Patents by Inventor Takayoshi Shigekura

Takayoshi Shigekura 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).

  • Ad converter and solid-state imaging apparatus using the same
    Patent number: 9143714
    Abstract: There is a need to provide an AD converter capable of reducing occurrence of a noise. An AD converter includes an operational amplifier and a clip circuit. The operational amplifier receives ramp voltage and voltage for an analog signal and allows output terminal voltage to transition from an H level to an L level when a change in the ramp voltage reaches the voltage for the analog signal. The clip circuit fixes an output terminal of the operational amplifier to clipping voltage after output voltage for the operational amplifier reaches threshold voltage for a latch circuit. Therefore, the AD converter can limit a range of output voltage, as a source of noise, for the operational amplifier and eliminate an unnecessary change in the output voltage after the threshold voltage for the latch circuit is reached.
    Type: Grant
    Filed: February 6, 2014
    Date of Patent: September 22, 2015
    Assignee: Renesas Electronics Corporation
    Inventors: Osamu Nishikido, Yasutoshi Aibara, Hirokazu Shimizu, Satoshi Tatsukawa, Takayoshi Shigekura
  • AD CONVERTER AND SOLID-STATE IMAGING APPARATUS USING THE SAME
    Publication number: 20140152879
    Abstract: There is a need to provide an AD converter capable of reducing occurrence of a noise. An AD converter includes an operational amplifier and a clip circuit. The operational amplifier receives ramp voltage and voltage for an analog signal and allows output terminal voltage to transition from an H level to an L level when a change in the ramp voltage reaches the voltage for the analog signal. The clip circuit fixes an output terminal of the operational amplifier to clipping voltage after output voltage for the operational amplifier reaches threshold voltage for a latch circuit. Therefore, the AD converter can limit a range of output voltage, as a source of noise, for the operational amplifier and eliminate an unnecessary change in the output voltage after the threshold voltage for the latch circuit is reached.
    Type: Application
    Filed: February 6, 2014
    Publication date: June 5, 2014
    Applicant: Renesas Electronics Corporation
    Inventors: Osamu NISHIKIDO, Yasutoshi Aibara, Hirokazu Shimizu, Satoshi Tatsukawa, Takayoshi Shigekura
  • Ad converter and solid-state imaging apparatus using the same
    Patent number: 8681032
    Abstract: There is a need to provide an AD converter capable of reducing occurrence of a noise. An AD converter includes an operational amplifier and a clip circuit. The operational amplifier receives ramp voltage and voltage for an analog signal and allows output terminal voltage to transition from an H level to an L level when a change in the ramp voltage reaches the voltage for the analog signal. The clip circuit fixes an output terminal of the operational amplifier to clipping voltage after output voltage for the operational amplifier reaches threshold voltage for a latch circuit. Therefore, the AD converter can limit a range of output voltage, as a source of noise, for the operational amplifier and eliminate an unnecessary change in the output voltage after the threshold voltage for the latch circuit is reached.
    Type: Grant
    Filed: December 6, 2012
    Date of Patent: March 25, 2014
    Assignee: Renesas Electronics Corporation
    Inventors: Osamu Nishikido, Yasutoshi Aibara, Hirokazu Shimizu, Satoshi Tatsukawa, Takayoshi Shigekura