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:
Jun. 26, 1979
Filed:
May. 01, 1978
Sidney J Schwartz, Vista, CA (US);
Burroughs Corporation, Detroit, MI (US);
Abstract
In a bubble memory system having a detector device for sensing the presence or absence of magnetic bubbles in a bubble stream and producing an output signal accordingly which is sensed by a differential sense amplifier having a clamp circuit to select the voltage level with which the signal is to be compared at a sampling time and a strobe circuit for sampling the signal at the preselected time, a dynamic input signal offset for enhancing the signal-to-noise factor at the input to the sense amplifier so that a signal representing an absence of a bubble is clearly distinguishable over a bubble presence signal. This invention disclosed is disclosed as operable with a d.phi./dt or magnetoresistive bridge type detectors and comprises means for shifting the signal level negatively by providing a negative going pulse just after the time the clamp circuit is released and while the signal is being sampled. In one embodiment of this invention, the negative going pulse is applied inductively and in another embodiment the negative going pulse is applied capacitively. The point of implementation of the dynamic input signal may be either within the bubble device itself or contained in a circuit board to which both the bubble device and sense amplifier interfaces.