Abstract: A device for digitally shaping the quantization noise of an N-bit digital signal, N being a positive integer, comprises: a register for masking out selected bits of the N-bit digital signal to produce an M-bit digital signal, M being a positive integer less than N; a digital noise-shaping coder, coupled to the register, for shaping the quantization noise of the masked out bits; and an accumulator, coupled to the register and the coder, for accumulating the digital signals received from the register and the coder. Likewise, a method of digitally shaping the quantization noise of an N-bit digital signal, N being a positive integer, comprises the steps of: masking selected bits of an N-bit digital signal to produce an M-bit digital signal, M being a positive integer less than N; digitally coding the masked bits of the N-bit digital signal to produce a B-bit digital signal, B being a positive integer less than N-M; and accumulating the M-bit digital signal and the B-bit digital signal.
Type:
Grant
Filed:
December 21, 1993
Date of Patent:
June 13, 1995
Assignee:
AT&T Corp.
Inventors:
Steven R. Norsworthy, Rich: David A., Thayamkulangara R. Viswanathan
Abstract: A variable gain voltage signal amplifier is provided for incorporation in an automatic gain control circuit, such as for a disk drive. The variable gain voltage signal amplifier comprises: an amplifier including an inverting input voltage signal terminal and an output voltage signal terminal. The amplifier includes an input signal path coupled to the input voltage signal terminal and further includes a feedback signal path coupling between the input voltage signal terminal and the output voltage signal terminal. The input signal path comprises a capacitor coupled in series with a resistor, and the feedback signal path comprises a resistor. At least one of the resistors comprises an electronic signal-controlled resistor.
Type:
Grant
Filed:
December 13, 1993
Date of Patent:
May 2, 1995
Assignee:
AT&T Corp.
Inventors:
Harley F. Burger, Jr., John M. Khoury, Tandur L. Viswanathan
Abstract: A moisture-proof integrated circuit module includes at least one integrated circuit component in a high density interconnect (HDI) structure fabricated by applying to a substrate successive multiple ply sequences having a plurality of via holes therein. The sequences overlie the component(s) and the module substrate, and each sequence includes a dielectric film and a plurality of lands comprised of metal that extends into the vias of the sequence to provide electrical interconnections. The module includes at least one moisture barrier film to prevent penetration of moisture through the module to the circuit component(s).
Type:
Grant
Filed:
November 14, 1991
Date of Patent:
March 1, 1994
Assignee:
General Electric Company
Inventors:
Constantine A. Neugebauer, Herbert S. Cole, Eugene L. Bartels, Raymond A. Fillion
Abstract: A method for fabricating a metal interconnection pattern for an integrated circuit module is provided comprising the steps of: aligning only one face of the module, forming a metal layer on at least one other face of the module, applying a coating of photoresist to the metal layer, exposing predetermined portions of the photoresist to reflected radiation, and shaping the metal layer in accordance with the exposed photoresist portions.
Type:
Grant
Filed:
October 13, 1992
Date of Patent:
January 18, 1994
Assignee:
General Electric Company
Inventors:
Ernest W. Balch, Stanton E. Weaver, Jr., William H. King, Bernard Gorowitz
Abstract: An ultraviolet light filter is provided by implanting an ultraviolet light absorbing chemical species into an ultraviolet light transmissive substrate. Two such filters having gradient distributions may be overlapped and shifted relative to each other to provide adjustable attenuation.
Abstract: A drop-on-demand ink jet print head (9) has an ink pressure chamber (22) coupled to a source of ink (11) and an ink drop ejecting orifice (103) with an ink drop ejection orifice outlet (14). An acoustic driver (36), in response to a driver signal (100), produces a pressure wave in the ink and causes the ink to pass outwardly through the ink drop ejecting orifice (103) and the ink jet ejection orifice outlet (14) of the ink jet print head (9). In accordance with the present invention, controlling the operation of the ink jet print head (9) with a particular drive signal reduces print quality degradation resulting from rectified diffusion, which is the growth of air bubbles dissolved in the ink from the repeated application of pressure pulses to the ink residing within the ink pressure chamber (22) of the ink jet print head (9), such pressure pulses causing the application of pressures below ambient pressure.
Type:
Grant
Filed:
March 6, 1991
Date of Patent:
October 13, 1992
Assignee:
Tektronix, Inc.
Inventors:
Joy Roy, Douglas M. Stanley, James D. Buehler, Ronald L. Adams