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A MEMS based pressure sensor for flow measurements includes a pressure sense die located between a media seal and a conductive seal. Such a system includes a pressure sense die located between a media seal and a conductive seal. A sensing diaphragm is generally associated with the pressure sense di

A MEMS based pressure sensor for flow measurements includes a pressure sense die located between a media seal and a conductive seal. Such a system includes a pressure sense die located between a media seal and a conductive seal. A sensing diaphragm is generally associated with the pressure sense die, wherein the sensing diaphragm deflects when a pressure is applied thereto. An impedance circuit is generally embedded with one or more resistors on the sensing diaphragm to which the pressure to be detected is applied. An ASIC is generally associated with the impedance circuit and the sense die, wherein the ASIC is placed on a lead frame for signal conditioning in order to detect a change in the pressure.

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What is claimed is: 1. A MEMS based pressure sensing system for flow rate measurements, comprising: a sensor partitioned into a first half and a second half, with a wall member separating said first half and said second half; a pressure block comprising a sensing diaphragm associated with a piezore

What is claimed is: 1. A MEMS based pressure sensing system for flow rate measurements, comprising: a sensor partitioned into a first half and a second half, with a wall member separating said first half and said second half; a pressure block comprising a sensing diaphragm associated with a piezoresistive material, wherein said sensing diaphragm deflects when a pressure is applied to said piezoresistive material; a first signal conditioning unit arranged in said first half of said sensor, wherein said first signal conditioning circuit comprises an impedance circuit embedded with at least one piezoresistive element associated with said piezoresistive material; and a second signal conditioning unit arranged in said second half of said sensor, wherein said second signal conditioning unit incorporates a signal amplifier, such that said first and second signal conditioning units, said pressure block, said sensing diaphragm and said sensor provide a MEMS based pressure sensing system for flow rate measurements. 2. The system of claim 1 wherein said signal amplifier comprises an ASIC. 3. The system of claim 1 further comprising: a conductive elastomeric pad positioned within said first half; a pressure sensor positioned on said conductive elastomeric pad; an elastomeric media seal positioned on said sensor; a flow through tube located on said elastomeric media seal, wherein said flow through tube is attached to a housing such that a flow through said flow tube and said housing together form a hermetic seal by snap fit, which prevents an escape or an entry of fluid through said hermetic seal, wherein said flow through said flow tube follows a path for admitting a fluid under pressure into said first half. 4. The system of claim 3 further comprising an electrical connector through said wall member thereby forming an electrical connection between said sensor and said signal amplifier. 5. The system of claim 3 further comprising a lead frame comprising a plurality of electrical connectors extending through said housing, wherein said lead frame forms an electrical connection with said sensor and said signal amplifier. 6. The system of claim 1 wherein said sensor comprises a piezoresistive pressure sensor. 7. The system of claim 1 wherein said impedance circuit comprises a four-resistor Wheatstone bridge fabricated on a single monolithic die utilizing micromachining technology. 8. The system of claim 1 wherein said first signal conditioning unit on excitation produces a signal output. 9. The system of claim 2 wherein said ASIC comprises: a programmable gain amplifier (PGA) for pre-amplifying a bridge sensor signal generated by a bridge sensor; a multiplexer (MUX) connected to said PGA, wherein said MUX transmits said bridge sensor signal from said bridge sensor; an analog-to-digital converter (ADC) connected to said MUX, wherein said ADC converts said bridge sensor signal from said MUX into at least one digital value; a calibration microcontroller (CMC) connected to said ADC, wherein said CMC provides a digital signal correction to said at least one digital value generated by said ADC; a ROM connected to said CMC, wherein said ROM stores a special correction formula; an EEPROM connected to said CMC, wherein said EEPROM calibrates correction equation coefficients; a digital-to-analog converter (DAC) for converting a final value output from said CMC into an analog voltage; and a serial interface (SIF) connected to said EEPROM, wherein said SIF provides an output signal. 10. The system of claim 9 wherein said SIF programs configuration data and correction parameters into said EEPROM. 