The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 02, 1986
Filed:
Dec. 05, 1984
Richard S Muller, Kensington, CA (US);
Dennis L Polla, Berkeley, CA (US);
The Regents of the University of California, Berkeley, CA (US);
Abstract
An integrated circuit pyroelectric sensor includes two MOSFETS coupled in a differential amplifier configuration, each MOSFET having a common source. A pyroelectric capacitor is coupled to the gate of a respective one of the MOSFET. A polysilicon filament is disposed between the pyroelectric capacitors which acts as a heating element when a current is passed therethrough. The voltage difference between the drain of each MOSFET is thus a function of the voltage difference between the pyroelectric capacitors. One of the pyroelectric capacitors is disposed at the leading edge of the sensor with respect to the direction of a fluid flow. The fluid flow across the sensor will cause the first capacitor to have a different temperature than the other capacitor of the trailing edge of the sensor whose temperature is a function of the temperature of the heating element. As the temperature of each pyroelectric capacitor changes, the amount of charge stored by each pyroelectric capacitor changes, thereby developing a differential voltage across the gates, and hence, the drains, of the integrated MOSFETS. Since the charge stored and voltage across each pyroelectric capacitor is a function of temperature, the differential voltage between the drains of each MOSFET is a function of temperature.