| 摘要 |
<p>PROBLEM TO BE SOLVED: To reduce the cost of an AGC circuit by increasing a constant current only when necessary and reducing a pull-in time. SOLUTION: In addition to a first comparator circuit 3, a second comparator circuit 4 for outputting only when the sample voltage of a ramp wave differs from its reference voltage by more than a specified value is provided, and an adjustment capability of the first comparator circuit is increased by adding the output of the second comparator circuit 4 to an operation current source of the first comparator circuit 3. As it is made possible to increase a pull-in capability by the second comparator circuit 4 only when necessary, it is possible to reduce the pull-in time of a ramp wave generation circuit at the time of supplying power or the like.</p> |
