Physical quantity measurement apparatus, electronic apparatus, and vehicle

A physical quantity measurement apparatus comprising:

• a first resonator;
• a second oscillator;
• and
• an integrated circuit device,
• wherein the integrated circuit device includes:
• a first oscillation circuit configured to cause the first resonator to oscillate and generate a first clock signal having a first clock frequency,
• a second oscillation circuit configured to cause the second oscillator to oscillate and generate a second clock signal having a second clock frequency, the second clock frequency being different from the first clock frequency, and
• a measurement unit having a time-to-digital conversion circuit configured to convert time into a digital value based on the first clock signal and the second clock signal,
• wherein the time-to-digital conversion circuit is configured to convert a time difference between transition timings of a first signal and a second signal into a digital value,
• wherein a measurement period is from a first phase synchronization timing to a second phase synchronization timing of the first clock signal and the second clock signal,
• wherein an inter-clock time difference is a time difference between transition timings of the first clock signal and the second clock signal, and
• wherein the time-to-digital conversion circuit is configured to:
• generate a plurality of the first signals in a plurality of clock cycles of the measurement period, and acquire a plurality of the second signals whose signal levels have been changed so as to correspond to the plurality of generated first signals, and
• obtain the digital value based on a comparison of the time difference of the first signal and the second signal in each of the plurality of clock cycles with the inter-clock time difference in each clock cycle.

A physical quantity measurement apparatus comprising:

• a first resonator;
• a second oscillator;
• and
• an integrated circuit device,
• wherein the integrated circuit device includes:
• a first oscillation circuit configured to cause the first resonator to oscillate and generate a first clock signal having a first clock frequency,
• a second oscillation circuit configured to cause the second oscillator to oscillate and generate a second clock signal having a second clock frequency, the second clock frequency being different from the first clock frequency, and
• a measurement unit having a time-to-digital conversion circuit configured to convert time into a digital value based on the first clock signal and the second clock signal,
• wherein a jitter amount of the first clock signal and the second clock signal per clock cycle is J,
• wherein a resolution in time-to-digital conversion is Δt,
• and wherein J≤Δt.