发明名称 |
Low-jitter loop filter for a phase-locked loop system |
摘要 |
A loop filter device and method for implementing a loop filter for a phase locked loop ("PLL") circuit, which locks a frequency of a signal to a reference frequency, are disclosed. The loop filter includes a proportional path circuit and an integral path circuit. The proportional path circuit receives a charge pump output and determines and holds a charge to be directed to or taken from a PLL circuit throughout an update period based on a detected phase difference for the update period for locking a frequency of a signal for a PLL circuit to a reference frequency. The integral path circuit is coupled to the proportional path circuit, and the integral path circuit receives another charge pump output and tracks a total charge level for the PLL circuit based on phase differences for present and prior update periods.
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申请公布号 |
US2003128074(A1) |
申请公布日期 |
2003.07.10 |
申请号 |
US20020043558 |
申请日期 |
2002.01.10 |
申请人 |
MAXIM ADRIAN;SCOTT BAKER;SCHNEIDER EDMUND M.;HAGGE MELVIN L. |
发明人 |
MAXIM ADRIAN;SCOTT BAKER;SCHNEIDER EDMUND M.;HAGGE MELVIN L. |
分类号 |
H03L7/093;H03L7/089;H03L7/18;(IPC1-7):H03L7/00 |
主分类号 |
H03L7/093 |
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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