Image sensors with reduced fixed pattern noise

An imaging system, comprising:

• an image sensor comprising an array of pixels arranged in rows and columns;
• column lines coupled to the columns of the array of pixels, wherein signals from the array of pixels are configured to be read out over the column lines;
• sample and hold circuitry coupled to the column lines, wherein the sample and hold circuitry comprises at least three capacitors configured to store the signals and reset values for each of the column lines;
• and
• sample and hold control circuitry coupled to the sample and hold circuitry, wherein the sample and hold circuitry is configured to randomize a pattern in which the at least three capacitors are used to store the signals and the reset values on a frame-by-frame basis.

A method of operating an image sensor comprising an array of pixels arranged in rows and columns, the method comprising:

• reading out signals from a given column of the array of pixels with the rows of the given column randomized;
• sampling and holding the signals;
• storing the signals in column memory banks;
• and
• reading out the signals from the column memory banks with the rows of the given column de-randomized.