Abstract: A magnetoresistive effect sensor uses a shielded-type magnetoresistive effect element using a magnetoresistive effect film formed by a basic configuration of a combination of a free layer, a barrier layer formed on the free layer, and a fixed layer formed on the barrier layer, wherein a sensing current flows substantially perpendicular to the magnetoresistive effect film, and wherein an amorphous material or a microcrystalline material is used in a lower shield.

Abstract: A power supply apparatus comprises a variable frequency oscillating circuit, a driver, soft start circuit, switching elements for receiving a switching signal, a resonating capacitor connected at a connection point of the switching elements via a primary coil of a transformer, rectifying circuit provided at a secondary coil of the transformer, an amplifier for comparing an output voltage, Vb obtained at the rectifying circuit and a reference voltage, Vref, a photo-coupler for controlling an impedance of an oscillating element of a variable frequency oscillating circuit based on the comparison output and a charge voltage control circuit for controlling an oscillation frequency when the variable oscillation circuit is initially driven. A frequency control signal when power is ON is made nonlinear relevant to a time. As a result, a change in oscillation frequency immediately after power is ON is made gentle, and a rapid change in current that flows in a primary coil is eliminated.

Abstract: In a magnetoresistive effect composite head, magnetic shields oppose each other on a slider main body made of a ceramic material through a predetermined gap, and a magnetoresistive effect element is sandwiched and stacked between the magnetic shields with a magnetic spacer layer made of an insulator. A recording head portion uses one of the magnetic shields as a first magnetic pole, and has a second magnetic pole formed on a surface of the first magnetic pole opposite to the magnetoresistive effect element through a magnetic gap, to record information on a recording medium by means of a magnetic field generated in the magnetic gap. The magnetoresistive effect element includes a central region made of a spin-valve element to sense a medium field, and end regions for supplying a bias field and a current to the central region. The second magnetic pole is constituted by a stacked film of first and second magnetic films having different saturation magnetizations.

Abstract: An ID head is formed after a MR head is formed. An upper shield far from a substrate is a first magnetic pole. A nonmagnetic insulator existing through a magnetic gap on the first magnetic pole determines zero throat height, thereby specifying a recording track width of less than 2 .mu.m. The ID head comprises a front end portion of a second magnetic pole, which is exposed to ABS and partly rides over the nonmagnetic insulator, a nonmagnetic insulator for burying a step by the front end portion, a coil which is formed on the nonmagnetic insulator and covered with a nonmagnetic insulator, and a main body portion of the second magnetic pole formed so as to ride over the coil and front end portion. As a result, it is possible to solved various problems of the ID head in which the front end portion of the second magnetic pole is formed first to realize a narrow track width.

Abstract: A merged head device which has: a slider main body with an air bearing surface to a magnetic medium; two magnetic shield films which are parallel disposed on a common plane with a predetermined interval and orthogonal to air flow on the downstream side of the air bearing surface of the slider main body; a magnetoresistive effect head which is disposed through a magnetic separating layer of an insulator between the two magnetic shield films; an inductive head which is composed of one magnetic pole film corresponding to one of the two magnetic shield films which is located downstream and the other magnetic pole film which is disposed through a magnetic gap on the other side of the one magnetic pole film where the magnetoresistive effect head does not exist, and recording is conducted by magnetic field which generates at the magnetic gap; and concave portions which are formed on both sides of the other magnetic pole film along the direction of the air flow on the air bearing surface of the slider main body so as

Abstract: In a magnetoresistive effect composite head, magnetic shields oppose each other on a slider main body made of a ceramic material through a predetermined gap, and a magnetoresistive effect element is sandwiched and stacked between the magnetic shields with a magnetic spacer layer made of an insulator. A recording head portion uses one of the magnetic shields as a first magnetic pole, and has a second magnetic pole formed on a surface of the first magnetic pole opposite to the magnetoresistive effect element through a magnetic gap, to record information on a recording medium by means of a magnetic field generated in the magnetic gap. The magnetoresistive effect element includes a central region made of a spin-valve element to sense a medium field, and end regions for supplying a bias field and a current to the central region. The second magnetic pole is constituted by a stacked film of first and second magnetic films having different saturation magnetizations.

Abstract: Disclosed is a merged head device which has: a slider main body with an air bearing surface to a magnetic medium; two magnetic shield films which are parallel disposed on a common plane with a predetermined interval and orthogonal to air flow on the downstream side of the air bearing surface of the slider main body; a magnetoresistive effect head which is disposed through a magnetic separating layer of an insulator between the two magnetic shield films; an inductive head which is composed of one magnetic pole film corresponding to one of the two magnetic shield films which is located downstream and the other magnetic pole film which is disposed through a magnetic gap on the other side of the one magnetic pole film where the magnetoresistive effect head does not exist, and recording is conducted by magnetic field which generates at the magnetic gap; and concave portions which are formed on both sides of the other magnetic pole film along the direction of the air flow on the air bearing surface of the slider ma

Abstract: A magnetoresistive effect composite head includes a read magnetoresistive effect (MR) head and a recording inductive (ID) head. The MR head has first and second magnetic shield films and an MR element. The first and second magnetic shield films are formed on a slider main body in a stacked manner through a predetermined gap therebetween. Each of the first and second magnetic shield films has an end face flush with a slider floating surface. The MR element is formed between the first and second magnetic shield films through magnetic isolation layers each made of an insulator. The ID head has a first magnetic pole film, a coil, and a second magnetic pole film. The first magnetic pole film serves also as the second magnetic shield film. The coil and the second magnetic pole film are formed through an insulator on the first magnetic pole film on a surface opposite to the MR element through a predetermined magnetic gap. The second magnetic pole film has a projecting portion that defines a track width.

Abstract: A power source apparatus where an exciting current of a primary winding of an insulating converter transformer is switched by a switching element and an oscillation state of an oscillating drive circuit connected to the switching element is controlled according to a secondary side output voltage of the insulating converter transformer for controlling the secondary side output voltage to be a constant voltage. Under the control of the oscillating drive circuit, a supplying path of the exciting current is changed over between two modes of a full bridge action and a single ended push-pull or half bridge action.

Abstract: An inductive head structure provided in a magnetoresistance effect composite head includes an inductive head and a magnetoresistance effect head, the inductive head structure including a magnetic gap layer sandwiched by first and second magnetic layers acting as magnetic poles, the first magnetic layer being positioned close to the magnetoresistance effect head, the magnetic gap layer being made of a non-magnetic and electrically insulative material, wherein the non-magnetic and electrically insulative material has a higher etching rate to reactive ion etching than at least a magnetic material of the second magnetic layer.