| 摘要 |
A filter circuit which can automatically adjust a time constant is provided. A time constant of a filter circuit is adjusted by supplying, to the filter circuit, a control signal for controlling an oscillation circuit to output a signal of a predetermined frequency. Since the time constant of filter circuit is automatically adjusted, the adjusting work which hereto has been required for tuning filter circuits can be eliminated and thereby the manufacturing process of the filter circuit or semiconductor device can be simplified and the manufacturing time can be remarkably shortened.
|
