发明名称 |
Frequency synthesizer having a speed-up circuit |
摘要 |
It is an object of the present invention to provide a frequency synthesiser with a lock speed-up arrangement in a simple and effective form. In accordance with the invention there is provided a frequency synthesiser including a voltage controlled oscillator, a phase detector which receives a base frequency signal and a feedback signal derived from the output of the voltage controlled oscillator and a filter circuit connecting the output of phase detector to a frequency control voltage input of the voltage controlled oscillator, the filter circuit having a reference voltage connection, and a speed-up circuit for applying a voltage signal to the reference voltage connection when a frequency change is demanded.
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申请公布号 |
US5963100(A) |
申请公布日期 |
1999.10.05 |
申请号 |
US19980028818 |
申请日期 |
1998.02.24 |
申请人 |
NEC CORPORATION |
发明人 |
TOLSON, NIGEL;CLARK, JUSTIN |
分类号 |
H03L7/187;H03L7/189;(IPC1-7):H03L7/10;H03L7/18 |
主分类号 |
H03L7/187 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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