Pixel-circuit supply noise cancellation

A method for operating a pixel circuit of an imaging sensor, the method comprising:

• generating, by a photodiode, electrical charges at a floating diffusion FD0 of a front-end circuit as a photodiode voltage, wherein the front-end circuit is coupled to a supply voltage PIXVDD, and wherein the supply voltage PIXVDD includes a voltage noise component;
• transferring the photodiode voltage to a common floating diffusion FDC of a signal storage circuit that is coupled to the front-end circuit, wherein the photodiode voltage is transferred as a common floating diffusion voltage of the signal storage circuit, and wherein the common floating diffusion voltage includes the voltage noise component of the supply voltage PIXVDD;
• generating, by a unity gain circuit, a control voltage VCTRL as an output voltage of the unity gain circuit, wherein the control voltage VCTRL includes the voltage noise component of the supply voltage PIXVDD, and wherein the unity gain circuit is coupled to the signal storage circuit;
• storing, by the signal storage circuit, a reference voltage VR, wherein the reference voltage VR includes the voltage noise component of the supply voltage PIXVDD;
• storing, by the signal storage circuit, a signal voltage VS, wherein the signal voltage VS includes the voltage noise component of the supply voltage PIXVDD, and wherein the signal voltage VS corresponds to the common floating diffusion voltage;
• and
• outputting the signal voltage VS by an output circuit that is coupled to the signal storage circuit.