| 摘要 |
<P>PROBLEM TO BE SOLVED: To secure a sufficiently high AD-conversion processing speed and achieve digital values whose continuity is secured. <P>SOLUTION: A solid-state image pickup device comprises: pixels; vertical signal lines; an upper level AD conversion circuit; a lower level AD conversion circuit; a first selecting circuit; and a second selecting circuit. The first selecting circuit selects one of the vertical signal lines and outputs the voltage of the selected vertical signal line in a normal mode while outputting a correction voltage in a correction mode. The upper level AD conversion circuit calculates residual voltages of 2<SP POS="POST">M</SP>corresponding to the differences between the signal voltage based on the output of the first selecting circuit and threshold voltages of 2<SP POS="POST">M</SP>. In the normal mode, the upper AD conversion circuit outputs the digital value of a high-order bit corresponding to the maximum threshold voltage out of the threshold voltages of 2<SP POS="POST">M</SP>which does not exceed the signal voltage, and also outputs the residual voltage corresponding to the maximum threshold voltage. In the correction mode, the upper AD conversion circuit outputs the residual voltage corresponding to any one selected threshold voltage of the threshold voltages of 2<SP POS="POST">M</SP>. <P>COPYRIGHT: (C)2012,JPO&INPIT |
