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:
Aug. 07, 2018
Filed:
Dec. 15, 2017
Hitachi Metals, Ltd., Minato-ku, Tokyo, JP;
Alexei V. Smirnov, Fort Collins, CO (US);
Patrick Albright, Wellington, CO (US);
HITACHI METALS, LTD., Tokyo, JP;
Abstract
Mass flow controllers with on-tool diagnostic capabilities and methods for on-tool diagnostics are disclosed. A mass flow controller includes a differential voltage processing component to provide a first output that is indicative of a differential voltage between second and fourth nodes of a bridge circuit and a top voltage processing component provides a second output indicative of a top voltage between the first node and the third node of the bridge circuit. Top-and-differential voltage reference data stored in non-volatile memory defines a characteristic curve relating top voltage reference values to corresponding differential voltage reference values. A sensor analysis component obtains a top and differential voltage pair and assesses whether the top and differential voltage pair deviates from the characteristic curve to determine whether the sensing element circuit has changed since the top-and-differential voltage reference data was stored in the non-volatile memory.