TRANSDUCER PACKAGING ASSEMBLY FOR USE IN SENSING UNIT SUBJECTED TO HIGH G FORCES

摘要

A transducer packaging assembly for use in a sensing unit subjected to high forces of acceleration includes a base having a cavity. A pressure sensitive semiconductor die is bonded to a large backplate having a shape so that it nestles into the cavity but is spaced from a surface of the cavity. A planar cover secured to the base has a hole larger than the die but smaller than the backplate, and thin wires extend from the die to electrical connections on the assembly. A viscous fluid fills a space between the backplate and the cavity, and a space between the backplate and the cover, and transmits a pressure to be measured to the pressure sensitive die. The viscous fluid has a sufficiently high viscosity to oppose movement of the backplate relative to the cavity while cushioning the pressure sensitive die and the backplate from forces of acceleration.