Patent ID: 6653992
Filing Date: 2003-11-25
Classification: H04N

Abstract:
A circuit for reducing correlated noise in an imager having a plurality of detection elements, the circuit comprising:a first differential amplifier (110a, 310) comprising a first amplifier output (200a, 312), a first amplifier input line (116a, 314) and a first amplifier reference line (210a, 304), the first amplifier input line (116a, 314) receiving first input signals from a first imager detection element (106a), the first amplifier reference line (210a, 304) receiving a first reference input; a first switching element (108a) controlling transmission of the first input signals from the first imager detection element (106a) to the first differential amplifier (110a, 310); a second differential amplifier (110b, 310) comprising a second amplifier output (200b, 312), a second amplifier input line (116b, 314) and a second amplifier reference line (210b, 304), the second amplifier input line (116b, 314) receiving input signals from a second imager detection element (106b), the second amplifier reference line (210b, 304) receiving a second reference input; a second switching element (108b) controlling transmission of the second input signals from the second imager detection element (106b) to the second differential amplifier (110b, 310); the circuit configurable to sample the first amplifier output (200a, 312) and the second amplifier output (200b, 312) in a correlated manner; an array voltage source (122, 300) supplying a first common voltage used at the first and second imager detection elements (106a, 106b); a switch voltage source (112, 302) supplying a second common voltage used for switching the first and second switching elements (108a, 108b); a first capacitance component (308) located between the array voltage source (122, 300) and the first and second amplifier reference lines (210, 304); and a second capacitance component (306) located between the switch voltage source (112, 302) and the first and second amplifier reference lines (210, 304).