| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an automatic adjustment oscillator capable of enhancing accuracy of an output frequency without using a charge pump. <P>SOLUTION: An oscillator 10 has an oscillation circuit 11, a first voltage-supplying circuit 13, a second voltage-supplying circuit 14, and an adjusting value-generating circuit 16. The first voltage-supplying circuit 13 has a resistor R1 with a resistance value and a capacitor C1 with a capacitance by which a time constant that brings a first voltage V1 to a reference voltage Vref in a reference time period can be obtained. The second voltage-supplying circuit 14 raises a second voltage V2 by first and second switching means SW1 and SW2 that carry out switching by pulse signals S1 and S2 depending on the frequency of the oscillation circuit 11. When the second voltage V2 becomes the reference voltage Vref prior to the first voltage V1, the adjusting value-generating circuit 16 supplies an adjusting value that reduces the frequency to the oscillation circuit 11. Meanwhile, when the second voltage V2 becomes the reference voltage Vref later than the first voltage V1, the adjusting value-generating circuit 16 supplies an adjusting value that raises the frequency to the oscillation circuit 11. <P>COPYRIGHT: (C)2011,JPO&INPIT |
