| 摘要 |
PURPOSE:To provide a clock signal generating circuit in which a dot clock used to control a system with a simple digital circuit without employing a complicated analog circuit technology and making the system expensive in the system superimposing a picture generated from the graphic system onto a video signal. CONSTITUTION:The circuit generating a clock signal 7 by frequency-dividing a reference clock signal 4 starts the generation of the clock signal 7 by using an external control signal 11 as a trigger and is provided with another frequency divider circuit 3 starting the generation of the clock signal 7 by using an external control signal 11 and frequency-dividing the generated clock signal 7, and when the frequency divider circuit 3 generates the clocks by a prescribed clock number, the application of the reference clock 4 to the clock frequency divider circuit 2 is controlled to stop the clock output. |
