An electronic circuit includes image acquisition cells, wherein each cell has a photodetector coupled to a first node of the cell, and an amplifying transistor having a gate connected to the first node, a conduction node coupled to an output of the cell, and a node for controlling a back gate voltage. The amplifying transistor is configured so that its threshold voltage varies according to the back gate voltage. A control circuit adjusts a voltage applied to the control node of the back gate voltage of the amplifying transistor of one of the cells according to a comparison of the voltage present at the cell output and a reference voltage.