The evolution of FMC to FMC+ has some similarities to PC buses. Years ago, as peripheral component interconnects (PCI) on commercial PCs evolved from PCI to PCIe, the preference for data bus moved from a parallel bus architecture to a serial lanes approach.
However, as FMC moved to FMC+, this standard added more lanes while retaining full electrical and mechanical backwards compatibility. More high speed serial lanes on FMC+ enable designers to utilize the highest performance devices from suppliers such as Texas Instruments and Analog Devices.
An example of a product that has already realized this potential is the FMC134 from Abaco using state-of-the-art devices from Texas Instruments. More data bandwidth means more analog bandwidth or more channels; however, all this performance missed the mark for some applications such as electronic warfare (EW). In the world of EW, latency is often a critical requirement. Both FMC and FMC+ have 160 single-ended connections for a low latency parallel bus - so FMC+ brings little to these applications.
An interesting view of FMC and FMC+ is the fact that often, for a specific FMC board, designers are unable to utilize all the pins for both the parallel and all 24 serials lanes - thus leaving unutilized pins. Some COTS providers took this as an opportunity to innovate by enabling FMC stacking: however, that hasn’t seen wide adoption due to space constraints. One COTS product from Abaco is the CRS821 which uses this approach for small form factor development systems.
At Abaco, we believe the initial reasoning behind the inception of FMC and the upgrade to FMC+ remain very relevant. As a COTS provider of state-of-the-art FPGA technology, the standard FMC/FMC+ form factor allows for rapid prototyping and a path to a rugged deployed system.
There is increased pressure from tax payers to get more out of each tax dollar. FMC as an enabling technology of next generation rapid prototyping and deployment is likely to see continued growth. FPGA technologies will continue to see adoption in the software defined radio, electronic warfare, and advanced sensor/radar applications. Each of these spaces share some common needs, such as more bandwidth, more channels, and a more complete solution. FMC+ should do quite well in these spaces as systems providers will need to compete on price and speed.
Another advantage afforded by the modularity of FMCs is the ability to simplify technology insertion. By using FMCs in a design, customers can upgrade components in a system, rather than overhauling the entire device. Similarly, this modularity enables customers to standardize on a common hardware platform across multiple programs – maximizing design reuse, accelerating time to deployment, and reducing the lifetime cost.
FMC is alive and well, with many COTS providers participating - and this should result in a healthy eco-system of technology.