| 摘要 |
PURPOSE:To prevent the generation of noises of a fixed pattern due to a clock field through by lowering the driving ability of a control signal driving circuit and making the descending time of a driving wave shape longer than a time (time constant of wiring) determined by the product of a whole resistance and a whole capacity of the wiring. CONSTITUTION:The descending time of a control signal produced from a control circuit 2 is made longer to suppress the generation of a fixed pattern noise. Namely, by making the descending time longer than a time determined by the product of a whole resistance and a whole capacity of a wiring, there is a scarce difference in the descending time between a switch (1-1-1) near to the control circuit 2 and a switch (1-n-1) remote from the circuit 2. Therefore, the clock field through error becomes even and the fixed pattern noise is hardly produced. As a method for making the descending time of a control signal longer, there is a one that the length L, of the channel of a driver transistor is made long to make W/L small. |
