The SY56028XR is a fully differential, low voltage 1.2V/1.8V/2.5V CML 4:1 MUX, with input equalization, and integrated 1:2 Fanout Buffer. The SY56028XR can process clock signals as fast as 4.5GHz or data patterns up to 6.4Gbps.The differential input includes Micrel's unique 3-pin input termination architecture that interfaces to DC-coupled 2.5V/3.3V LVPECL, 1.2V/1.8V/2.5V CML or LVDS differential signals. For AC-coupled input applications, an internal voltage reference is provided for input bias. Input voltages as small as 200mV (400mVpp) are applied before the 9, 18, or 27-inch FR4 transmission line.The SY56028XR operates from a 2.5V ±5% core supply and a 1.2V, 1.8V, or 2.5V ±5% output supply and is guaranteed over the full industrial temperature range (-40°C to +85°C). The SY56028XR is part of Micrel's high-speed, Precision Edge® product line.