Abstract: A semiconductor device including a control signal generating circuit that outputs an exposure time switching pulse and a sweep period pulse, the exposure time switching pulse indicating a length of an exposure time in which light-receiving elements receive incident light, and the sweep period pulse specifying a time in which a ramp signal generating circuit sweeps a ramp signal; and a ramp waveform control circuit that stores a short-time exposure slope setting value and a long-time exposure slope setting value, switches between the short-time exposure slope setting value and the long-time exposure slope setting value according to the exposure time switching pulse, and outputs the switched one of the short-time exposure slope setting value and the long-time exposure slope setting value, the short-time exposure slope setting value setting a slope of the ramp signal used when the exposure time switching pulse indicates a short-time exposure period.

Abstract: An imaging device is provided which can secure the dynamic range of a COMS imaging sensor, by storing a charge overflowing from a floating diffusion in a storage capacitance element and suppressing the increase of a pixel area which occurs if the storage capacitance element is formed by a MOS capacitor. The imaging device includes plural pixel circuits arranged in the row direction and the column direction, and plural storage capacitance lines arranged in the row direction and extending in the column direction. Each of the storage capacitance lines is coupled to the pixel circuits arranged in the same column. The pixel circuit includes a first photoelectric conversion element which stores a charge generated by being subjected to light, a floating diffusion to which the charge stored in the first photoelectric conversion element is transferred, and a first switching transistor coupling the floating diffusion and the storage capacitance line.

Abstract: A semiconductor device including a control signal generating circuit that outputs an exposure time switching pulse and a sweep period pulse, the exposure time switching pulse indicating a length of an exposure time in which light-receiving elements receive incident light, and the sweep period pulse specifying a time in which a ramp signal generating circuit sweeps a ramp signal; and a ramp waveform control circuit that stores a short-time exposure slope setting value and a long-time exposure slope setting value, switches between the short-time exposure slope setting value and the long-time exposure slope setting value according to the exposure time switching pulse, and outputs the switched one of the short-time exposure slope setting value and the long-time exposure slope setting value, the short-time exposure slope setting value setting a slope of the ramp signal used when the exposure time switching pulse indicates a short-time exposure period.

Abstract: An imaging device is provided which can secure the dynamic range of a COMS imaging sensor, by storing a charge overflowing from a floating diffusion in a storage capacitance element and suppressing the increase of a pixel area which occurs if the storage capacitance element is formed by a MOS capacitor. The imaging device includes plural pixel circuits arranged in the row direction and the column direction, and plural storage capacitance lines arranged in the row direction and extending in the column direction. Each of the storage capacitance lines is coupled to the pixel circuits arranged in the same column. The pixel circuit includes a first photoelectric conversion element which stores a charge generated by being subjected to light, a floating diffusion to which the charge stored in the first photoelectric conversion element is transferred, and a first switching transistor coupling the floating diffusion and the storage capacitance line.

Abstract: Conventional semiconductor devices disadvantageously failed to sufficiently enlarge a dynamic range. A semiconductor device according to an embodiment includes a plurality of registers 21 to 26 that sets a gradient of a ramp signal. In the semiconductor device, the values in the registers 24 to 26 that are reflected in the gradient of the ramp signal are switched at predetermined timings, whereby a ramp signal with a gradient that changes at the predetermined timings is generated, and an analog-to-digital converter uses the ramp signal to convert pixel signals acquired from a pixel area into digital values.

Abstract: A problem in conventional semiconductor devices is that a frame rate for acquiring images cannot be increased. A semiconductor device according to one embodiment sets a slope of a ramp signal provided to an analog-to-digital converter for converting pixel signals into digital values such that it becomes large in a conversion process corresponding to short-time exposure whereas it becomes small in a conversion process corresponding to long-time exposure, sets a sweep time of the ramp signal such that it becomes short in the conversion process corresponding to the short-time exposure, whereas it becomes long in the conversion process corresponding to the long-time exposure, and generates two pieces of data such that the number of bits in a digital value corresponding to the short-time exposure will become smaller than the number of bits in the digital value corresponding to the long-time exposure.

Abstract: A CMOS image sensor used as a solid-state image sensing device includes a pixel circuit for outputting a voltage of a level corresponding to the illuminance, and an A/D converter for converting an output voltage of the pixel circuit into a digital signal. The resolution on the low illuminance side is higher than the resolution on the high illuminance side in the A/D converter. Thus, the dynamic range can be increased and the operation speed can be increased, compared to the case in which the resolution is constant independent of the illuminance.

Abstract: An imaging device is provided which can secure the dynamic range of a COMS imaging sensor, by storing a charge overflowing from a floating diffusion in a storage capacitance element and suppressing the increase of a pixel area which occurs if the storage capacitance element is formed by a MOS capacitor. The imaging device includes plural pixel circuits arranged in the row direction and the column direction, and plural storage capacitance lines arranged in the row direction and extending in the column direction. Each of the storage capacitance lines is coupled to the pixel circuits arranged in the same column. The pixel circuit includes a first photoelectric conversion element which stores a charge generated by being subjected to light, a floating diffusion to which the charge stored in the first photoelectric conversion element is transferred, and a first switching transistor coupling the floating diffusion and the storage capacitance line.

