A common PCIe application, such as a server card, consists of several building blocks, which all need a reference clock. In the mostly used Common RefClk architecture, the clock is distributed from a single source to both RX and TX. This requires either a clock generator with high output count or a buffer like the LMK00301. The buffer simplifies the clocking tree and provides a cost and space optimized solution. While using a buffer to distribute the clock, consider the additive jitter. The LMK00301 is an ultra-low additive jitter PCIe clock buffer suitable for all current and future PCIe generations.