The disclosure provides an apparatus including: a pair of signal injection transistors each having a gate terminal coupled to a differential reference signal, and a pair of cross-coupled amplifier transistors configured to amplify a voltage of the differential reference signal to yield a voltage-amplified reference signal at a local oscillator (LO) port of a mixer; an electronic oscillator having an oscillation output node coupled to the LO port of the mixer in parallel with the injection-locked buffer, and configured to generate an oscillator output for transmission to the output node based on a back gate bias voltage applied to the electronic oscillator; and an access transistor having a gate coupled to a switching node, and a back gate terminal coupled to the back gate bias voltage, wherein the access transistor is configured to enable or disable current flow through the electronic oscillator in parallel with the injection-locked buffer.

A system includes a tunable bulk acoustic wave (BAW) resonator device and a direct-current (DC) tuning controller coupled to the tunable BAW resonator device. The system also includes an oscillator circuit coupled to the tunable BAW resonator device. The DC tuning controller selectively adjusts a DC tuning signal applied to the tunable BAW resonator device to adjust a signal frequency generated by the oscillator circuit.

An oscillator includes a substrate having a first substrate main surface and a substrate side surface, and a lid body bonded to the substrate and including a metal material, in which the substrate includes a substrate body having a first substrate body main surface corresponding to the first substrate main surface and a substrate body side surface corresponding to the substrate side surface, and provided with a cutout portion in the substrate body side surface, a side surface wiring provided along the cutout portion, a filling member provided in the cutout portion, and an insulating coating member provided on the first substrate body main surface.

An oscillator includes a substrate having a first substrate main surface and a substrate side surface, and a lid body bonded to the substrate and including a metal material, in which the substrate includes a substrate body having a first substrate body main surface corresponding to the first substrate main surface and a substrate body side surface corresponding to the substrate side surface, and provided with a cutout portion in the substrate body side surface, a side surface wiring provided along the cutout portion, a filling member provided in the cutout portion, and an insulating coating member provided on the first substrate body main surface.

The disclosure provides an apparatus including: a pair of signal injection transistors each having a gate terminal coupled to a differential reference signal, and a pair of cross-coupled amplifier transistors configured to amplify a voltage of the differential reference signal to yield a voltage-amplified reference signal at a local oscillator (LO) port of a mixer; an electronic oscillator having an oscillation output node coupled to the LO port of the mixer in parallel with the injection-locked buffer, and configured to generate an oscillator output for transmission to the output node based on a back gate bias voltage applied to the electronic oscillator; and an access transistor having a gate coupled to a switching node, and a back gate terminal coupled to the back gate bias voltage, wherein the access transistor is configured to enable or disable current flow through the electronic oscillator in parallel with the injection-locked buffer.

A system includes a tunable bulk acoustic wave (BAW) resonator device and a direct-current (DC) tuning controller coupled to the tunable BAW resonator device. The system also includes an oscillator circuit coupled to the tunable BAW resonator device. The DC tuning controller selectively adjusts a DC tuning signal applied to the tunable BAW resonator device to adjust a signal frequency generated by the oscillator circuit.

A resonator element includes an SC-cut quartz crystal substrate having a thickness t, and an excitation electrode disposed on a principal surface of the quartz crystal substrate, the principal surface being square or rectangular in shape, a side of which has a length L, 28L/t60 is satisfied.

A crystal oscillator includes an oscillating substrate, a hollow frame, a first electrode, and a second electrode. The oscillating substrate includes a main oscillating region and a thinned region that has a thickness smaller than that of the main oscillating region. The first and second electrodes are disposed on a first surface of the oscillating substrate and a second surface opposite to the first surface, respectively. The hollow frame is disposed on the second surface. The second electrode includes a second electrode portion that has at least one opening in positional correspondence with the thinned region. A method for making the crystal oscillator is also provided herein.

A rectangular quartz crystal blank having long sides substantially parallel to a Z axis of the quartz crystal blank, and short sides substantially parallel to an X axis of the quartz crystal blank. The quartz crystal blank includes a center region, a second region and a third region that are adjacent to the center region along a long-side direction, and a fourth region and a fifth region that are adjacent to the first region along a short-side direction. A thickness of the second region and a thickness of the third region are smaller than a thickness of the first region, and/or a thickness of the fourth region and a thickness of the fifth region are smaller than a thickness of the first region, and 20.78W/T22.10, where W is a length of a short side and T is a thickness.

A vibrator device includes a base; and a vibrator element including a quartz crystal vibrator element attached to the base via a first metal bump, in which the first metal bump is disposed on a straight line inclined within a range of +55 to +65 or 65 to 55 with respect to an X axis of the quartz crystal constituting the quartz crystal vibrator element in plan view seen from a direction in which the base and the quartz crystal vibrator element are arranged.