Patent ID: 8729451
Filing Date: 2014-05-20
Classification: H04N

Abstract:
1. A method of operating an image sensor, the method comprising: adjusting a capacitance coupled to a circuit node within a pixel cell, wherein the circuit node is coupled to selectively receive an image charge acquired by a photo-sensor of the pixel cell, wherein a conversion gain is selected from multiple conversion gains for the pixel cell by adjusting the capacitance; selecting a voltage level from multiple voltage levels for use as a reset signal when the reset signal is asserted, wherein the reset signal controls resetting of the circuit node during operation of the pixel cell and is applied to a gate terminal of a reset transistor, wherein the voltage level is selected dependent upon which of the multiple conversion gains is selected by adjusting the capacitance; asserting the reset signal to reset a voltage at the circuit node; acquiring an image charge at the photo-sensor; transferring the image charge to the circuit node thereby changing the voltage at the circuit node; and reading out image data indicative of the voltage at the circuit node.