PIXEL CIRCUIT HAVING A BOOSTING CAPACITOR, DRIVING METHOD OF THE PIXEL CIRCUIT AND IMAGE SENSOR COMPRISING THE PIXEL CIRCUIT

摘要

A pixel circuit having a boosting capacitor, a method for driving the pixel circuit, and an image sensor including the pixel circuit are provided to improve the rate of photocharge transfer from a photodiode to a floating diffusion node by boosting the voltage of the floating diffusion node to a voltage higher than a power supply voltage by using the boosting capacitor. A pixel circuit includes a photodiode(PD), a transfer transistor(TTr), a reset transistor(RTr), a signal output unit(302), and a boosting capacitor(Cb). The photodiode generates photocharges corresponding to incident light. The transfer transistor transfers the photocharges to a floating diffusion node(FDN) in response to a transfer control signal. The reset transistor transfers a power supply voltage to the floating diffusion node in response to a reset control signal. The signal output unit outputs a voltage signal corresponding to the voltage of the floating diffusion node in response to a select control signal. The boosting capacitor is connected between the gate of the transfer transistor and the floating diffusion node.