Method and system for testing image sensor system-on-chip
View Patent ↗Methods and systems for testing an image sensor system-on-chip (SOC). For testing an image sensor SOC that integrates a sensor array and an image processing component, defects are being searched separately in the sensor array and the image processing component in order to isolate possible defects of the sensor array from the possible defects of the image processing component. In so doing, the location of the defects can be pin-pointed.
1. A method for locating defect in an image sensor system-on-chip (SOC) that integrates an image sensor array and an image processing circuit component, said method comprising the steps of:
a) having a image sensor array test output formed on said image sensor system-on-chip(SOC) and coupled to a test system;
b) identifying defect to said sensor array independent of said image processing circuit by feeding a plurality of test images to said sensor array to generate therefrom output data on said image sensor array test output;
c) comparing said output data to a plurality of reference data representing defect-free output of said sensor array;
d) characterizing analog nature of said image sensor array for establishing an allowable level of discrepancy; and
e) in response to a difference uncovered from comparing said output data to said reference data, determining location and type of defect in said image sensor array using said uncovered data difference if said difference is greater than said allowable level of discrepancy.
2. The method of claim 1 , wherein said sensor array comprises:
a sensor; and
an analog-to-digital converter (ADC) coupled to said sensor.
3. The method of claim 1 , wherein said image processing circuit component comprises:
a color processing circuit component adapted to color process said output image data from said image sensor array;
a compression engine coupled to said color processing circuit component adapted to compressed said color processed image data; and
a transceiver coupled to said color processing circuit component, said transceiver adapted to transfer said compressed image data out of said SOC.
4. A method for locating defect in an image sensor system-on-chip (SOC) that integrates an image sensor array and an image processing circuit component, said method comprising the steps of:
a) having an image processing test input formed on said image sensor system-on-chip (SOC) and coupled to a test system;
b) Simulating defect-free operation of said image processing component for preparing a plurality of simulated image processed data using said test system;
c) identifying defect to said image processing component independent of said image sensor array by directly feeding a plurality of test data to said image processing test input to generate therefrom plurality of outputs that is compared with said ((a)) plurality of simulated image processed data representing defect-free output of said image processing circuit component;
d) comparing said plurality of outputs with said plurality of simulated image processed reference data; and
e) in response to said plurality of outputs being found different from said plurality of simulated image processed data, indicating location and type of defect of said image processing component.
5. The method of claim 4 , wherein said sensor array comprises:
a sensor; and
an analog-to-digital converter (ADC) coupled to said sensor.
6. The method of claim 4 , wherein said image processing circuit component comprises:
a color processing circuit component adapted to color process said output image data from said image sensor array;
a compression engine coupled to said color processing circuit component adapted to compressed said color processed image data; and
a transceiver coupled to said color processing circuit component, said transceiver adapted to transfer said compressed image data out of said SOC.
7. A method for locating defect in an image sensor system-on-chip (SOC) that integrates an image sensor array and image processing circuit component, said method comprising the steps of:
a) having an image input on a test system and coupled to said image sensor system-on-chip (SOC);
b) Simulating defect-free operation of said image sensor system-on-chip (SOC) for preparing a plurality of reference data by feeding a plurality of test images to said image input on said test system;
c) characterizing analog nature of said image sensor array for establishing an allowable level of discrepancy;
d) identifying defect to the coupling between said image sensor array and said image processing circuit component by feeding said ((a)) plurality of test images to said sensor array for generating from said image processing component an output of image processed data;
e) comparing said image processed data with ((a)) said plurality of reference data representing defect-free output of said SOC; and
f) in response to a difference found between said output of image processed data and said plurality of reference data, indicating location and type of defect of said coupling between said sensor and said image processing component if said difference is greater than said allowable level of discrepancy.
8. The method of claim 7 , wherein said sensor array comprises:
a sensor; and
an analog-to-digital converter (ADC) coupled to said sensor.
