Structure and method for correction of defective analog data in a nonvolatile semiconductor memory

A nonvolatile semiconductor memory comprising:

• a memory unit having a plurality of memory cells to discretely store an analog signal such as an image signal, as analog data in the form of an analog value;
• a memory control unit for sequentially selecting said memory cells as a read out target of said memory unit in response to a predetermined clock;
• a defect position detection unit for detecting, on the basis of defect position information indicating a position of defective analog data included in the analog data read out from said memory unit, whether a memory cell corresponding to the defect position is selected by said memory control unit, and outputting a detection output;
• and
• a memory select switching unit arranged between said memory control unit and said memory unit to switchingly select another memory cell in place of said memory cell corresponding to the defect position if said detection output indicates that the memory cell corresponding to the defect position is selected by said memory control unit, said another memory cell storing analog data of said analog signal.

A nonvolatile semiconductor memory for storing an image signal indicating a color image obtained by an image sensing element such as a color CCD and having luminance values of primary colors that are different according to pixel positions of the color image, the luminance values being sequentially arranged on a time axis in the form of analog values, comprising:

• a memory unit having a plurality of memory cells to discretely store the luminance values at the respective pixel positions stored on the image signal as analog luminance data in the form of an analog value;
• a memory control unit for sequentially selecting said memory cells as a read out target of said memory unit in response to a predetermined clock;
• a data conversion unit for performing an arithmetic process of a plurality of other analog luminance data at pixel positions that are adjacent on the color image to each of selected pixel positions corresponding to selected analog luminance data stored in said selected memory cells, to calculate the analog luminance data of the primary colors at the selected pixel positions, and for outputting the calculated data as color image data;
• and
• a defect position detection unit for detecting, on the basis of defect position information indicating a position of defective data included in the analog luminance data read out from said memory unit, whether the analog luminance data used by said data conversion unit includes defective data, and outputting a detection output,
• wherein said memory unit comprises means for, when an arbitrary memory cell is selected by said memory control unit, outputting analog luminance data stored in said selected memory cell as selected analog luminance data, and reading out a plurality of other analog luminance data at pixel positions that are adjacent on a color image to selected pixel positions corresponding to the selected analog luminance data, and outputting the readout data from said memory cells, and
• said data conversion unit has:
• a data selection unit for outputting a plurality of the analog luminance data used for an arithmetic process if the detection output indicates that the analog luminance data used for the arithmetic process does not include defective data, and switchingly outputting in place of the defective data another one of the analog luminance data used for the arithmetic process if the detection output indicates that the analog luminance data used for the arithmetic process includes defective data;
• and
• an arithmetic processing unit for performing an arithmetic process of the analog luminance data output from said data selection unit to calculate analog luminance data of the primary colors.

A nonvolatile semiconductor memory for storing an image signal indicating a color image obtained by an image sensing element such as a color CCD and having luminance values of primary colors that are different according to pixel positions of the color image, the luminance values being sequentially arranged on a time axis in the form of analog values, comprising:

• a memory unit having a plurality of memory cells to discretely store the luminance values at the respective pixel positions stored on the image signal as analog luminance data in the form of an analog value;
• a memory control unit for sequentially selecting said memory cells as a read out target of said memory unit in response to a predetermined clock;
• a data conversion unit for performing an arithmetic process of a plurality of other analog luminance data at pixel positions that are adjacent on the color image to each of selected pixel positions corresponding to selected analog luminance data stored in said selected memory cells, to calculate the analog luminance data of the primary colors at the selected pixel positions, and for outputting the calculated data as color image data;
• and
• a defect position detection unit for detecting, on the basis of defect position information indicating a position of defective data included in the analog luminance data read out from said memory unit, whether the analog luminance data used by said data conversion unit includes defective data, and outputting a detection output,
• wherein said memory unit comprises means for, when an arbitrary memory cell is selected by said memory control unit, outputting analog luminance data stored in said selected memory cell as selected analog luminance data, and reading out a plurality of other analog luminance data at pixel positions that are adjacent on the color image to selected pixel positions corresponding to the selected analog luminance data, and outputting the readout data from said memory cells, and
• said data conversion unit has:
• a synthesizer for amplifying the plurality of analog luminance data used for the arithmetic process and thereafter synthesizing the amplified analog luminance data;
• and
• a gain setting unit for setting a gain value corresponding to each of the plurality of analog luminance data used for the arithmetic process to be equal if the detection output indicates that the analog luminance data used for the arithmetic process does not include defective data, and decreasing a gain value corresponding to defective data and uniformly increasing gain values corresponding to other correct analog luminance data if the detection output indicates that the analog luminance data used for the arithmetic process includes defective data.