US Patent 7228745 Pressure sensor

A pressure sensor includes a hollow cylindrical stem, a sensor chip, and a wiring board. The hollow cylindrical stem has a pressure-sensitive flexible diaphragm at a first axial end thereof and an opening at a second axial end thereof, the opening for transmitting pressure into the stem. The sensor chip is provided on the diaphragm for outputting an electrical signal in proportion to the deformation of the diaphragm. The wiring board electrically connects the sensor chip to an external circuit. The wiring board is located around the sensor chip on the first axial end of the stem.