SNAA386 November 2023 CDCE6214 , CDCE6214-Q1 , CDCE6214Q1TM , LMK00301 , LMK00304 , LMK00306 , LMK00308 , LMK00334 , LMK00334-Q1 , LMK00338 , LMK03318 , LMK03328 , LMK3H0102 , LMK6C , LMK6H , LMKDB1104 , LMKDB1108 , LMKDB1120 , LMKDB1202 , LMKDB1204
In PCIe systems, the REFCLK is a differential High-Speed Current Steering Logic (HCSL) clock. HCSL drivers source current into an external 50-Ω load. Low-Power HCSL (LP-HCSL) reduces the power consumption of the driver, and integrates the termination resistors into the driver, removing the need for external components. LP-HCSL drivers are more capable of driving long traces compared to HCSL, and are able to be AC-coupled without change to the termination or swing. Figure 4-1 and Figure 4-2 demonstrate the drivers for HCSL and LP-HCSL, respectively.