Time-To-Digital Conversion unit, Circuit Device, Physical Quantity Measurement Apparatus, Electronic Instrument, And Vehicle

Abstract

The invention provides a time-to-digital conversion unit, a circuit device, a physical quantity measurement apparatus, an electronic instrument, and a vehicle, being able to realize high performance of the time-to-digital conversion circuit. The time-to-digital conversion circuit includes a first oscillation circuit that starts oscillating at the transition timing of a first signal and generates afirst clock signal having a first clock frequency, a second oscillation circuit that starts oscillating at the transition timing of a second signal and generates a second clock signal having a secondclock frequency, a first adjustment circuit that adjusts the oscillation frequency of the first oscillation circuit based on a reference clock signal, a second adjustment circuit that adjusts the oscillation frequency of the second oscillation circuit based on the reference clock signal, and a processing circuit that converts the time difference between the transition timing of the first signal and the transition timing of the second signal into a digital value based on the first and second clock signals.

Description

technical field [0001] The present invention relates to a time-to-digital conversion circuit, a circuit device, a physical quantity measuring device, electronic equipment, a mobile body, and the like. Background technique [0002] Conventionally, a time-to-digital conversion circuit for converting time into a digital value is known. As a conventional example of a time-to-digital conversion circuit that measures a time difference between a first signal and a second signal generated at an arbitrary timing, for example, a prior art disclosed in Patent Document 1 is known. [0003] Patent Document 1 discloses a timer circuit that includes: a first oscillator that starts oscillating at a frequency f in conjunction with generation of a start signal; and a second oscillator that in conjunction with generation of a stop signal Oscillation is started at frequency f+Δf, and the timing circuit compares the phase between the clock signal from the first oscillator and the clock signal f...

AI Technical Summary

Problems solved by technology

Therefore, the characteristics of the clock signal of the oscillator (such as temperature characteristics, process variation, jitter characteristics, etc.) may affect the timing accuracy, so that sufficient timing accuracy cannot be obtained

As an oscillator with good oscillation characteristics, for example, a crystal oscillator is considered, but it is difficult to control the startup of the crystal oscillator, so it is difficult to start oscillation at the transition timing of the first signal (or the second signal)

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