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. 24, 1996
Filed:
Oct. 05, 1994
Johannes O Voorman, Eindhoven, NL;
Joao N Ramalho, Eindhoven, NL;
U.S. Philips Corporation, New York, NY (US);
Abstract
An arrangement for reading out an information signal from a magnetic record carrier. The arrangement includes a read head having a magneto-resistive element with a first terminal connected to a first point of constant potential, and a second terminal; a bias-current generator having an output for supplying a bias-current to the MR element and an amplifier circuit having a first terminal coupled to the output of the bias-current generator, and a second terminal coupled to the second terminal of the MR so as to form a series arrangement of the bias-current generator, the amplifier circuit and the MR element. At an output terminal of the amplifier circuit, the information signal is available. The amplifier circuit includes a MOS transistor connected between the output terminal and the second terminal; and a feedback circuit, including a resistor and a capacitor, having a low cut-off frequency which provides a bias voltage to the gate of the MOS transistor and forces the entire bias-current of the bias-current generator to flow through the MR element The arrangement is balanced with an additional MR element (optional), bias-current generator and amplifier circuit, which are substantially the same as the MR element, bias-current generator and amplifier circuit, respectively, with the cut-off capacitors of the two individual amplifiers being cross-coupled to reduce noise.