Abstract: The present invention relates to circuitry for processing an analog read signal, such as a signal produced by a magnetoresistive head, in a magnetic data storage system. The circuitry processes the analog signal before the signal reaches the detector which converts the analog signal into a digital signal representative of the data originally stored on the magnetic medium. In one embodiment, the invention comprises circuitry for equalizing the amplitudes of the positive and negative pulses in the analog read signal. In another embodiment, the invention comprises circuitry for reducing the baseline shift of the analog read signal. The invention may be used in magnetic data storage systems using any conventional data detection method.

Abstract: A method for fabricating a dual element head is disclosed. One embodiment includes first depositing a first head element upon a substrate and second depositing a second head element upon the first head element. Each of the depositing steps includes a tolerance that is independent of the other. In the second depositing step, the functional width of the second head element (i.e., the write width if the second head element is a write element) is made wider than a desired functional width for the second head element. The second head element is then trimmed to substantially achieve the desired functional width while using a portion of the first head element as a reference to reduce errors associated with the independent nature of the first and second tolerances. For instance, the portion of the first head element used as a reference can be an edge of a magnetoresistive (MR) read element that defines the read width of the read element.

Abstract: A head positioning system accurately positions a read/write head along a selected track of a rotating magnetic disk. In one aspect, servo information is embedded along the track with the centerline of the servo information offset a radial distance from the centerline of data stored or written along the track. The head positioning system micro-jogs the read/write head a first and a second radial distance from the centerline of servo information for a read operation and a write operation.

Abstract: A head positioning system accurately positions a read/write head along a selected track of a rotating magnetic disk. In one aspect, servo information is embedded along the track with the centerline of the servo information offset a radial distance from the centerline of data stored or written along the track. The head positioning system micro-jogs the read/write head a first and a second radial distance from the centerline of servo information for a read operation and a write operation.

Abstract: The present invention relates to circuitry for processing an analog read signal, such as a signal produced by a magnetoresistive head, in a magnetic data storage system. The circuitry processes the analog signal before the signal reaches the detector which converts the analog signal into a digital signal representative of the data originally stored on the magnetic medium. In one embodiment, the invention comprises circuitry for equalizing the amplitudes of the positive and negative pulses in the analog read signal. In another embodiment, the invention comprises circuitry for reducing the baseline shift of the analog read signal. The invention may be used in magnetic data storage systems using any conventional data detection method.

Abstract: A dual element head is provided that includes a read element and a separate write element, wherein the read width of the read element is greater than the write width of the write element. The head also includes an erase notch for creating an erase strip along the edge of data written by the write element during a write operation. The width of the erase strip is optimized so that undesired data on the track, that could otherwise be read by the wider read element during a subsequent read operation, is removed during the write operation.

Abstract: A vertical recording head structure combines a tri-pad shaped slider body with a uniquely shaped thin-film recording element disposed along a trailing edge of the slider body. The recording element, or transducer, includes a narrow probe tip for writing data to a rotating magnetic disk. The recording element also includes a wide permalloy area to distribute the magnetic field returning from the disk. The wide area spreads the magnetic field lines such that the returning flux is kept from unintentional writing or reading information. The size and orientation of the air-bearing surfaces on the tri-pad slider body causes the slider to assume a flying attitude wherein the leading edge is lifted above the rotating magnetic disk, and the trailing edge is in substantial contact with the disk, during data transfer operations.

Abstract: A resonant frequency control circuit communicates with a head of a disk drive and the preamplifier of a read channel. The resonant frequency control circuit is useful in achieving peaking of a readback signal generated by reading data from a magnetic disk. The read channel also includes an equalizer circuit for enhancing equalization of the readback signal. A controller communicates with the read channel and the resonant frequency control circuit for, in one embodiment, selectively adding capacitance to that capacitance which is present in the read element of the head and the preamplifier. By controlling the resonant frequency, this desired signal peaking can be achieved, which is related to the frequencies of the coded data on the disk.

Abstract: A pulse detection sensing system which provides an output signal only when a maximum voltage peak is detected. The system has a comparator which generates a comparator output signal when an output signal generated by the transducer of the system is equal to or greater than a threshold signal. The comparator is coupled to a peak follower and a sample/hold circuit which increases the voltage of the threshold signal to the level of the head output signal when the output signal attains a zero slope and has equaled or exceeded the set threshold value.

Abstract: A magnetic head that vertically records information on a disk and which creates erase bands between the disk tracks. The head has a single pole that has a pair of erase band segments which extend from a center pole section. When the head is writing information, the erase band segments create erase bands at the outer edges of the track by not fully magnetizing the disk and/or increasing the azimuth angle of the magnetized outer edges. The azimuth angle can be increased by constructing the outer segments of the pole to extend at an angle from the center pole section. The reduction in field strength in the outer track edges can be accomplished by making the outer pole segments thinner to cause a saturation of the outer magnetic field. The weaker, angled outer track portions do not generate a significant magnetic field in a head located on an adjacent track, thereby in effect creating erase bands in the disk.