Abstract: Each column of pixels in an image sensor array has at least two column bitlines connected to an output of each pixel. A readout input circuit includes first inputs and a second input. Each first input is connected, via a capacitance, to a comparator input node. The second input is connected via a capacitance to the same comparator input node. The first inputs receive, in parallel, an analog signal acquired from the pixels via the column bitlines. The analog signals vary during a pixel readout period and have a first level during a first calibration period and a second level during a second read period with the analog signals being constantly read onto the capacitances during both the first calibration period and the second read period. The comparator compares an average of the signals on the plurality of first inputs to the reference signal.

Abstract: A method for forming in monolithic form a DRAM-type memory, including the steps of forming, on a substrate, parallel strips including a lower insulating layer, a strongly-conductive layer, a single-crystal semiconductor layer, and an upper insulating layer; digging, perpendicularly to the strips, into the upper insulating layer and into a portion of the semiconductor layer, first and second parallel trenches, each first and second trench being shared by neighboring cells; forming, in each first trench, a first conductive line according to the strip width; forming, in each second trench, two second distinct parallel conductive lines, insulated from the peripheral layers; filling the first and second trenches with an insulating material; removing the remaining portions of the upper insulating layer; and depositing a conductive layer.