Back to results
US 7,804,052 B2Granted
Methods and apparatuses for pixel testing
AssigneeAptina Imaging Corporation
InventorKalairaja Chinnaveerappan
Life of this patent
Estimating the term…
Abstract
Methods and apparatuses for non-optical testing of imaging devices having an array of pixels are provided. One or more pixels are tested by setting the photoconversion device and/or a floating diffusion region to a known voltage level that is different from that used to operate the pixel during non-test operation. The pixel is then sampled and compared to an expected value.
Claims27
An imaging device comprising:
- an array of pixels, each pixel having a photoconversion device and a floating diffusion region;
- a power supply configured to supply a pixel voltage;
- and
- test circuitry configured to:
- set the pixel voltage to a predetermined test voltage;
- apply the test voltage to the photoconversion device and the floating diffusion region of at least one pixel;
- set the pixel voltage to an operating voltage, wherein the operating voltage is different than the test voltage;
- and
- read out a first and second test signals from the at least one pixel when the pixel voltage is at the operating voltage, the first test signal representing a voltage level of the floating diffusion region and the second test signal representing a voltage level of the photoconversion device.
6 more elements
A processor system comprising:
- a processor;
- and
- an imaging device coupled to the processor, the imaging device comprising:
- an array of pixels, each pixel having a photoconversion device and a floating diffusion region;
- a power supply configured to supply a pixel voltage;
- and
- testing circuitry configured to:
- set the pixel voltage to a predetermined test voltage;
- apply the test voltage to the photoconversion device and the floating diffusion region;
- set the pixel voltage to an operating voltage, wherein the operating voltage is different than the test voltage;
- read out first and second test signals from the pixel, the first test signal representing a voltage level of the floating diffusion region and the second test signal representing a voltage level of the photoconversion device;
- and
- process the test first and second test signals.
10 more elements
A method of testing an imaging device, the method comprising:
- performing a testing operation on at least a portion of the pixels of a pixel array, for each pixel tested, the testing operation comprising:
- applying a predetermined test voltage to a photoconversion device and a floating diffusion region;
- and
- reading out first and second test signals from the pixel, the first test signal representing a voltage on the floating diffusion region, the second test signal representing a voltage on the photoconversion device.
1 more element
A method of performing a testing operation on a pixel, the method comprising:
- providing a pixel having a photoconversion device and a floating diffusion region;
- applying a first test voltage to the photoconversion device and a second test voltage to the floating diffusion region;
- reading out a first test signal from the pixel representing a voltage on the floating diffusion region;
- reading out a second test signal from the pixel representing a voltage on the photoconversion device;
- and
- applying a predetermined criteria to the first and second test signals.
3 more elements
Dependencies are inferred from the claim text.