Abstract: A wearable infusion pump assembly includes a reservoir for receiving an infusible fluid, and an external infusion set configured to deliver the infusible fluid to a user. A fluid delivery system is configured to deliver the infusible fluid from the reservoir to the external infusion set. The fluid delivery system includes a volume sensor assembly, and a pump assembly for extracting a quantity of infusible fluid from the reservoir and providing the quantity of infusible fluid to the volume sensor assembly. The volume sensor assembly is configured to determine the volume of at least a portion of the quantity of fluid. The fluid delivery system further includes at least one optical sensor assembly configured to sense the movement of the pump assembly, a first valve assembly configured to selectively isolate the pump assembly from the reservoir, and a second valve assembly configured to selectively isolate the volume sensor assembly from the external infusion set.

Abstract: A method and apparatus is disclosed for adaptively controlling the biasing current applied to magnetoresistive (MR) read heads within a magnetic disk drive to provide optimized bias for each head/disk/channel component combination. An optimized bias current for each head is ascertained and stored on the disk surface at the time of manufacture. During each power up operation the values are transferred to random access memory which is accessed during the execution of each head switch command to apply bias current in accordance with the optimized value to the active MR head. Periodic reoptimization and updating of the stored values is effected by general error measurement circuitry that forms a part of the device control system and is invoked to perform the reoptimization upon the occurrence of an event such as a predetermined duration of power on operation subsequent to the last reoptimization procedure.

Abstract: Apparatus and method of thermal asperity compensation are provided for data detection in a partial-response maximum-likelihood (PRML) data channel. The PRML data channel includes an analog to digital converter (ADC) having a normal operating range and a filter, gain and timing control coupled to the ADC. When a thermal asperity is detected, a thermal asperity recovery mode is established responsive to the detected thermal asperity. The gain and timing control are held and the normal operating range of the ADC is adjusted responsive to the thermal asperity recovery mode. Also an AC coupling pole frequency is elevated responsive to the thermal asperity recovery mode.

Abstract: A method and apparatus are provided for measuring flying height changes of a transducer head relative to a disk surface of a rotating disk in a disk file. A predetermined pattern is written on at least one predetermined region of the disk file. The predetermined region is normally not rewritten during operation of the disk file. At least one readback signal is sensed from at least one predetermined region of the disk surface. A plurality of sample values are identified corresponding to each readback signal. A change in the flying height is calculated utilizing the identified sample values. A frequency equalization number K can be utilized to calculate the magnitude and sign of the flying height change. Alternatively, real-time digital analysis of a predetermined pattern written on at least one predetermined region of the disk surface can be utilized to calculate the magnitude and sign of the flying height change.

Abstract: In a disk drive providing amplitude sampling data detection, the amplitude of an analog read back signal is sampled at data clock intervals. The resulting analog values are converted to digital equivalent values. The digital equivalent values are each compared to an expected digital values that is representative of the data that was originally recorded on the disk, to thereby generate a different value. The resulting collection of difference values are magnitude segregated, and then stored in a plurality of registers, for later use in providing a histogram that is a measure of the disk drive's read error rate.

Abstract: A magnetic disk drive channel circuitry is shown and described that generates eight incremental values of write current and eight incremental values of delta-V (the minimum voltage change per unit time which tests signals to discriminate between data and noise). Each of these variable parameter values may be program selected by a three bit bus signal. This variability testing of an adaptation to the optimum parameter value for each head media combination and by grouping tracks in contiguous data bands, the parameters may be optimized for tracks near the inner diameter, the outer diameter and in the middle band. The variable delta-V can also be used as an additional data recovery tool wherein re-reading with a lower value enhances recovery of missing bit errors and re-reading with an increased value can assist recovery from an extra bit error.