Microminiature ganged threshold accelerometers compatible with integrated circuit technology

Abstract

The device described permits threshold acceleration detection in a wide range from a few ten's of g's up to maybe 100 000 g's. It is a threshold sensing device with an extremely high on-to-off resistance ratio. The device consists of a flexible metal beam and an associated contact pad, which is activated by the force of the beam's inertial mass when being accelerated in a direction normal to the contact plane. The mechanical and electrical operation of the accelerometer is analyzed and expressions are given for the relationship between beam deflection, acceleration detection level, and various required beam dimensions. A batch fabrication procedure is demonstrated and acceleration test results up to 8000 g's are reported for multiple ganged accelerometers.