| 摘要 |
PURPOSE:To prevent the overlapping of smearing signals, by providing an overflow Drain, which discharges extra signal charge, at the lower side of a horizontal CCD channel. CONSTITUTION:When extra signal charge is discharged into a drain 9, voltages phiH1H and phiH2H are applied to horizontal transfer gates 1 and 2. The extra signal charge is transferred to a horizontal transfer channels from vertical transfer channels. When the signal charge is excessive, the charge exceeds the capacity of the horizontal transfer channels. A drain voltage VD is applied to the drain 9 so as to absorb the excessive signal charge into the drain 9 through a counterstroke layer 8 having a reverse conductivity type with respect to the channel. Finally, the extra signal charge still remaining in the horizontal CCD is transferred to an output part as a dummy signal. Thus the overlapping of smearing signals can be prevented. |
