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. 19, 2017
Filed:
Apr. 08, 2015
Denso Corporation, Kariya, Aichi-pref., JP;
Masafumi Umeno, Okazaki, JP;
DENSO CORPORATION, Kariya, JP;
Abstract
A control circuit includes a sweep circuit for supplying a sweep current to a gas concentration sensor, a current detection resistor for detecting a sensor current flowing in the gas concentration sensor, a calculation circuit for calculating an impedance of the gas concentration sensor based on the sensor current and an inter-terminal voltage of the gas concentration sensor, and a protective element for suppressing external noise from being applied to the sweep circuit and the calculation circuit. The sweep current is divided to flow in a first protective element and the gas concentration sensor. The sensor current is divided to flow in a second protective element and the current detection resistor. The calculation circuit calculates a loss current flowing to the first protective element or a second loss current flowing to the second protective element and calculates the sensor current based on the calculated current.