| 摘要 |
PURPOSE:To obtain an oscillating circuit changing an oscillating frequency at a prescribed step width by selecting plural dividing capacitors weighted in response to a setting code to constitute the oscillating circuit. CONSTITUTION:A time constant circuit for deciding a frequency of the oscillating circuit 6 consists of a split capacitor 1, a coil 6 and a trimmer capacitor 5, capacitors C1-Cn of a split capacitor 15 are weighted in terms of binary (2<n>) number and they are selected by transmitting an output of a binary counter 3 to a switch circuit 2. Thus, in setting a numeral to the binary counter 3, an optical frequency is obtained by a prescribed step width. The split capacitor 1 consists of lines weighted in terms of binary code opposite to ground lines. |
