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:
Jul. 25, 2017
Filed:
Oct. 07, 2010
John Vandermey, Georgetown, CA;
John Vandermey, Georgetown, CA;
DH Technologies Development Pte. Ltd., Singapore, SG;
Abstract
An apparatus for measuring RF voltage from a quadrupole in a mass spectrometer are provided. The apparatus comprises at least one rectifying diode circuit for rectifying the RF voltage of the quadrupole to produce a rectified RF voltage. The apparatus further comprises at least one operational amplifier configured as a current to voltage converter, a negative input of the at least one operational amplifier connected to the output of at least one diode in the at least one rectifying diode circuit, a positive input of the at least one operational amplifier at ground, and an output of the at least one operational amplifier in a feedback loop with the negative input, to reduce reverse leakage current from the at least one diode.