| 摘要 |
PROBLEM TO BE SOLVED: To provide an oscillator, wherein phase noise is reduced without narrowing an oscillation frequency variation range. SOLUTION: In the oscillator which comprises a bias circuit between a collector and a base of a bipolar transistor Tr1, an element or circuit such as e.g., a baseband choke coil 16 indicating sufficiently high impedance in a baseband frequency band lower than an oscillation frequency is connected between a power source Vcc and the collector. A noise signal in the baseband frequency band is negatively fed back via the bias circuit without being leaked to a power source side by the choke coil 16. In place of the choke coil 16, a current mirror circuit may be included. COPYRIGHT: (C)2009,JPO&INPIT
|
