (ZVS) and zero current switching (ZCS) drives Charge on an output capacitor is discharged to zero on every zero crossing of low frequency switching stage and advantageously discharges energy every half cycle. During this discharge of energy, the zero crossing distortion in the low frequency sine wave is greatly reduced.

A crystal oscillator and a method are provided for adjusting an oscillation frequency. The crystal oscillator includes: a first oscillator circuit, a frequency control circuit and a crystal; where the first oscillator circuit is configured to output a first drive signal having a first oscillation frequency to drive the crystal, and the frequency control circuit is configured to determine a frequency control amount according to a feature of an electrical signal flowing through the crystal under driving of the first drive signal, and adjust the first oscillation frequency according to the frequency control amount. When the technical solutions are applied to scenarios where the crystal oscillator is enabled to quickly en-oscillate, a natural en-oscillation cycle of the crystal oscillator may be shortened, and the en-oscillation speed is increased.

A crystal oscillator and a method are provided for adjusting an oscillation frequency. The crystal oscillator includes: a first oscillator circuit, a frequency control circuit and a crystal; where the first oscillator circuit is configured to output a first drive signal having a first oscillation frequency to drive the crystal, and the frequency control circuit is configured to determine a frequency control amount according to a feature of an electrical signal flowing through the crystal under driving of the first drive signal, and adjust the first oscillation frequency according to the frequency control amount. When the technical solutions are applied to scenarios where the crystal oscillator is enabled to quickly en-oscillate, a natural en-oscillation cycle of the crystal oscillator may be shortened, and the en-oscillation speed is increased.

A power inverter, such as a synchronous buck power inverter, that is configured with a high frequency switching control having a (PWM) controller and sensing circuit. Controller provides a low frequency oscillating wave to effect switching control on a synchronous-buck circuit portion that includes a plurality of switches to invert every half cycle of the frequency provided by controller. The inverting process thus creates a positive and negative transition of the oscillating wave signal. A low frequency switching stage includes a further plurality of switches configured to operate as zero voltage switching (ZVS) and zero current switching (ZCS) drives Charge on an output capacitor is discharged to zero on every zero crossing of low frequency switching stage and advantageously discharges energy every half cycle. During this discharge of energy, the zero crossing distortion in the low frequency sine wave is greatly reduced.

A power inverter, such as a synchronous buck power inverter, that is configured with a high frequency switching control having a (PWM) controller and sensing circuit. Controller provides a low frequency oscillating wave to effect switching control on a synchronous-buck circuit portion that includes a plurality of switches to invert every half cycle of the frequency provided by controller. The inverting process thus creates a positive and negative transition of the oscillating wave signal. A low frequency switching stage includes a further plurality of switches configured to operate as zero voltage switching (ZVS) and zero current switching (ZCS) drives Charge on an output capacitor is discharged to zero on every zero crossing of low frequency switching stage and advantageously discharges energy every half cycle. During this discharge of energy, the zero crossing distortion in the low frequency sine wave is greatly reduced.

An adaptive constant current engine (ACCE) to control a current of a target load device at a constant level is disclosed. The ACCE includes a closed feedback loop which generates a sensed current that represents a load current conducted by the target load device and then compares the sensed current to a reference current. Based on this comparison, the circuit can output a voltage to control the current conducted by the target load device. The disclosed ACCE adapts the comparison to an operating voltage of the target load device in order to provide electrical conditions at a reference node receiving a reference current that are the same as electrical conditions at a sensing node receiving a sensing current. Accordingly, the ACCE can generate very accurate comparisons regardless of variations in the operating voltage of the target load device.

An oscillator and an operation method thereof are provided. The oscillator includes a current source, a memristor, a switching circuit, and a control circuit. The switching circuit is coupled to the current source and the memristor. The switching circuit is configured to transmit a bias current provided by the current source to the memristor, and determine a flow direction of the bias current in the memristor according to at least one control signal. The control circuit is coupled to the switching circuit to provide the at least one control signal. The control circuit is configured to detect a representative voltage of the memristor. The control circuit changes the at least one control signal according to a relationship between the representative voltage, a first threshold voltage, and a second threshold voltage to change the flow direction of the bias current in the memristor.

An oscillator and an operation method thereof are provided. The oscillator includes a current source, a memristor, a switching circuit, and a control circuit. The switching circuit is coupled to the current source and the memristor. The switching circuit is configured to transmit a bias current provided by the current source to the memristor, and determine a flow direction of the bias current in the memristor according to at least one control signal. The control circuit is coupled to the switching circuit to provide the at least one control signal. The control circuit is configured to detect a representative voltage of the memristor. The control circuit changes the at least one control signal according to a relationship between the representative voltage, a first threshold voltage, and a second threshold voltage to change the flow direction of the bias current in the memristor.

A multimode, multicore inductor-capacitor (LC) oscillator having an increased oscillation frequency tuning range, and related method, are provided. The oscillation frequency tuning range of existing oscillators is limited. LC oscillators are known to have very low phase noise but a narrow frequency tuning range. The present oscillator has at least two LC oscillator cores and is capable of operating in multiple different modes of oscillation thereby increasing its overall oscillation frequency tuning range. A set of programmable amplifier pairs is used to force particular relative oscillation phases at the nodes of the multiple cores of the oscillator to realize one or more additional modes of oscillation for the oscillator. The additional oscillation mode increases the frequency tuning range of the oscillator.