发明名称 |
Dynamically adjustable termination impedance control techniques |
摘要 |
The on-chip impedance termination circuits can be dynamically adjusted to match transmission line impedance values. A network of termination resistors on an integrated circuit provides termination impedance to a transmission line coupled to an IO pin. The termination resistors are coupled in series and in parallel with each other. Pass gates are coupled to the resistors. The pass gates are individually turned ON or OFF to couple or decouple resistors from the transmission line. Each pass gate is set to be ON or OFF to provide a selected termination resistance value to the transmission line. The termination resistance of the resistor network can be increased or decreased to match the impedance of different transmission lines. The termination resistance can also be varied to compensate for changes in the resistors caused by temperature variations on the integrated circuit or other factors.
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申请公布号 |
US6888370(B1) |
申请公布日期 |
2005.05.03 |
申请号 |
US20030645932 |
申请日期 |
2003.08.20 |
申请人 |
ALTERA CORPORATION |
发明人 |
LUO MEI;WONG WILSON;SHUMARAYEV SERGEY |
分类号 |
H03K19/0175;H04L25/02;(IPC1-7):H03K19/017 |
主分类号 |
H03K19/0175 |
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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