A phase look loop (PLL) device has a dynamic lock range that is based on a temperature measured during a calibration process. The PLL device includes a calibration circuit configured to receive a temperature reading corresponding to a junction temperature of the PLL device during the calibration process. Based on this temperature reading, the calibration circuit initiates a preset procedure that presets a control voltage of a voltage control oscillator in the PLL device. The preset procedure implements a calibration function defined by a slope with a numerator component and a denominator component. The numerator component corresponds to a range of the control voltage, whereas the denominator component corresponds to a range of ambient temperatures within which the PLL device operates.

A circuit device includes a processor adapted to perform a signal processing of temperature compensation of an oscillation frequency based on temperature detection data from an external temperature sensor disposed outside the circuit device to output frequency control data, and an oscillation signal generation circuit adapted to generate an oscillation signal with the oscillation frequency corresponding to the frequency control data using the frequency control data and a resonator disposed in a thermostatic oven.

An electronic apparatus includes a voltage-controlled oscillator and a biasing circuit. The voltage-controlled oscillator includes varactors. The voltage-controlled oscillator is configured to output an oscillating frequency at a first temperature. The biasing circuit electrically coupled with the varactors is configured to provide a first biasing voltage to the varactors at the first temperature, and provide a second biasing voltage to the varactors at a second temperature, in which the varactors have a first temperature coefficient, and the biasing circuit generates the first biasing voltage and the second biasing voltage according to values of the first temperature coefficient and a second temperature coefficient.

A current-to-voltage converter receives a current which varies with temperature according to a selected one of two or more temperature coefficient factors and converts it to a temperature-dependent voltage to be used as a control signal to a varactor in a voltage controlled oscillator, VCO, to compensate for temperature-induced frequency drift in the VCO. A feedback arrangement with hysteresis is provided for controlling the selection of the temperature coefficient factor and operates by comparing the temperature-dependent voltage with a reference voltage. The reference voltage may be pre-set and equivalent to a known operating temperature. A switching signal is generated when Vout approaches the reference voltage and in response, a control module generates a selection signal for selecting a different temperature coefficient factor. Thus, multi-slope voltage and current generation with a wide dynamic range is continuously provided, which is particularly useful for controlling VCO's used in short range FMCW radar systems.

An oscillation circuit includes a circuit for oscillation, a first frequency adjustment circuit for adjusting a frequency, and a first terminal. The oscillation circuit has a first mode in which the circuit for oscillation and the first frequency adjustment circuit are electrically connected to each other and the first frequency adjustment circuit and the first terminal are not electrically connected to each other, and a second mode in which the circuit for oscillation and the first frequency adjustment circuit operate and a terminal on a side where a signal of the first frequency adjustment circuit is output and the first terminal are electrically connected to each other.

A circuit device includes an A/D conversion unit, a processing unit that performs a temperature compensation process of an oscillation frequency based on temperature detection data and outputs frequency control data of the oscillation frequency, a D/A conversion unit, and an oscillation circuit. The D/A conversion unit (area DAC) is disposed on a first direction DR1 side of the A/D conversion unit (area ADC). When a direction crossing the first direction DR1 is defined as a second direction DR2, the processing unit (area DSPL) is disposed on the second direction DR2 side of the A/D conversion unit and the D/A conversion unit. When a direction opposite to the second direction DR2 is defined as a third direction DR3, the oscillation circuit (area OSC) is disposed on the third direction DR3 side or the first direction DR1 side of the D/A conversion unit.

Methods, systems, and computer products are presented herein for determining temperature using ultra-low power temperature sensing systems. An ultra-low power (ULP) temperature sensing system comprises a proportional to absolute temperature (PTAT) current source, a switched-capacitor converter electrically coupled to the PTAT current source, and a ULP analog-to-digital converter (ADC) electrically coupled to the PTAT current source and the switched-capacitor converter. The PTAT current source is configured to generate a PTAT current that varies with an operating temperature. The switched-capacitor converter is configured to generate an analog voltage signal based on the PTAT current. The ULP ADC is configured to output a digital voltage value corresponding to the analog voltage signal.

A phase look loop (PLL) device has a dynamic lock range that is based on a temperature measured during a calibration process. The PLL device includes a calibration circuit configured to receive a temperature reading corresponding to a junction temperature of the PLL device during the calibration process. Based on this temperature reading, the calibration circuit initiates a preset procedure that presets a control voltage of a voltage control oscillator in the PLL device. The preset procedure implements a calibration function defined by a slope with a numerator component and a denominator component. The numerator component corresponds to a range of the control voltage, whereas the denominator component corresponds to a range of ambient temperatures within which the PLL device operates.

A semiconductor device includes: a semiconductor element configured to output a compensation voltage; a constant current circuit configured to output a constant current so as to compensate for temperature dependence according to the comparison of the compensation voltage and a reference voltage; an oscillation circuit configured to output an oscillation signal according to the constant current; a check voltage generation circuit configured to output a check voltage; and a signal generation circuit configured to output a temperature information signal corresponding to the compensation voltage and the check voltage.