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:
Jun. 25, 1996
Filed:
Feb. 03, 1994
Applicant:
Inventors:
Yoshimi Yamamoto, Naka-machi, JP;
Tomoyuki Tobita, Katsuta, JP;
Assignee:
Hitachi, Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G01L / ; H01C / ;
U.S. Cl.
CPC ...
73708 ; 73720 ; 73726 ; 338 42 ; 374198 ;
Abstract
A differential pressure transmitter having a differential pressure sensor, a temperature sensor and a static pressure sensor all provided on the semiconductor substrate of a single semiconductor chip. A reference resistor is provided in a part of the chip. Resistances of the differential pressure sensor and the reference resistor are compared periodically in order to determine the condition including service life of the differential pressure sensor.