| 摘要 |
A combined wet-wet differential transducer and a gage pressure transducer are located in the same housing. A semiconductor chip which is formed from a single substrate, has located thereon an absolute or gage sensor chip on one section and a delta or differential sensor chip on a second section. Each sensor chip has a Wheatstone bridge arrangement comprising piezoresistors and responsive to an applied pressure. The absolute or gage chip, as well as the differential or delta chip are placed in a header having a front section and a back section. Each section has an outer surface with a central section joining the front and back sections to form an H shaped header. The front section outer surface has a depression of a given area with a first flexible isolation diaphragm covering the depression. The back section outer surface has a second depression of a given area with a second flexible isolation diaphragm covering the second depression, where the first and second diaphragms are relatively of the same size and area. A channel positioned within the central area and extending and communicating with the first and second depressions. The header described above, has a first sensor chip indicative of an absolute or gage sensor and a second sensor chip indicative of a differential sensor. Both sensors, as indicated, receive a first pressure at a corresponding diaphragm surface. The housing which contains the above noted header has a tube which communicates with the bottom diaphragm side of the differential chip section. The top side of the both the differential chip section and the absolute chip section receives the same pressure via a pressure port in the header. The differential portion of the chip receives a pressure via a curved tube which is directed to the second isolation diaphragm and which pressure propagates from the diaphragm through the channel and therefore applies that pressure to the underside of the differential sensor section.
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