| 摘要 |
<P>PROBLEM TO BE SOLVED: To rapidly calculate a clamp voltage so as to match a black level to a target value. <P>SOLUTION: An A/D clamp circuit 102 calculates a clamp voltage corresponding to a target value of a black level read out from a shading pixel, by extrapolating a relation of an A/D conversion value of the black level and the clamp voltage, read from the shading pixel when a predetermined clamp voltage is applied, and gives the relation of the A/D conversion value of the black level and the clamp voltage read from the shading pixel by a linear function and applies two or more clamp voltages as a predetermined clamp voltage. A reference voltage is switched to a clamp voltage generation period and a ramp wave generation period by time division. An ADC circuit performs A/D conversion of a signal component based on a count result of a clock in which the level of signal component matches to the level of ramp wave in the ramp wave generation period. <P>COPYRIGHT: (C)2013,JPO&INPIT |
