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:
Nov. 28, 2000
Filed:
Dec. 17, 1998
Keiji Narusawa, Kanagawa, JP;
Norio Shoji, Kanagawa, JP;
Sony Corporation, Tokyo, JP;
Abstract
An amplification circuit for an MR head which can realize a reduction of the power consumption, simplification of the circuit configuration by providing capacitors inside the circuit, and reduction of the number of externally provided parts, wherein a current is supplied to an MR head resistor from a bias current source and the amount of change of the head resistance is converted to a voltage change when reproducing magnetically recorded data. A direct current component of the voltage dropped in the head resistor is cut by capacitors, and only the alternating current component is input to a differential amplification circuit configured by transistors. Recorded data can be distinguished in accordance with an amplified output voltage, so capacitances of direct current cut-off capacitors can be set small and thus the direct current cut-off capacitors can be provided in the IC chip and the number of external parts can be reduced. Furthermore, since the base bias voltages of the transistors are set independently from the MR head, the power consumption can be reduced.