Patent ID: 7667746
Filing Date: 2010-02-23
Classification: H04N

Abstract:
1. An apparatus for delaying a sampling signal used to sample pixels in an image sensor device, the apparatus comprising: a controller configured to receive input relating to a length of time by which an input sampling signal is to be delayed and to produce a delay length selection signal that is based on the received input; and a delay circuit configured to receive the delay length selection signal from the controller and to delay an input sampling signal by a selected length of time based on the delay length selection signal to produce a delayed sampling signal; wherein the delay circuit comprises a current source that produces an electrical current I at least one capacitor having a first terminal connected to a charging node and a second terminal connected to ground; at least one switch connected between ground and the charging node, said at least one switch being turned on or off by the delay length selection signal, wherein when said at least one switch is turned off, said at least one capacitor charges thereby causing the voltage level on the charging node to increase, and wherein when said at least one switch is turned on, said at least one capacitor discharges to ground thereby causing the voltage level on the charging node to decrease; and a latch having an input connected to the charging node and an output for outputting the delayed sampling signal, the latch having a triggering threshold level such that when the voltage level on the charging node reaches the threshold level of the latch, the latch outputs the delayed sampling signal.