Electromagnetic emanation exploration in FPGA-based digital design

As semiconductor technologies have been shrinking,the speed of circuits,integration density,and the number of I/O interfaces have been significantly increasing.As a consequence,electromagnetic emanation(EME)becomes a critical issue in digital system designs.Electronic devices must meet electromagnetic compatibility(EMC)requirements to ensure that they operate properly,and safely without interference.I/O buffers consume high currents when they operate.The bonding wires,and lead frames are long enough to play as efficient antennas to radiate electromagnetic interference(EMI).Therefore,I/O switching activities significantly contribute to the EMI.In this paper,we evaluate and analyze the impact of I/O switching activities on the EME.We will change the circuit configurations such as the supply voltage for I/O banks,their switching frequency,driving current,and slew rate.Additionally,a trade-off between the switching frequencies and the number of simultaneous switching outputs(SSOs)is also considered in terms of EME.Moreover,we evaluate the electromagnetic emissions that are associated with the different I/O switching patterns.The results show that the electromagnetic emissions associated I/O switching activities depend strongly on their operating parameters and configurations.All the circuit implementations and measurements are carried out on a Xilinx Spartan-3 FPGA.