Abstract: An accelerometer is provided which is suitably rugged for use in on-board automotive safety control and navigational systems. The preferred thick film accelerometer is formed from an alumina substrate having an integrally formed U-shaped flexure member which surrounds an intermediate support member. A mass is provided on the unsupported end of the U-shaped flexure member. Deflection is maximum at the unsupported end of the U-shaped flexure member, while strain is maximum at the supported end of the flexure member. Four piezoresistors for detecting the strain within the flexure member corresponding to the acceleration in the direction perpendicular to the plane of the support member are provided on the U-shaped flexure member adjacent its supported ends. The four piezoresistors form a Wheatstone bridge, whose analog output voltage is conditioned and amplified to provide the output signal. The signal conditioning and amplifying circuitry are preferably located on the support member.

Abstract: Disclosed is a wirebond pin having a star-shaped anchor, collar and paddle. The collar prevents passivation material, used to make a sealed semiconductor device, from leaking out of the package. The collar also helps to eliminate the resonant vibration of the pin during ultrasonic wirebonding at the paddle.

Abstract: A microaccelerometer package is provided for use in on-board automotive safety control and navigational systems. The microaccelerometer package is constructed so as to minimize the influence of extraneous mechanical stress and vibrational resonance on the micromachined accelerometer. The microaccelerometer package includes a rigid housing in which there is a cavity for receiving the micromachined accelerometer unit and the signal-processing circuitry. The lower surface of the cavity is interrupted by a recess projecting below the plane of the lower surface. The micromachined accelerometer unit is secured within the recess so as to be below the plane of the lower surface. The signal-processing circuitry is supported by a substrate which is secured to the lower surface of the cavity.

Abstract: Compositions useful for printing controllable adhesion conductive patterns on a printed circuit board include finely divided copper powder, a screening agent and a binder. The binder is designed to provide controllable adhesion of the copper layer formed after sintering to the substrate so that the layer can lift off the substrate in response to thermal stress. Additionally, the binder serves to promote good cohesion between the copper particles to provide good mechanical strength to the copper layer so that it can tolerate lift off without fracture.

Abstract: A technique for providing controlled adhesion of a portion of a printed conductor to a circuit board employs an inhibitor layer between the circuit board and the portion of the printed conductor where such controlled adhesion is desired. The inhibitor layer is formed using a mixture of finely divided alumina powder and a glass frit, which are both suspended in an organic screening agent. An electrical module connected between controllably adherent conductor portions is thereby able to move to relative mechanical stresses.

Abstract: Compositions useful for printing controllable adhesion conductive patterns on a printed circuit board include finely divided copper powder, a screening agent and a binder. The binder is designed to provide controllable adhesion of the copper layer formed after sintering to the substrate so that the layer can lift off the substrate in response to thermal stress. Additionally, the binder serves to promote good cohesion between the copper particles to provide good mechanical strength to the copper layer so that it can tolerate lift off without fracture.

Abstract: A printed circuit board assembly uses a conductive pattern that includes both firmly adherent conductors and controllably adherent conductors. The controllably adhering conductors are free to lift off the printed circuit board to relieve mechanical forces caused by thermal stresses at solder joints between the controllably adherent conductors and integrated circuit chips of the assembly.