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. 22, 2003
Filed:
Oct. 29, 2001
Applicant:
Inventors:
Assignee:
Seiko Instruments Inc., , JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G01R 3/3035 ;
U.S. Cl.
CPC ...
G01R 3/3035 ;
Abstract
A signal detector has a SQUID, a bias current supply circuit for supplying a bias current to the SQUID, and a drive circuit for detecting a magnetic flux by receiving a voltage signal of the SQUID and reading out the input signal as an output voltage. The drive circuit has two systems including a flux-locked loop system for converting a voltage signal of the SQUID into a current signal and making a magnetic flux inside the SQUID constant by feeding back a signal whereto, and an output system separate from and operating independently of the flux-locked loop system for converting a voltage signal of the SQUID and reading out the converted voltage signal without feeding back a signal to the SQUID.