Patents by Inventor Donal P. Geraghty

Donal P. Geraghty has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 7555394
    Abstract: A single chip integrated circuit measuring circuit (1) for determining a characteristic of the impedance of an external complex impedance circuit (2) for facilitating characterization of the impedance of the complex impedance circuit (2) comprises a signal generating circuit (7) for generating a variable frequency stimulus signal for applying to the complex impedance circuit (2). A first receiving circuit (10) receives a response signal from the complex impedance circuit (2) in response to the stimulus signal and conditions the response signal. A first analog-to-digital converter (68) converts the conditioned response signal to a first digital output signal, which is read from the first analog-to-digital converter (68) through a first digital output port (14). The response signal from the complex impedance circuit (2) is a current signal, and a current to voltage converter circuit (64) converts the response signal to a voltage signal.
    Type: Grant
    Filed: July 24, 2006
    Date of Patent: June 30, 2009
    Assignee: Analog Devices, Inc.
    Inventors: James F. Caffrey, Colm F. Slattery, Albert C. O'Grady, Colin Gerard Lyden, Donal P. Geraghty, Sean Smith
  • Patent number: 6985100
    Abstract: A multi-channel integrated circuit comprises a plurality of channels (CH1 to CH20). A DAC (3) is provided in each channel (CH1 to CH20) for converting digital data inputted to the circuit (1) through an I/O port (14). Digital data to be converted by the DACs (3) is selectively applied to input registers (10) of each channel (CH1 to CH20) on a digital data bus (16) under the control of an interface and control logic circuit (15). The digital words written to the input registers (10) are in turn written to DAC registers (9) through corresponding digital switches (12) for conversion by the DACs (3). A clear code register (22) stores a clear code for writing to the DAC registers (9) in response to a clear signal applied to a clear terminal (24) of the circuit (1) so that analogue outputs appearing on output terminals (5) of the channels (CH1 to CH20) are of a predetermined value, typically, zero volts, when the circuit (1) is set in a clear condition.
    Type: Grant
    Filed: December 9, 2003
    Date of Patent: January 10, 2006
    Assignee: Analog Devices, Inc.
    Inventors: Donal P. Geraghty, Denis Martin O'Connor, Dennis Arnold Dempsey
  • Patent number: 6924759
    Abstract: A multi-channel circuit (1) comprising a plurality of on-chip channels (CH1 to CH4), each of which comprises a DAC (3) for converting digital data into analogue output signals independently of each other under the control of an interface and control logic circuit (11). The analogue output signals from the DACs (3) are outputted on output terminals (7) of the respective channels (CH1 to CH4). The digital input data and control and address signals for controlling the conversion of the digital data in the DACs (3) are inputted to the interface and control logic circuit (11) through an I/O port (10). DAC registers (9) are provided in the respective channels (CH1 to CH4) for storing the digital words to be converted in the corresponding DACs (3). Analogue input terminals (20) are provided for receiving analogue input signals (20), for example, analogue signals from external systems which may be controlled by the output signals from the DACs (3).
    Type: Grant
    Filed: December 9, 2003
    Date of Patent: August 2, 2005
    Assignee: Analog Devices, Inc.
    Inventors: John Wynne, Donal P. Geraghty, Albert C. O'Grady
  • Patent number: 6885329
    Abstract: A signal generator (1) for generating a square waveform analog voltage output signal comprises an on-chip DAC (12) which outputs the analog voltage signal on an output terminal (5). On-chip first and second programmable registers (9,10) store first and second digital words which correspond to the maximum and minimum voltage values of the analog output signal. An on-chip switch circuit (15) selectively and alternately switches the first and second registers (9,10) to an on-chip DAC register (17) from which the respective first and second digital words are loaded into the DAC (12) in response to a load DAC signal generated by a control circuit (14). The load DAC signal is generated in response to an externally generated LDAC signal in the form of a clock signal which is applied to an LDAC terminal (22). A flip-flop (19) in response to the load DAC signal outputs a control signal on a control line (25) for alternately switching the first and second registers (9,10) to the DAC register (17).
    Type: Grant
    Filed: June 10, 2004
    Date of Patent: April 26, 2005
    Assignee: Analog Devices, Inc.
    Inventors: Donal P. Geraghty, Albert C. O'Grady, Tudor M. Vinereanu
  • Publication number: 20040145507
    Abstract: A signal generator (1) for generating a square waveform analog voltage output signal comprises an on-chip DAC (12) which outputs the analog voltage signal on an output terminal (5). On-chip first and second programmable registers (9,10) store first and second digital words which correspond to the maximum and minimum voltage values of the analog output signal. An on-chip switch circuit (15) selectively and alternately switches the first and second registers (9,10) to an on-chip DAC register (17) from which the respective first and second digital words are loaded into the DAC (12) in response to a load DAC signal generated by a control circuit (14). The load DAC signal is generated in response to an externally generated LDAC signal in the form of a clock signal which is applied to an LDAC terminal (22). A flip-flop (19) in response to the load DAC signal outputs a control signal on a control line (25) for alternately switching the first and second registers (9,10) to the DAC register (17).
    Type: Application
    Filed: January 29, 2003
    Publication date: July 29, 2004
    Inventors: Donal P. Geraghty, Albert C. O'Grady, Tudor M. Vinereanu
  • Publication number: 20040119625
    Abstract: A multi-channel integrated circuit comprises a plurality of channels (CH1 to CH20). A DAC (3) is provided in each channel (CH1 to CH20) for converting digital data inputted to the circuit (1) through an I/O port (14). Digital data to be converted by the DACs (3) is selectively applied to input registers (10) of each channel (CH1 to CH20) on a digital data bus (16) under the control of an interface and control logic circuit (15). The digital words written to the input registers (10) are in turn written to DAC registers (9) through corresponding digital switches (12) for conversion by the DACs (3). A clear code register (22) stores a clear code for writing to the DAC registers (9) in response to a clear signal applied to a clear terminal (24) of the circuit (1) so that analogue outputs appearing on output terminals (5) of the channels (CH1 to CH20) are of a predetermined value, typically, zero volts, when the circuit (1) is set in a clear condition.
    Type: Application
    Filed: December 9, 2003
    Publication date: June 24, 2004
    Inventors: Donal P. Geraghty, Denis Martin O'Connor, Dennis Arnold Dempsey
  • Publication number: 20040113177
    Abstract: A multi-channel circuit (1) comprising a plurality of on-chip channels (CH1 to CH4), each of which comprises a DAC (3) for converting digital data into analogue output signals independently of each other under the control of an interface and control logic circuit (11). The analogue output signals from the DACs (3) are outputted on output terminals (7) of the respective channels (CH1 to CH4). The digital input data and control and address signals for controlling the conversion of the digital data in the DACs (3) are inputted to the interface and control logic circuit (11) through an I/O port (10). DAC registers (9) are provided in the respective channels (CH1 to CH4) for storing the digital words to be converted in the corresponding DACs (3). Analogue input terminals (20) are provided for receiving analogue input signals (20), for example, analogue signals from external systems which may be controlled by the output signals from the DACs (3).
    Type: Application
    Filed: December 9, 2003
    Publication date: June 17, 2004
    Inventors: John Wynne, Donal P. Geraghty, Albert C. O'Grady