This application note describes how to interface 3.3V differential Low-Voltage Positive Emitter Coupled Logic (LVPECL) drivers with Xilinx® 2.5V differential receivers, including Virtex®-II Pro, Virtex-II Pro X, Virtex-4, Virtex-5, Spartan®-3E, and Spartan-3 FPGA 2.5V LVPECL and Low Voltage Differential Signaling (LVDS). Several interface modifications are presented with supporting IBIS simulation results.


xapp696.pdf