发明名称 |
Digitally controlled crystal oscillator with integrated coarse and fine control |
摘要 |
A method of tuning a DCXO includes the step of providing a coarse tuning array and a fine tuning array of capacitors fabricated on the same integrated circuit die. The coarse array is adjusted until the difference between a desired frequency and the output frequency corresponds to a change in capacitance no greater than half the range of the fine tuning array. In one embodiment, the fine tuning array is adjusted to mid-range before adjusting the coarse tuning array. A DCXO apparatus includes at least one integrated circuit segmented switched capacitor network providing a capacitance that is a nonmonotonic function of a composite input code. The segmented switched capacitor network includes parallel coupled binary weighted and thermometer coded switched capacitor networks for coarse and fine tuning, respectively.
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申请公布号 |
US2003206070(A1) |
申请公布日期 |
2003.11.06 |
申请号 |
US20020138027 |
申请日期 |
2002.05.03 |
申请人 |
PIETRUSZYNSKI DAVID M.;FREY DOUGLAS R. |
发明人 |
PIETRUSZYNSKI DAVID M.;FREY DOUGLAS R. |
分类号 |
H03B1/00;H03B5/32;H03K3/03;H03L7/099;(IPC1-7):H03B5/32 |
主分类号 |
H03B1/00 |
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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