| 摘要 |
PROBLEM TO BE SOLVED: To reduce costs required for measuring the range of oscillation frequencies of an oscillator embedded in an integrated circuit. SOLUTION: In the integrated circuit of this invention, frequency comparison is performed between output of the oscillator frequency-divided at a frequency-diving ratio M1 and a reference signal inputted to the integrated circuit from the outside to compare the oscillation frequencies of the oscillator, and comparison results are stored in a storage circuit A52 of the integrated circuit. After the dividing ratio is changed over to a dividing ratio M2, results of comparison between the oscillation frequencies of the oscillator and the reference signal are stored in a storage circuit B53. By reading the comparison results of the storage circuit A51 and the storage circuit B53 from a storage circuit output terminal 12 to outside the integrated circuit, the range of oscillation frequencies of the oscillator is measured. COPYRIGHT: (C)2006,JPO&NCIPI
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