Abstract: An image sensor with an array of pixels is provided. In order to determine failure of transient signal generation circuitry within the image sensor, monitoring circuitry may be used to capture and adjust transient signals as the signals are being transmitted. The transient signals may be voltage booster signals that are generated by booster circuitry to adjust row control signal levels to be below the ground reference voltage or above the supply reference voltage before providing them to the array of image sensor pixels. The captured and adjusted transient signals may be multiplexed and transmitted through a common buffer circuit. The method of shifting/adjusting the captured voltages may also apply to static signals. The multiplexed adjusted signals may be converted from digital signals to analog signals with digital-to-analog conversion circuitry. The digitized signals may be transmitted to host circuitry for processing which may include pass/fail testing.

Abstract: An imaging system with real-time digital testing capabilities verifies the functionality of image processing circuitry used to process pixel data signals read out from a pixel array during imaging operations. Image processing circuitry may process a data frame read from an imaging array that includes multiple regions of imaging and non-imaging data. Digital test patterns may be generated to test the functionality of specific image processing blocks. Test patterns may correspond to or represent imaging data or non-imaging data from regions of the output readout frame. A checksum generator generates a test pattern checksum for output of a subset of the image processing blocks that were provided with a given test pattern. The test pattern checksum may be compared to a predetermined checksum of the output of properly functioning image processing blocks provided with test patterns equivalent to the given test pattern.

Abstract: An imaging system with real-time digital testing capabilities verifies the functionality of image processing circuitry used to process pixel data signals read out from a pixel array during imaging operations. Image processing circuitry may process a data frame read from an imaging array that includes multiple regions of imaging and non-imaging data. Digital test patterns may be generated to test the functionality of specific image processing blocks. Test patterns may correspond to or represent imaging data or non-imaging data from regions of the output readout frame. A checksum generator generates a test pattern checksum for output of a subset of the image processing blocks that were provided with a given test pattern. The test pattern checksum may be compared to a predetermined checksum of the output of properly functioning image processing blocks provided with test patterns equivalent to the given test pattern.

Abstract: An image sensor with an array of pixels is provided. In order to determine failure of transient signal generation circuitry within the image sensor, monitoring circuitry may be used to capture and adjust transient signals as the signals are being transmitted. The transient signals may be voltage booster signals that are generated by booster circuitry to adjust row control signal levels to be below the ground reference voltage or above the supply reference voltage before providing them to the array of image sensor pixels. The captured and adjusted transient signals may be multiplexed and transmitted through a common buffer circuit. The method of shifting/adjusting the captured voltages may also apply to static signals. The multiplexed adjusted signals may be converted from digital signals to analog signals with digital-to-analog conversion circuitry. The digitized signals may be transmitted to host circuitry for processing which may include pass/fail testing.