Y10T29/49133

Quartz crystal unit, quartz crystal oscillator and electronic apparatus
09553560 · 2017-01-24 · ·

In a quartz crystal unit, the unit comprising a case, a quartz crystal tuning fork resonator and a lid, the resonator having a tuning fork base, and first and second tuning fork tines, each of the first and second tuning fork tines having a first side surface and a second side surface opposite the first side surface, the first side surface of the first tuning fork tine confronting the second side surface of the second tuning fork tine; at least one groove having a plurality of surfaces including a first surface being formed in at least one of first and second main surfaces of each of the first and second tuning fork tines so that only the first surface of the at least one groove is directly opposite the first side surface of the corresponding tuning fork tine and a width of the at least one groove is greater than or equal to a distance in the width direction of the at least one groove measured from an outer edge of the at least one groove to an outer edge of the corresponding one of the first and second tuning fork tines and less than 0.07 mm.

Grid Arrays With Enhanced Fatigue Life
20170013725 · 2017-01-12 ·

Reliability is improved for the mechanical electrical connection formed between a grid array device, such as a pin grid array device (PGA) or a column grid array device (CGA), and a substrate such as a printed circuit board (PCB). Between adjacent PCB pads, a spacing pattern increases toward the periphery of the CGA, creating a misalignment between pads and columns. As part of the assembly method, columns align with the pads, resulting in column tilt that increases from the center to the periphery of the CGA. An advantage of this tilt is that it reduces the amount of contractions and expansions of columns during thermal cycling, thereby increasing the projected life of CGA. Another advantage of the method is that it reduces shear stress, further increasing the projected life of the CGA.

Panel-molded electronic assemblies

A method of encapsulating a panel of electronic components such as power converters reduces wasted printed circuit board area. The panel, which may include a plurality of components, may be cut into one or more individual pieces after encapsulation with the mold forming part of the finished product, e.g. providing heat sink fins or a surface mount solderable surface. Interconnection features provided along boundaries of individual circuits are exposed during the singulation process providing electrical connections to the components without wasting valuable PCB surface area. The molds may include various internal features such as registration features accurately locating the circuit board within the mold cavity, interlocking contours for structural integrity of the singulated module, contours to match component shapes and sizes enhancing heat removal from internal components and reducing the required volume of encapsulant, clearance channels providing safety agency spacing and setbacks for the interconnects. Wide cuts may be made in the molds after encapsulation reducing thermal stresses and reducing the thickness of material to be cut during subsequent singulation. External mold features can include various fin configurations for heat sinks, flat surfaces for surface mounting or soldering, etc. Blank mold panels may be machined to provide some or all of the above features in an on-demand manufacturing system. Connection adapters may be provided to use the modules in vertical or horizontal mounting positions in connector, through-hole, surface-mount solder variations. The interconnects may be plated to provide a connectorized module that may be inserted into a mating connector.

Panel-molded electronic assemblies

A method of encapsulating a panel of electronic components such as power converters reduces wasted printed circuit board area. The panel, which may include a plurality of components, may be cut into one or more individual pieces after encapsulation. The mold may be used to form part of the finished product, e.g. providing heat sink fins or a surface mount solderable surface. Interconnection features provided along boundaries of individual circuits are exposed during the singulation process providing electrical connections to the components without wasting valuable PCB surface area. The molds may include various internal features such as registration features accurately locating the circuit board within the mold cavity, interlocking contours for structural integrity of the singulated module, contours to match component shapes and sizes enhancing heat removal from internal components and reducing the required volume of encapsulant, clearance channels providing safety agency spacing and setbacks for the interconnects. Wide cuts may be made in the molds after encapsulation reducing thermal stresses and reducing the thickness of material to be cut during subsequent singulation. External mold features can include various fin configurations for heat sinks, flat surfaces for surface mounting or soldering, etc. Blank mold panels may be machined to provide some or all of the above features in an on-demand manufacturing system. Connection adapters may be provided to use the modules in vertical or horizontal mounting positions in connector, through-hole, surface-mount solder variations. The interconnects may be plated to provide a connectorized module that may be inserted into a mating connector. Reuseable plates may be used instead of the heat sink panels. Alternatively the panel may be encapsulated in and separated from a re-useable mold after curing.