Individual MR transducer head/disk/channel adaptive bias current system

摘要

In a magnetic data storage device having data recorded in tracks on a media surface and including at least one magnetoresistive (MR) transducer read heads, the adaptive control method for the read head bias current involves determining an optimised bias current value for each MR head. The optimised values are stored, and the active MR head is supplied with a bias current in accordance with the stored value. The optimised bias current value is periodically re-determined for each MR head, and the stored bias current values are revised to correspond with the new optimised bias current values. The bias current values are stored on a disk media surface and are transferred from disk storage to random access memory during the power up sequence of the device.