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. 14, 2001
Filed:
Apr. 02, 1999
Tuan V. Ngo, Eden Prairie, MN (US);
John D. Leighton, Anoka, MN (US);
Agere Systems Guardian Corp., Orlando, FL (US);
Abstract
A read system for reading information from a storage medium and for providing an output signal to circuitry external from the read system is disclosed. The read system includes individual channel circuitry, a bias current generator for providing a bias current to the read system, and preamplifier circuitry connected between the bias current generator and the individual channel circuitry. The individual channel circuitry further includes a first and a second magnetoresistive element, a first and a second transistor, and a first and a second switch. The preamplifier circuit further includes a first and a second capacitor connected between a low potential and the first and second switches, respectively, and a third capacitor connected between the first and second capacitors. The preamplifier also includes a first and a second operational amplifier having an output connected to a base of the first transistor and a base of the second transistor. respectively, and a feedback unit connected to the bias current generator.