A frequency reference generator includes (i) an integrated frequency source having drive circuitry that drives a resonant (e.g., non-trimmable LC) tank to generate an oscillator signal, (ii) at least one temperature sensor that generates at least one measured temperature signal, and (iii) a frequency-adjustment circuit that adjusts the oscillator signal frequency to generate the frequency reference based on the measured temperature signal and a (e.g., sample-specific) mapping from temperature to a corresponding frequency-adjustment parameter (e.g., a divisor value for a fractional frequency divider). In some embodiments, a Colpitts oscillator generates the oscillator signal based on the measured temperature signal, where the Colpitts oscillator has voltage/temperature-compensation circuitry that compensates for variations in power supply voltage and operating temperature. Such frequency reference generators achieve substantial PVT insensitivity with as little as a single 1T-trim or even no trim at all.

A synchronous oscillation circuit has multiple oscillators, a grounding unit and a common floating grounding unit. Each of the oscillators has a ground terminal. The grounding unit has a first terminal and a second terminal, wherein the second terminal is grounded. The common floating grounding unit is electrically connected between the ground terminals of the oscillators and the first terminal of the grounding unit. The oscillators are grounded through the common floating grounding unit and the grounding unit, so that the oscillators interfere with each other. When the oscillation signals generated by the oscillators reach a steady state, the oscillation frequencies of the oscillators are synchronized.

An integrated circuit device includes a substrate, a joining part provided on the substrate and joined to a vibrator, and a plurality of bonding pads provided on the substrate. The joining part includes an insulating protective film that covers a part of a surface of the substrate, and no insulating protective film is provided between the adjacent bonding pads.

A temperature compensated oscillator includes a resonator element, an oscillation circuit, and a temperature compensation circuit. Assuming an observation time as T, an MTIE value at 0.1 s<1 s is 1.3 ns or less, an MTIE value at 1 s<10 s is 1.3 ns or less, an MTIE value at 10 s<100 s is 1.8 ns or less, an MTIE value at 100 s<1000 s is 2.9 ns or less, a TDEV value at 0.1 s<10 s is 47 ps or less, a TDEV value at 10 s<100 s is 65 ps or less, and a TDEV value at 100 s<1000 s is 94 ps or less.

A synchronous oscillation circuit has multiple oscillators, a grounding unit and a common floating grounding unit. Each of the oscillators has a ground terminal. The grounding unit has a first terminal and a second terminal, wherein the second terminal is grounded. The common floating grounding unit is electrically connected between the ground terminals of the oscillators and the first terminal of the grounding unit. The oscillators are grounded through the common floating grounding unit and the grounding unit, so that the oscillators interfere with each other. When the oscillation signals generated by the oscillators reach a steady state, the oscillation frequencies of the oscillators are synchronized.

An integrated circuit device includes a substrate, a joining part provided on the substrate and joined to a vibrator, and a plurality of bonding pads provided on the substrate. The joining part includes an insulating protective film that covers a part of a surface of the substrate, and no insulating protective film is provided between the adjacent bonding pads.