The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 11, 1986
Filed:
Nov. 19, 1984
David E Norton, Jr, Boulder, CO (US);
Storage Technology Corporation, Louisville, CO (US);
Abstract
A write data transition detector is provided connected across a thin film write head and write current generator and is responsive to the fractional voltage drops across the head resulting from the fractional amperage currents passed by the write generator through the head. Circuits in the detector adjust the gain of the voltage difference across the head, remove voltage spikes induced by changes in current across the head and time the period between consecutive current reversals of sufficient magnitude. The timing is controlled by means of a hysteresis circuit which switches from an existing state to an alternate state only when there is a satisfactorily large reversal of current across the write head. A timing circuit connected with the hysteresis circuit capacitively times the length of the period the hysteresis circuit remains in its existing state and outputs a fault indication current when this period exceeds the maximum period between transitions allowed by the encoding scheme employed.