9. The method of claim 7 , wherein said image processing circuit component comprises:
a color processing circuit component adapted to color process said output image data from said image sensor array;
a compression engine coupled to said color processing circuit component adapted to compressed said color processed image data; and
a transceiver coupled to said color processing circuit component, said transceiver adapted to transfer said compressed image data out of said SOC.
10. A machine for detecting defect in an image sensor system-on-chip (SOC) that integrates an image sensor array and image processing circuit components, said machine comprises:
a transceiver adapted to couple to said image sensor array for intercepting output data resulting from said image sensor array operating on test images; and
a processing system coupled to said transceiver, said processing system adapted to generate reference data by simulating said image sensor array operating defect-free on said test images, said processing system adapted to characterize analog nature of said image sensor array for establishing an allowable level of discrepancy by different processing runs of said image sensor system-on-chip (SOC), wherein the difference between said output data and said reference data is adapted to indicate defect of said image sensor array if said difference is greater than said allowable level of discrepancy.
11. The machine of claim 10 , wherein said test images are a computer generated test image pattern.
12. The machine of claim 10 , wherein said test images are live images.
13. The machine of claim 10 , wherein said sensor array comprises:
a sensor; and
an analog-to-digital converter (ADC) coupled to said sensor.
14. The machine of claim 10 , wherein said image processing circuit component comprises:
a color processing circuit component adapted to color process said output image data from said image sensor array;
a compression engine coupled to said color processing circuit component adapted to compressed said color processed image data; and
a transceiver coupled to said color processing circuit component, said transceiver adapted to transfer said compressed image data out of said SOC.
15. A machine for detecting defect in an image sensor system-on-chip (SOC) that integrates an image sensor array and image processing circuit components, said machine comprises:
a transceiver adapted to couple to said image processing component for bypassing said image sensor array and sending test data to said image processing component to be transformed into image processed data adapted to be fed back to said machine;
a processing system coupled to said transceiver, said processing system adapted to generate reference data by simulating said image processing component operating defect-free on said test data, wherein the difference between said image processed data and said reference data is adapted to indicate defect of said image processing component.
16. The machine of claim 15 , wherein said test images are a computer generated test image pattern.
17. The machine of claim 15 , wherein said test images are live images.
18. The machine of claim 15 , wherein said sensor array comprises:
a sensor; and
an analog-to-digital converter (ADC) coupled to said sensor.
19. The machine of claim 15 , wherein said image processing circuit component comprises:
a color processing circuit component adapted to color process said output image data from said image sensor array;
a compression engine coupled to said color processing circuit component adapted to compressed said color processed image data; and
a transceiver coupled to said color processing circuit component, said transceiver adapted to transfer said compressed image data out of said SOC.
20. A machine for detecting defect in an image sensor system-on-chip (SOC) that integrates an image sensor array and image processing circuit components, said machine comprises:
a transceiver adapted to couple to said image sensor array for receiving test images that are also fed to said image sensor array, said transceiver adapted to couple to said image processing circuit component for receiving image processed data from said image processing circuit component; and
a processing system coupled to said transceiver for receiving said test images, said processing system adapted to generate reference data by simulating said SOC operating defect-free on said test images, said processing system adapted to characterize analog nature of said image sensor array for establishing an allowable level of discrepancy by different processing runs of said image sensor system-on-chip (SOC), wherein the difference between said image processed data and said reference data is adapted to indicate defect of the coupling between said sensor array and said image processing circuit component if said difference is greater than an allowable level.
21. The machine of claim 20 , wherein said test images are a computer generated test image pattern.
22. The machine of claim 20 , wherein said test images are live images.
23. The machine of claim 20 , wherein said sensor array comprises:
a sensor; and
an analog-to-digital converter (ADC) coupled to said sensor.
24. The machine of claim 20 , wherein said image processing circuit component comprises:
a color processing circuit component adapted to color process said output image data from said image sensor array;
a compression engine coupled to said color processing circuit component adapted to compressed said color processed image data; and
a transceiver coupled to said color processing circuit component, said transceiver adapted to transfer said compressed image data out of said SOC.