Abstract: A frequency-adjustable oscillator suitable for digital signal clock synchronization comprises a crystal oscillator circuit for generating a driving signal and having a voltage-variable control input for adjusting a frequency of the driving signal, a phase detector circuit for generating a phase offset signal, a filter which operates on the phase offset signal to produce a VCO control signal, a voltage controlled oscillator circuit operably linked to the filter and responsive to the VCO control signal for generating an analog controlled-frequency signal, a frequency divider circuit for generating a reduced frequency feedback signal in response to the controlled-frequency signal. The frequency-adjustable oscillator also includes a double-sided package including a platform having a central portion and an outer portion with sidewalls extending substantially upwardly and substantially downwardly from the outer portion of the platform.

Abstract: A frequency-adjustable oscillator suitable for digital signal clock synchronization comprises a crystal oscillator circuit for generating a driving signal and having a voltage-variable control input for adjusting a frequency of the driving signal, a phase detector circuit for generating a phase offset signal, a filter which operates on the phase offset signal to produce a VCO control signal, a voltage controlled oscillator circuit operably linked to the filter and responsive to the VCO control signal for generating an analog controlled-frequency signal, a frequency divider circuit for generating a reduced frequency feedback signal in response to the controlled-frequency signal. The frequency-adjustable oscillator also includes a double-sided package including a platform having a central portion and an outer portion with sidewalls extending substantially upwardly and substantially downwardly from the outer portion of the platform.

Abstract: A dual-cavity temperature compensated crystal oscillator (100) provides a three-layer ceramic package (110), with a crystal (170) sealed in a well or cavity (148). Oscillator components (180-184) such as a compensation circuit and an oscillator are attached through screened solder onto the back side of the ceramic package (110) and are encapsulated within potting compound or encapsulant. Electrical connection is provided between the oscillator and compensation circuitry and the piezoelectric element (170) to produce a frequency-controlled oscillator. After frequency tuning, a hermetic seal is provided between a cover (160) and ledge (140) to hermetically seal the cavity (148).

Abstract: A dual-cavity temperature compensated crystal oscillator (100) provides a three-layer ceramic package (110), with a crystal (170) sealed in a well or cavity (148). Oscillator components (180-184) such as a compensation circuit and an oscillator are attached through screened solder onto the back side of the ceramic package (110) and are encapsulated within potting compound or encapsulant. Electrical connection is provided between the oscillator and compensation circuitry and the piezoelectric element (170) to produce a frequency-controlled oscillator. After frequency tuning, a hermetic seal is provided between a cover (160) and ledge (140) to hermetically seal the cavity (148).

Abstract: A surface mount crystal package (10) receptacle mounting adapted to canti-leverably receive a piezoelectric element. The surface mount crystal package (10) is configured to hermetically enclose a crystal resonator (19) or crystal filter mounted in a proximal base (12) in a cantilever fashion. This package (10) is hermetically sealed in the proximal base 12, a distal cap (14) and sleeve (16). The package (10) is adapted to improve and faciliate surface mounting, provide a low cost and automatable assembly, and provide a low-stress mounting of a piezoelectric element in a simplified and portable design.

Abstract: A surface mountable piezoelectric device that includes an in situ finish plate mask is mounted on a substrate (20) that includes feedthrough holes (26, 28, and 30) to conduct signals from a piezoelectric element (40) that may include multiple resonator stages (48, 46, 50, and 56). A metallic support structure that includes windows or holes therethrough (72, 74 and 76) permits tuning of the piezoelectric device by mass loading during manufacturing, compliantly supports the piezoelectric element (40), provides RF shielding for the resonators, and is an in situ finish plate mask.

Abstract: A crystal holder is provided which is capable of supporting any one of a plurality of piezoelectric crystals having different preselected diameters. The crystal holder includes two side portions, each portion having a stair step-like structure, the stair steps of one side portion leading upwardly and away from the stair steps of the remaining side portion. Each step of one side portion is respectively horizontally aligned with a corresponding step of the remaining side portion such that each step pair thus formed has a different distance therebetween and is thus capable of accepting for mounting one of a plurality of piezoelectric crystals having preselected diameters corresponding to the distances between the steps of the step pairs.