Power supply noise suppression circuit, suppression method and image sensor

Abstract

The invention relates to a power supply noise suppression circuit and suppression method. The power supply noise suppression circuit comprises a pixel circuit, a mirror image power supply noise circuit and a comparator, an image signal of a first power supply noise signal of a power supply superposed in the pixel circuit is input into a first input end of the comparator, a comparison signal of a second power supply noise signal of the power supply superposed in the mirror image power supply noise circuit is input into a second input end of the comparator, and the amplitude of the second power supply noise signal is the same as that of the first power supply noise signal; and the mirror image power supply noise circuit comprises a mirror image circuit and a gain amplification circuit, the mirror image circuit is used for converting the noise voltage of the power supply into compensation current, and the gain amplification circuit is used for performing gain amplification on the compensation current and then converting the compensation current into voltage, and outputting the comparison signal to the second input end of the comparator. The power supply noise of the source electrode following transistor in the pixel circuit is suppressed through the power supply noise of the power supply in the mirror image power supply noise circuit, the power supply noise interference can be effectively resisted, the image noise is reduced, and the image quality is improved.

Description

technical field [0001] The invention relates to the field of image sensor electronic circuits, in particular to a power supply noise suppression circuit, a suppression method and an image sensor. Background technique [0002] Image sensors are commonly used in a variety of electronic devices, such as video surveillance systems, smart phones, digital cameras, and smart AI, face recognition, and other electronic products to capture and identify image information of people or scenes. As an important part of digital cameras, it provides the conversion of optical images into electrical signals. Image sensors can be divided into CMOS (Complementary Metaloxide Semiconductor, Complementary Metal Oxide Semiconductor), CCD (Charge Coupled Device, Charge Coupled Device) and image sensors according to different components. [0003] CMOS image sensors have the advantages of high integration, low power consumption, programmable random reading of local pixels, high speed and low cost, and...

AI Technical Summary

Problems solved by technology

If the output of the LDO is affected, the power supply noise will still be reflected on the image. Therefore, when using the LDO to solve the power supply noise, when the chip interference is large, the stabilization speed of this method is limited. During the stabilization process, the power supply noise is still It will be reflected on the image, and the LDO also occupies a large layout area, consumes power and limits the power supply used by other modules, which may lead to a decrease in the performance of the image sensor chip

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