摘要:
A disc drive includes a base and a disc rotatably attached to the base. The disc drive also includes an actuator assembly rotatably attached to said base and a device for moving the actuator assembly. The actuator assembly includes an actuator arm and a transducer head in a transducing relationship with respect to the disc. The transducer is attached to the actuator arm. A method for screening disc drives for resonant frequencies associated with the actuator arm includes the steps of following a track within the disc drive, and selectively boosting the servo control signal. The method further includes a step of monitoring a position error signal from a transducer attached to an actuator arm of a disc drive. The position error signal is monitored by filtering the position error signal using a bandpass filter. Boosting the servo control loop includes tuning the magnitude of the booster signal gain.
摘要:
A data storage device has a plurality of head/surface combinations with different data track densities on at least two surfaces. A minimum head quality is established for the data storage apparatus. Head quality is identified for each of the heads at each of a plurality of track densities. A tuned track density is selected for each surface based on the track density that corresponds to a head quality.
摘要:
Method and apparatus for increasing process yields of data storage devices which store data on media surfaces using read/write heads. An initial linear bit recording density is determined for each head, the linear bit recording density comprising a density at which each head is capable of writing data to and reading data from the corresponding media surface. Defective storage sectors are identified on the media surfaces to determine whether a sufficient number of logical storage sectors are available to meet a predetermined data storage capacity. The linear bit recording density of at least one of the heads is then altered to ensure that the storage device has sufficient logical storage sectors to meet the predetermined capacity.
摘要:
A method sets bit densities and track densities for a plurality of heads in a data storage device. The method includes determining an initial bit density and an initial track density for each head. An initial total capacity for the storage device is determined based on the initial track densities and the initial bit densities. A desired capacity for the storage device is selected and the initial total capacity and the desired capacity are compared. One of either a bit density or a track density is then adjusted so that the data storage device has an adjusted capacity that provides some excess capacity over the desired capacity where the excess capacity is less than any excess capacity that was present between the initial capacity and the desired capacity. A data storage device formed through this method is also provided.
摘要:
A method, and system configured to implement the method, are provided. The method includes the steps of identifying a last usable track on a surface as a function of a parameter, and defining a standoff band of tracks relative to the last usable track to obtain an achieved maximum track on the surface. The last usable track is, in exemplary embodiments, a track beyond a default maximum track on a surface of a data storage medium.
摘要:
A buffer random access memory has a first portion reserved for a defect table and a second portion reserved for data caching. A method of managing the buffer random access memory includes determining actual memory space of the first portion which is occupied by the defect table. This identifies unused memory space of the first portion of the buffer random access memory. The method then includes reallocating the unused memory space of the first portion of the buffer random access memory for use in data caching. Controllers and mass storage devices which implement the method are also provided.
摘要:
Method and apparatus for determining a signal-to-noise ratio (SNR) value from a readback signal, such as in a data storage device. A readback signal is obtained by a receiver (such as a data transducing head) coupled to a data recovery channel having a variable gain amplifier (VGA) and a threshold detector (TD). The data channel applies a selectable VGA gain value to the readback signal while errors are accumulated using a selectable error detection threshold from the TD. The SNR value is determined at least from a magnitude of the error detection threshold, and preferably from first and second VGA gain values using a linear regression model. The determined SNR value is highly correlated to classical SNR values obtained using external equipment such as an analyzer or oscilloscope, and is advantageously used in automated fashion during high volume manufacturing certification testing.
摘要:
An apparatus and associated method for detecting head collision with disc media, or other matter, during a write operation is disclosed. The method and apparatus generally monitor the resistance of an MR element on the head in order to detect a temperature increases indicative of a head collision. The resistance can be compared to a pre-selected threshold to generate an output indicative of head collision.
摘要:
A buffer random access memory has a first portion reserved for a defect table and a second portion reserved for data caching. A method of managing the buffer random access memory includes determining actual memory space of the first portion which is occupied by the defect table. This identifies unused memory space of the first portion of the buffer random access memory. The method then includes reallocating the unused memory space of the first portion of the buffer random access memory for use in data caching. Controllers and mass storage devices which implement the method are also provided.
摘要:
A method, and system configured to implement the method, are provided. The method includes the steps of identifying a last usable track on a surface as a function of a parameter, and defining a standoff band of tracks relative to the last usable track to obtain an achieved maximum track on the surface. The last usable track is, in exemplary embodiments, a track beyond a default maximum track on a surface of a data storage medium.