Abstract: Conventional semiconductor devices disadvantageously failed to sufficiently enlarge a dynamic range. A semiconductor device according to an embodiment includes a plurality of registers 21 to 26 that sets a gradient of a ramp signal. In the semiconductor device, the values in the registers 24 to 26 that are reflected in the gradient of the ramp signal are switched at predetermined timings, whereby a ramp signal with a gradient that changes at the predetermined timings is generated, and an analog-to-digital converter uses the ramp signal to convert pixel signals acquired from a pixel area into digital values.

Abstract: A CMOS image sensor used as a solid-state image sensing device includes a pixel circuit for outputting a voltage of a level corresponding to the illuminance, and an A/D converter for converting an output voltage of the pixel circuit into a digital signal. The resolution on the low illuminance side is higher than the resolution on the high illuminance side in the A/D converter. Thus, the dynamic range can be increased and the operation speed can be increased, compared to the case in which the resolution is constant independent of the illuminance.

Abstract: An imaging device is provided which can secure the dynamic range of a COMS imaging sensor, by storing a charge overflowing from a floating diffusion in a storage capacitance element and suppressing the increase of a pixel area which occurs if the storage capacitance element is formed by a MOS capacitor. The imaging device includes plural pixel circuits arranged in the row direction and the column direction, and plural storage capacitance lines arranged in the row direction and extending in the column direction. Each of the storage capacitance lines is coupled to the pixel circuits arranged in the same column. The pixel circuit includes a first photoelectric conversion element which stores a charge generated by being subjected to light, a floating diffusion to which the charge stored in the first photoelectric conversion element is transferred, and a first switching transistor coupling the floating diffusion and the storage capacitance line.

Abstract: A problem in conventional semiconductor devices is that a frame rate for acquiring images cannot be increased. A semiconductor device according to one embodiment sets a slope of a ramp signal provided to an analog-to-digital converter for converting pixel signals into digital values such that it becomes large in a conversion process corresponding to short-time exposure whereas it becomes small in a conversion process corresponding to long-time exposure, sets a sweep time of the ramp signal such that it becomes short in the conversion process corresponding to the short-time exposure, whereas it becomes long in the conversion process corresponding to the long-time exposure, and generates two pieces of data such that the number of bits in a digital value corresponding to the short-time exposure will become smaller than the number of bits in the digital value corresponding to the long-time exposure.

Abstract: Conventional semiconductor devices disadvantageously failed to sufficiently enlarge a dynamic range. A semiconductor device according to an embodiment includes a plurality of registers 21 to 26 that sets a gradient of a ramp signal. In the semiconductor device, the values in the registers 24 to 26 that are reflected in the gradient of the ramp signal are switched at predetermined timings, whereby a ramp signal with a gradient that changes at the predetermined timings is generated, and an analog-to-digital converter uses the ramp signal to convert pixel signals acquired from a pixel area into digital values.

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.

Abstract: An imaging device is provided which can secure the dynamic range of a COMS imaging sensor, by storing a charge overflowing from a floating diffusion in a storage capacitance element and suppressing the increase of a pixel area which occurs if the storage capacitance element is formed by a MOS capacitor. The imaging device includes plural pixel circuits arranged in the row direction and the column direction, and plural storage capacitance lines arranged in the row direction and extending in the column direction. Each of the storage capacitance lines is coupled to the pixel circuits arranged in the same column. The pixel circuit includes a first photoelectric conversion element which stores a charge generated by being subjected to light, a floating diffusion to which the charge stored in the first photoelectric conversion element is transferred, and a first switching transistor coupling the floating diffusion and the storage capacitance line.

Abstract: A CMOS image sensor used as a solid-state image sensing device includes a pixel circuit for outputting a voltage of a level corresponding to the illuminance, and an A/D converter for converting an output voltage of the pixel circuit into a digital signal. The resolution on the low illuminance side is higher than the resolution on the high illuminance side in the A/D converter. Thus, the dynamic range can be increased and the operation speed can be increased, compared to the case in which the resolution is constant independent of the illuminance.

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.

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.

Abstract: An AD-converted digital video data is encoded by a difference encoding method before it is outputted and such encoded digital video data is then outputted, after it is converted to gray code or to a predetermined code in which a fixed value is added. Problems solved include noise that is generated when the AD conversion circuit outputs video data and that migrates into a CCD side via a power supply line on a printed circuit board, and noise that appears on a display image by migration into an input terminal side from an output circuit side via the power supply line and a semiconductor substrate within an AD conversion LSI.

Abstract: An AD-converted digital video data is encoded by a difference encoding method before it is outputted and such encoded digital video data is then outputted, after it is converted to gray code or to a predetermined code in which a fixed value is added. Problems solved include noise that is generated when the AD conversion circuit outputs video data and that migrates into a CCD side via a power supply line on a printed circuit board, and noise that appears on a display image by migration into an input terminal side from an output circuit side via the power supply line and a semiconductor substrate within an AD conversion LSI.