发明授权
- 专利标题: Phase-locked loop with dual-mode phase/frequency detection
- 专利标题(中): 具有双模相位/频率检测的锁相环
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申请号: US10107359申请日: 2002-03-28
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公开(公告)号: US06759838B2公开(公告)日: 2004-07-06
- 发明人: Kuang-Chung Tao , Chi-Ming Hsiao , Chang-Fu Kuo
- 申请人: Kuang-Chung Tao , Chi-Ming Hsiao , Chang-Fu Kuo
- 优先权: TW90110228A 20010427
- 主分类号: G01R2312
- IPC分类号: G01R2312
摘要:
A phase-locked loop with dual-mode phase/frequency detection is provided. The phase-locked loop circuit includes a dual-mode phase/frequency detector, a loop filter, a voltage-controlled oscillator, and a frequency converter. In addition, the dual-mode phase/frequency detector includes a digital phase/frequency detector, an analog phase/frequency detector, a charge pump, and a control unit. When the phase-locked loop circuit starts, the control unit causes a detection output signal from the dual-mode phase/frequency detector to correspond to a digital signal from the digital phase/frequency detector. When the phase-locked loop circuit approaches a lock state, the control unit causes the detection output signal to correspond to an analog signal from the analog phase/frequency detector. The phase-locked loop with dual-mode phase/frequency detection has the advantages of providing linear characteristics, fast switching speed, and high sensitivity.