11. A MEMS based pressure sensing system for flow rate measurements, comprising: a sensor partitioned into a first half and a second half, with a wall member separating said first half and said second half, wherein said sensor comprises a piezoresistive pressure sensor; a pressure block comprising a sensing diaphragm associated with a piezoresistive material, wherein said sensing diaphragm deflects when a pressure is applied to said piezoresistive material; a first signal conditioning unit arranged in said first half of said sensor, wherein said first signal conditioning circuit comprises an impedance circuit embedded with at least one piezoresistive element associated with said piezoresistive material; and a second signal conditioning unit arranged in said second half of said sensor, wherein said second signal conditioning unit incorporates a signal amplifier, wherein said signal amplifier comprises an ASIC, such that said first and second signal conditioning units, said pressure block, said sensing diaphragm and said sensor provide a MEMS based pressure sensing system for flow rate measurements. 12. The system of claim 11 further comprising: a conductive elastomeric pad positioned within said first half; a pressure sensor positioned on said conductive elastomeric pad; an elastomeric media seal positioned on said sensor; a flow through tube located on said elastomeric media seal, wherein said flow through tube is attached to a housing such that a flow through said flow tube and said housing together form a hermetic seal by snap fit, which prevents an escape or an entry of fluid through said hermetic seal, wherein said flow through said flow tube follows a path for admitting a fluid under pressure into said first half. 13. The system of claim 12 further comprising an electrical connector through said wall member thereby forming an electrical connection between said sensor and said signal amplifier. 14. The system of claim 12 further comprising a lead frame comprising a plurality of electrical connectors extending through said housing, wherein said lead frame forms an electrical connection with said sensor and said signal amplifier. 15. The system of claim 11 wherein said impedance circuit comprises a four-resistor Wheatstone bridge fabricated on a single monolithic die utilizing micromachining technology. 16. The system of claim 11 wherein said first signal conditioning unit on excitation produces a signal output. 17. The system of claim 11 wherein said ASIC comprises: a programmable gain amplifier (PGA) for pre-amplifying a bridge sensor signal generated by a bridge sensor; a multiplexer (MUX) connected to said PGA, wherein said MUX transmits said bridge sensor signal from said bridge sensor; an analog-to-digital converter (ADC) connected to said MUX, wherein said ADC converts said bridge sensor signal from said MUX into at least one digital value; a calibration microcontroller (CMC) connected to said ADC, wherein said CMC provides a digital signal correction to said at least one digital value generated by said ADC; a ROM connected to said CMC, wherein said ROM stores a special correction formula; an EEPROM connected to said CMC, wherein said EEPROM calibrates correction equation coefficients; a digital-to-analog converter (DAC) for converting a final value output from said CMC into an analog voltage; and a serial interface (SIF) connected to said EEPROM, wherein said SIF provides an output signal. 18. The system of claim 17 wherein said SIF programs configuration data and correction parameters into said EEPROM. 19. A MEMS based pressure sensing system for flow rate measurements, comprising: a sensor partitioned into a first half and a second half, with a wall member separating said first half and said second half; a pressure block comprising a sensing diaphragm associated with a piezoresistive material, wherein said sensing diaphragm deflects when a pressure is applied to said piezoresistive material; a first signal conditioning unit arranged in said first half of said sensor, wherein said first signal conditioning circuit comprises an impedance circuit embedded with at least one piezoresistive element associated with said piezoresistive material, wherein said impedance circuit comprises a four-resistor Wheatstone bridge fabricated on a single monolithic die utilizing micromachining technology, such that said first signal conditioning unit on excitation produces a signal output; and a second signal conditioning unit arranged in said second half of said sensor, wherein said second signal conditioning unit incorporates a signal amplifier, such that said first and second signal conditioning units, said pressure block, said sensing diaphragm and said sensor provide a MEMS based pressure sensing system for flow rate measurements. 20. The system of claim 19 further comprising: a conductive elastomeric pad positioned within said first half; a pressure sensor positioned on said conductive elastomeric pad; an elastomeric media seal positioned on said sensor; a flow through tube located on said elastomeric media seal, wherein said flow through tube is attached to a housing such that a flow through said flow tube and said housing together form a hermetic seal by snap fit, which prevents an escape or an entry of fluid through said hermetic seal, wherein said flow through said flow tube follows a path for admitting a fluid under pressure into said first half; an electrical connector through said wall member thereby forming an electrical connection between said sensor and said signal amplifier; and a lead frame comprising a plurality of electrical connectors extending through said housing, wherein said lead frame forms an electrical connection with said sensor and said signal amplifier.