This application claims the benefit of and claims priority to Indian Patent Application No. 201911035058, filed on Aug. 30, 2019, which is hereby incorporated by reference herein in its entirety.

BACKGROUND

This relates generally to imaging devices, and more particularly, to readout circuitry in image sensors.

Image sensors are commonly used in electronic devices such as cellular telephones, cameras, and computers to capture images. In a typical arrangement, an image sensor includes an array of image pixels arranged in pixel rows and pixel columns. Circuitry may be coupled to each pixel column for reading out image signals from the image pixels.

Typically, each image pixel contains a photodiode for generating charge in response to incident light. Each image pixel can generate charge in varying light conditions, such as in a relatively low light condition or in a relatively high light condition. As such, in some applications, it may be desirable for the image pixel generate signals that optimize for these varying light conditions, e.g., a low light signal and a high light signal. Additionally, the differing characteristics between the low light signal and the high light signal (e.g., the different types of dominant noise between the low light signal and the high light signal) may provide an opportunity to more efficiently adjust and configure readout circuitry for reading out each of these two signals.

It would therefore be desirable to provide imaging systems with improved readout circuitry (e.g., for reading out the low light signal with low read noise and higher settling accuracy, for reading out the high light signal more quickly while lowering power consumption).

