2.1 GHz 1:4 fanout buffer — what it handles
The Renesas 8S89831AKILF is a 1:4 fanout buffer designed for distributing high-speed differential clock or data signals. It accepts CML, LVDS, LVPECL, or SSTL inputs and delivers ECL or LVPECL outputs, all differential throughout. The part runs from a 2.375 V to 3.465 V supply and handles signals up to 2.1 GHz, making it a fit for telecom line cards, data-center switch fabrics, and test equipment where a clean fanout tree is needed without adding PLL jitter.
Input and output flexibility
The buffer accepts four common differential standards on the input side — CML, LVDS, LVPECL, and SSTL — and outputs ECL or LVPECL. That range means it can sit between a SerDes or FPGA output and multiple downstream receivers without needing external level translation. The 1:4 fanout ratio covers a typical clock-tree branch: one clean source drives four loads, all at the same output swing.
The operating range spans -40°C to 85°C, covering industrial environments — outdoor base stations, motor-drive backplanes, and uncontrolled telecom cabinets. The exposed pad also improves ground-plane return for the high-frequency signals.