IBM Assigned Patent

International Business Machines Corp., Armonk, NY, has been assigned a patent (8,254,048) developed by four co-inventors for a "dual gain control for magnetic data storage system."

The co-inventors are Jacob Lee Dahle, Tucson, AZ, Robert Allen Hutchins, Sedat Oelcer, Kilchberg, Kilchberg, Switzerland, and Larry LeeRoy Tretter, Tucson, AZ.

The abstract of the patent published by the U.S. Patent and Trademark Office states: "A system according to one embodiment includes an analog input for receiving an analog signal; a variable gain amplifier coupled to the analog input; a first gain control circuit coupled to the variable gain amplifier for controlling the gain of the analog signal; an analog to digital converter for converting the analog signal to a digital signal; a first gain error generation circuit for generating a first gain error signal based on an output of the analog to digital converter, the first gain error signal or derivative thereof being received by the first gain control circuit; and a second gain error generation circuit for generating a second gain error signal based on the digital signal, the second gain error signal or derivative thereof being received by the first gain control circuit, wherein the first gain control circuit uses at least one of the gain error signals to control the gain of the analog signal."

The patent application was filed on May 5, 2011 (13/101,969).