The FPGA’s inherent flexibility has proven indispensable for the creation of external I/O interfaces. However, unless I/O is implemented on a daughter card (mezzanine module), replacing the physical I/O components and connectors requires changing the FPGA board design. To avoid these costs, designers have historically relied on the PCI Mezzanine Card (PMC) and Switched Mezzanine Card (XMC) standards. The problem is that these were developed years ago for general purpose solutions such as single-board computers— not FPGAs.

The FPGA Mezzanine Card (FMC) standard, developed by a consortium of companies ranging from FPGA vendors to end users, specifically targets FPGAs, increasing I/O flexibility and lowering costs in a broad range of applications.

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