Semiconductor Components Industries, LLC

Cornelis Daniel Hoekstra

Jeffery S Beck

Sergey Velichko

Ray Alan Mentzer

Dennis Robert Engelbrecht

Raymond Allen Davis

Frank James Demonte

An imaging system may include an image sensor having a pixel array. The pixel array may receive test signals from multiplexers located at the top or bottom of each column of the array. Test signals may be provided to each column based on a predefined test pattern. In some arrangements, pixel array photodiodes may receive test signals through an anti-blooming transistor while the anti-blooming transistor is on. In other arrangements, dark current of photodiodes in the pixel array may be modulated by voltages applied to the drain of an anti-blooming transistor while the anti-blooming transistor is off. In other arrangements, pixel array photodiodes may receive test signals through a reset transistor. Arbitrary test patterns may be applied to determine photodiode or floating diffusion node leakage and incorrect pixel control voltages. Arbitrary patterns may also be superimposed on light-based image data in the manner of a watermark.

Methods and apparatus for generating test and overlay patterns in image sensors

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.

Imaging systems and methods for transient signal integrity verification

An imager with error verification capabilities may include an array of pixels and an array of error detection circuits. The array of pixels may receive control signals that control the array of pixels to produce image pixel signals. The error detection circuits may receive the control signals and produce error detection signals. The image pixels and error detection signals may be conveyed over a readout path to image processing circuitry such as an external digital signal processor for detecting control signal errors. Each error detection circuit may be a modified copy of a corresponding pixel in the pixel array or may be a read only memory element. The array of error detection circuits may produce unique values that may be compared to expected values to detect whether correct control signals are provided to the pixel array for a given mode of operation.

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Corvalis, OR, United States of America

Cornelis Daniel Hoekstra