A circuit device includes an oscillation circuit and a processing circuit that generates capacitance control data. The oscillation circuit includes a variable capacitance circuit whose capacitance value is variably controlled based on the capacitance control data, and an oscillation frequency thereof is controlled based on the capacitance value of the variable capacitance circuit. The variable capacitance circuit includes a capacitor array. The capacitor array includes a plurality of capacitors each having a binary-weighted capacitance value, and a plurality of switches that are on-off controlled based on the capacitance control data. The processing circuit outputs the capacitance control data, which is subjected to dithering, so as to switch the capacitance value of the variable capacitance circuit between a first capacitance value and a second capacitance value in a time division manner.

A circuit device includes an oscillation circuit and a processing circuit. The oscillation circuit includes a variable capacitance circuit configured by a capacitor array and oscillates at an oscillation frequency corresponding to the capacitance value of the variable capacitance circuit. First temperature data and second temperature data subsequent to the first temperature data are input to the processing circuit as temperature data. In the period between the start of the capacitance control based on the first temperature data and the start of the capacitance control based on the second temperature data, the processing circuit switches the first capacitance control data corresponding to the first temperature data and the second capacitance control data different from the first capacitance control data in a time-division manner to be output to the variable capacitance circuit.

A circuit device includes an oscillation circuit and a processing circuit. The oscillation circuit includes a variable capacitance circuit configured by a capacitor array and oscillates at an oscillation frequency corresponding to the capacitance value of the variable capacitance circuit. First temperature data and second temperature data subsequent to the first temperature data are input to the processing circuit as temperature data. In the period between the start of the capacitance control based on the first temperature data and the start of the capacitance control based on the second temperature data, the processing circuit switches the first capacitance control data corresponding to the first temperature data and the second capacitance control data different from the first capacitance control data in a time-division manner to be output to the variable capacitance circuit.

Systems and methods for compensating a non-linearity of a digitally controlled oscillator (DCO) are presented. Data comprising a plurality of silicon measurements is received. Each silicon measurement in the plurality of silicon measurements is compared to an ideal value. Based on the comparing, a plurality of compensation vectors is generated. Each compensation vector comprises at least one silicon measurement. At least one frequency is adjusted based on a compensation vector in the plurality of compensation vectors. A digitally-controlled oscillator frequency is generated based on the adjusted at least one frequency.

A method and apparatus for performing a two-point calibration of a VCO in a PLL is disclosed. The method includes determining a first steady state tuning voltage of the VCO with no modulation voltage applied. Thereafter, an iterative process may be performed wherein a modulation voltage is applied to the VCO (along with the tuning voltage) and a modified divisor is applied to the divider circuit in the feedback loop. During each iteration, after the PLL is settled, the tuning voltage is measured and a difference between the current value and the first value is determined. If the current and first values of the turning voltage are not equal, another iteration may be performed, modifying at least one of the modulation voltage and the divisor, and determining the difference between the current and first values of the tuning voltage.

A transmission system comprising: an output-terminal configured to provide an output-signal; a phase-shift oscillator comprising a plurality of phase-shifters, each configured to provide one of a plurality of phase-shifted-signals; and a controller configured to provide a selected one of the phase-shifted-signals to the output-signal as a transition in the output-signal, at an instant in time that is based on one or more of the plurality of phase-shifted-signals.

Certain aspects relate to a semiconductor die. The semiconductor die includes a voltage-controlled oscillator (VCO), wherein the VCO includes a resonant capacitor, and a resonant inductor coupled in parallel with the resonant capacitor. The resonant inductor includes a first elongated portion and a second elongated portion that are parallel with each other. The semiconductor die also includes a voltage supply line configured to route a supply voltage to the VCO, wherein the voltage supply line includes a first portion that runs parallel with the first and second elongated portions of the resonant inductor and is located between the first and second elongated portions of the resonant inductor.

Systems and methods for compensating a non-linearity of a digitally controlled oscillator (DCO) are presented. Data comprising a plurality of silicon measurements is received. Each silicon measurement in the plurality of silicon measurements is compared to an ideal value. Based on the comparing, a plurality of compensation vectors is generated. Each compensation vector comprises at least one silicon measurement. At least one frequency is adjusted based on a compensation vector in the plurality of compensation vectors. A digitally-controlled oscillator frequency is generated based on the adjusted at least one frequency.

Systems and methods for compensating a non-linearity of a digitally controlled oscillator (DCO) are presented. Data comprising a plurality of silicon measurements is received. Each silicon measurement in the plurality of silicon measurements is compared to an ideal value. Based on the comparing, a plurality of compensation vectors is generated. Each compensation vector comprises at least one silicon measurement. At least one frequency is adjusted based on a compensation vector in the plurality of compensation vectors. A digitally-controlled oscillator frequency is generated based on the adjusted at least one frequency.

It is often desirable to transmit data between circuits or components operating at a relatively high voltage and circuits operating at a relatively low voltage. Such a task can be performed by use of an isolator. Some isolator designs use magnetic coupling to transfer the data as this is more robust against inadvertently transmitting high voltage transients than capacitor based isolators. However it is often desirable to encode the data for exchange across the transformer of the isolator and decode after transmission across the transformer. This requires power for the encoding and decoding circuits. To ensure both sides are powered, power may be transferred by another transformer. The transformer primary is driven by an oscillating signal. The system disclosed in some embodiments herein varies the frequency of the oscillating signal to mitigate the risk of it interfering with other circuits or systems associated with the isolator.