Patent ID: 7277129

Claim:
An image sensor, comprising: a plurality of pixels, each pixel including, a sense node, a first device, connected to the sense node, that produces a signal at the sense node that is proportional to incident light intensity at the pixel, an output node, at least one select node connected to receive a first select signal for selecting said pixel output node from said plurality of pixels, a reset device connected for resetting said pixel, and a sample and hold circuit including a sample node coupled to said sense node, wherein said sample and hold circuit comprises a capacitor and a first switch; at least one amplifier, each amplifier including, a first input node connected to receive an output signal from the output node of a selected pixel, a second input node connected to a reference voltage source provided as a reference to reset a selected pixel, and an amplifier output node connected to couple an amplifier output signal to said sample and hold circuit of a selected pixel; a second select node connected to receive a second select signal for coupling said output signal of said amplifier to said sample and hold circuit of the selected pixel; and a second switch coupled, in series, between said sample and hold circuit and said amplifier output node to provide the amplifier output signal from said amplifier output node, through said second switch, to said sample and hold circuit.