摘要 |
An anti-blooming charge accumulation pixel using an anti-blooming element coupled to the pixel prevents blooming by ensuring that a voltage of a charge accumulation device of the pixel is always returned to a clamping voltage following comparison events. The anti-blooming element is used to return the voltage across a photodiode to the supply voltage when both a low voltage comparison and a high voltage comparison have occurred. A control block is used to determine an input signal to the anti-blooming element based upon the result of a low voltage comparison and a high voltage comparison. The input signal can be used to drive the anti-blooming element to a desired logic level, thereby causing the voltage across the charge accumulation device to be the clamping voltage. The use of the anti-blooming element eliminates blooming to adjacent pixels, independent of an integration time of the pixel.
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