FPGA programmable PLL impact on EMC behavior

This paper studies the impact of EMC on a programmable PLL feature of both FPGA-based IC and PIC series microcontroller (μC). We use ACTEL FPGA IC the target IC and design the testing board according to IEC standard. By using the TEM-CELL method to measure the electromagnetic radiation from the circuit board, different PLL EMC behaviors of the PIC μC with the FPGA-based design are compared. Generally, the EMC effect of FPGA is worse than that of the commercial PIC μC. Among all of the measurement results, it shows that the different PLL output frequency setups have different and crucial EMC impact.