发明名称 |
AUTOMATIC CLOCK DE-SKEWING ON A CIRCUIT BOARD |
摘要 |
Apparatus and method for providing automatic clock de-skewing for a plurality of circuit boards of a data processing system. In a preferred embodiment, each circuit board is of multi-layer construction and contains a clock distribution chip which includes on-chip automatic clock de-skewing circuitry for providing de-skewed clocks to other chips on the circuit board. In a preferred implementation of the clock de-skewing circuitry, feedback circuitry including a multi-tapped delay line and an accurate reference delay are employed in conjunction with a phase comparator for automatically providing de-skewed clocks at the clock ouputs of the clock distribution chip. The accurate reference delay is advantageously provided by a strip transmission line formed in a conductive layer of the multi-layer board containing the chips. In a preferred implementation of the method, a clock distribution chip includes on-chip automatic clock de-skewing circuitry requiring an accurate reference delay which is advantageously provided by a strip transmission line formed on one of the conductive planes of the multi-layer circuit board containing the chips. |
申请公布号 |
WO8900311(A1) |
申请公布日期 |
1989.01.12 |
申请号 |
WO1988US02060 |
申请日期 |
1988.06.20 |
申请人 |
UNISYS CORPORATION |
发明人 |
FLORA, LAURENCE, PAUL;MCCULLOUGH, MICHAEL, ANTHONY |
分类号 |
G06F1/10;H05K1/02;H05K3/42;(IPC1-7):G06F1/04 |
主分类号 |
G06F1/10 |
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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