Examples described herein generally relate to a temperature-locked loop for optical elements. In an example, a device includes a controller and a digital-to-analog converter (DAC). The controller includes a DC-controllable transimpedance stage (DCTS), a slicer circuit, and a processor. The DCTS is configured to be coupled to a photodiode. An input node of the slicer circuit is coupled to an output node of the DCTS. The processor has an input node coupled to an output node of the slicer circuit. The DAC has an input node coupled to an output node of the processor and is configured to be coupled to a heater. The processor is configured to control (i) the DCTS to reduce a DC component of a signal on the output node of the DCTS and (ii) an output voltage on the output node of the DAC, both based on a signal output by the slicer circuit.

Examples described herein generally relate to a temperature-locked loop for optical elements. In an example, a device includes a controller and a digital-to-analog converter (DAC). The controller includes a DC-controllable transimpedance stage (DCTS), a slicer circuit, and a processor. The DCTS is configured to be coupled to a photodiode. An input node of the slicer circuit is coupled to an output node of the DCTS. The processor has an input node coupled to an output node of the slicer circuit. The DAC has an input node coupled to an output node of the processor and is configured to be coupled to a heater. The processor is configured to control (i) the DCTS to reduce a DC component of a signal on the output node of the DCTS and (ii) an output voltage on the output node of the DAC, both based on a signal output by the slicer circuit.

Apparatus and methods for control and calibration of external oscillators are provided herein. In certain embodiments, an electronic oscillator system includes a semiconductor die and a controllable oscillator that is external to the semiconductor die. The oscillation frequency of the controllable oscillator is tuned by a first varactor and a second varactor. The semiconductor die includes a phase-locked loop (PLL) that provides fine tuning to the controllable oscillator by controlling the first varactor, and a calibration circuit that provides coarse tuning to the controllable oscillator by controlling the second varactor.

Apparatus and methods for control and calibration of external oscillators are provided herein. In certain embodiments, an electronic oscillator system includes a semiconductor die and a controllable oscillator that is external to the semiconductor die. The oscillation frequency of the controllable oscillator is tuned by a first varactor and a second varactor. The semiconductor die includes a phase-locked loop (PLL) that provides fine tuning to the controllable oscillator by controlling the first varactor, and a calibration circuit that provides coarse tuning to the controllable oscillator by controlling the second varactor.

A signal transmission device includes a first pulse transmitting circuit configured to generate a first transmission pulse signal in synchronization with one of a rising edge and a falling edge of a first reference clock signal, a first pulse receiving circuit configured to receive a first reception pulse signal and generate a second reference clock signal, a first insulation communication circuit configured to transmit the first transmission pulse signal as the first reception pulse signal while insulating between the first pulse transmitting circuit and the first pulse receiving circuit, and a drive clock signal generating circuit configured to generate a drive clock signal having a predetermined oscillation frequency and a predetermined duty or a predetermined pulse width in synchronization with the second reference clock signal.

A signal transmission device includes a first pulse transmitting circuit configured to generate a first transmission pulse signal in synchronization with one of a rising edge and a falling edge of a first reference clock signal, a first pulse receiving circuit configured to receive a first reception pulse signal and generate a second reference clock signal, a first insulation communication circuit configured to transmit the first transmission pulse signal as the first reception pulse signal while insulating between the first pulse transmitting circuit and the first pulse receiving circuit, and a drive clock signal generating circuit configured to generate a drive clock signal having a predetermined oscillation frequency and a predetermined duty or a predetermined pulse width in synchronization with the second reference clock signal.

An apparatus includes a digitally controlled oscillator (DCO), which includes an inductor coupled in series with a first capacitor. The DCO further includes a second capacitor coupled in parallel with the series-coupled inductor and first capacitor, a first inverter coupled in parallel with the second capacitor, and a second inverter coupled back-to-back to the first inverter. The DCO further includes a digital-to-analog-converter (DAC) to vary a capacitance of the first capacitor.

An apparatus includes a digitally controlled oscillator (DCO), which includes an inductor coupled in series with a first capacitor. The DCO further includes a second capacitor coupled in parallel with the series-coupled inductor and first capacitor, a first inverter coupled in parallel with the second capacitor, and a second inverter coupled back-to-back to the first inverter. The DCO further includes a digital-to-analog-converter (DAC) to vary a capacitance of the first capacitor.

The invention relates to a device for synchronizing a periodic high frequency power signal (18) and an external reference signal (10). The device comprises a phase control circuit (100) and a digital oscillator circuit (130). The digital oscillator circuit (130) is connected to the phase control circuit (100). The digital oscillator circuit (130) comprises means for generating the periodic high frequency power signal (18) dependent on the control signal from the phase control circuit. The phase control circuit (100) is configured to determine a phase difference of the periodic high frequency power signal (18) and the external reference signal (10).

The invention relates to a device for synchronizing a periodic high frequency power signal (18) and an external reference signal (10). The device comprises a phase control circuit (100) and a digital oscillator circuit (130). The digital oscillator circuit (130) is connected to the phase control circuit (100). The digital oscillator circuit (130) comprises means for generating the periodic high frequency power signal (18) dependent on the control signal from the phase control circuit. The phase control circuit (100) is configured to determine a phase difference of the periodic high frequency power signal (18) and the external reference signal (10).