The present invention relates to a fault detection circuit for detecting one or more column faults in a pixel array of an image sensor. The present invention further relates to a readout circuit for reading out a column line of an image sensor, and to an image sensor comprising the same.
The fault detection circuit according to the invention comprises a signal unit for applying an electrical signal to a given column line of the pixel array, a determining unit for measuring a response to the applied electrical signal and for determining whether a fault exists for said given column line in dependence of the measured response, and a controller for controlling the signal unit and the determining unit, and for outputting a fault status for said given column line.