Pressure transducer with multiplexed frequency transmitter

The pressure transducer for precise and reliable pressure measurement is described. Its aim was to reach better pressure ranges with lower price. The ceramic diaphragm for pressure sensing is applied and a new principle of special ASIC with multiplexed frequency transmitter for conditioning of f/sub X/ and f/sub R/ frequencies controlled by C/sub X/ and C/sub R/ sensor capacitances is exploit. Good protection against the moist and dusty ambient air and surrounding electromagnetic parasitic fields is achieved. The new pressure transducer is typically prepared for paper industry, chemical industry, medicine appliances and pharmacy: designed to 0... 10 kPa up to 0... 6 MPa pressure ranges, accuracy according to IEC 60770 0,5% FSO (BFSL: 0,25% FSO. Its ceramic sensor features high resistance against aggressive medias (e.g. acids and lye) due to its ceramic surface directly in contact with the media. The embedded microcontroller covers the IEEE 1451 functionality.