| 摘要 |
A field-programmable gate array ("FPGA") may include data receiver and/or transmitter circuitry that is adapted to receive and/or transmit data at any frequency(ies) or data rate(s) in a wide range of possible frequencies or data rates. Phase-locked loop (PLL) circuitry may be needed for operation of such receiver and/or transmitter circuitry. For satisfactory operation over the wide frequency range, multiple PLL circuits are provided. One of these PLL circuits may be capable of operating over the entire frequency range, possibly with better jitter performance in some portions of the range than in other portions of the range. One or more other PLL circuits may be provided that are focused on particular parts of the broad range, especially where the jitter performance of the first-mentioned PLL may not be adequate to meet some possible needs.
|
