Patent ID: 7540193

Claim:
A triaxial acceleration sensor module in which a triaxial acceleration sensor is packaged in a housing, the sensor module comprising: a hollow housing provided with a partition plate, the partition plate having a through-hole and having a lower surface; a triaxial acceleration sensor provided inside the housing, the triaxial acceleration sensor comprising: a frame having an inner peripheral surface defining an opening and an outer peripheral surface; a weight member provided inside the opening of the frame in a spaced-apart relationship with respect to the inner peripheral surface of the frame by a predetermined interval; a weight member supporting portion for supporting the weight member in a freely suspended manner within the opening of the frame; and a plurality of flexible beams provided to interconnect the frame and the weight member supporting portion, each of the flexible beams having piezo resistance elements thereon; and a sensor driving IC for detecting changes in resistance values of the piezo resistance elements when acceleration in a predetermined direction is applied to the triaxial acceleration sensor and thereby the weight member oscillates in the corresponding direction so that some of the piezo resistance elements are elastically deformed, the sensor driving IC having an upper surface, wherein the through-hole has a size so that the triaxial acceleration sensor is received through a predetermined gap between the outer peripheral surface of the frame and an inner peripheral of the partition plate defining the through-hole, and wherein the triaxial acceleration sensor is directly bonded to the upper surface of the sensor driving IC via the through-hole and the sensor driving IC is bonded to the lower surface of the partition plate of the housing.