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:
May. 14, 2002
Filed:
Apr. 13, 2000
Sumitomo Electric Industries, Ltd., Osaka, JP;
Abstract
A modulation current at a predetermined frequency f is applied from an AC source to a flux locked loop for maintaining magnetic flux supplied to a SQUID at a constant value. An output voltage is picked out from the SQUID in this state to which a predetermined bias current is being applied from a current and field bias application circuit, and the picked out voltage passed through a filter and a rectifier is monitored by a voltage monitor. The filter picks out a frequency component of 80 kHz which is twice as high as the frequency component f, 40 kHz, applied from the AC source, and maximizes it. In this way, a method and a device for easily adjusting magnetic field bias in a modulation drive circuit for a SQUID can be provided.