| 摘要 |
PROBLEM TO BE SOLVED: To solve a problem that a jitter characteristic caused by a power supply noiseΔV can not be improved even by using a differential circuit having a high resistance to the noise. SOLUTION: A crystal oscillator circuit is provided with a first terminal (X1) and a second terminal (X2) to connect a crystal oscillator (X0), a first amplification circuit (1), and a second amplification circuit (2). The first amplification circuit (1) connects an input to the first terminal (X1/OUT1) and connects an output to the second terminal (X2/OUT2). The second amplification circuit connects the input to the second terminal (X2/OUT2) and connects the output to the first terminal (X1/OUT1). The crystal oscillator circuit makes the first terminal (X1/OUT1) and the second terminal (X2/OUT2) be differential output nodes. The crystal oscillator circuit is constituted so that a ratio of an impedance watching a positive power supply (VCC) and a negative power supply (VSS) from the first terminal (X1/OUT1) and the ratio of the impedance watching the positive power supply (VCC) and the negative power supply (VSS) from the second terminal (X2/OUT2) become equal. COPYRIGHT: (C)2007,JPO&INPIT
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