发明名称 |
CIRCUIT FOR COMPENSATING LPF CAPACITOR CHARGE LEAKAGE IN PHASE LOCKED LOOP SYSTEMS |
摘要 |
The present invention provides for a low pass filter. A first capacitor, has a first associated leakage current. A second capacitor has a specified capacitance that is a fraction of the capacitance of the first capacitor, the second capacitor further having a second associated leakage current. A voltage follower circuit is coupled to the output of the first and second capacitor. First and second current sources are coupled to the voltage follower circuit. A bias current source is coupled the first current source. A current mirror is coupled to the second current source, and the current mirror is further coupled to at least the anode of the first capacitor, thereby generating replacement current of a capacitor within a low-pass filter.
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申请公布号 |
US2005248376(A1) |
申请公布日期 |
2005.11.10 |
申请号 |
US20040840562 |
申请日期 |
2004.05.06 |
申请人 |
INTERNATIONAL BUSINESS MACHINES CORPORATION |
发明人 |
BOERSTLER DAVID W.;HAILU ESKINDER |
分类号 |
H03L7/00;H03L7/06;H03L7/089;H03L7/093;(IPC1-7):H03L7/06 |
主分类号 |
H03L7/00 |
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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