摘要 |
The length of the phase lock feedback path of the phase lock loop chip (PLL chip) is adjusted so that the timing of clock pulses at computer chips is measured relative to the arrival time of a clock pulse at the computer board clock pin. This adjustment of the length of the phase lock loop accounts for the length of the trace from the computer board clock pin to the PLL clock input pin. This adjustment of the length of the phase lock loop removes uncertainty between vendors in the arrival time of clock pulses at the computer chips, relative to arrival time of clock pulses at the computer board clock pin. A system designer then has control of the arrival time of a pulse at a computer chip clock pin by adjustment of the arrival time of the clock pulse at the computer board clock pin, and no variation is introduced between vendors who adopt the invention in their design of computer boards.
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