Patent ID: 8189082
Filing Date: 2012-05-29
Classification: H04N

Abstract:
1. A signal processing apparatus that generates a voltage signal corresponding to electric charges accumulated in a photodiode in a pixel cell in a correlated double sampling process, wherein the signal processing apparatus comprises: a floating diffusion (FD) for converting the accumulated electric charges to a voltage signal; and a transistor in which a gate terminal is connected to the FD and a source terminal is connected to an output signal line, and when the FD is reset in the correlated double sampling process, a power supply voltage is applied to the FD for a predetermined period to set a voltage of the output signal line as a first voltage, and thereafter, the set voltage of the output signal line is set as a second voltage higher than the first voltage, and as a configuration for controlling the set voltage of the output signal line, the signal processing apparatus comprises: a load transistor in which a bias voltage is input to a gate terminal and a drain terminal is connected to the output signal line; and a switching transistor serially connected to the load transistor, in which a source terminal is connected to a reference potential point, and in a reset process of the FD, a power supply voltage is applied to the FD for a predetermined period in a state that the switching transistor is turned on and the bias voltage is set as a first bias voltage to turn on the load transistor, thereby setting the set voltage of the output signal line as the first voltage, and thereafter, the bias voltage is set as a second bias voltage lower than the first bias voltage and capable of maintaining an on state of the load transistor in a state that the switching transistor is turned on, thereby setting the set voltage of the output signal line as the second voltage.