While CPUs rely on busses such as PCI or PCI Express, FPGAs are built to interface directly with IO devices. With this comes a set of particular IO requirements and an ANSI/VITA 57 FMC specification driven by the VITA working group.
Understand the FMC Standard and Get the Result You Want
FMCs provide a great deal of freedom for designers to deliver high bandwidth, low latency solutions with minimal hardware since the standard bus structures are bypassed and the interface devices' removal. The FMC standard has considerable advantages in terms of I/O throughput and flexibility but matching an FMC card with a carrier has to be done carefully.
FMCs are fertile ground for custom developments. There is no reason why FMCs can't be used to implement a mix of technology on one card, absorbing system-specific I/O with minimum design.
During power-up, the host interrogates the mezzanine to determine its primary power supply requirement and then provides it if it can. Since the FMC relies on the host, instead of regulating its primary power supply, more PWB real-estate opens up for I/O or other functions.
FMC modules are available in air-cooled and rugged conduction-cooled formats with single and double-wide configurations. Single wide FMCs are by far the most common.
The key to FMCs is I/O flexibility on a small open standard mezzanine card. Non-FMC-based FPGA I/O solutions still provide slightly higher levels of I/O density, but only for the highest levels of performance requirements. Typical FMCs allow for around four to eight ADC/DACs <1Gsps per channel, two or four ADC/DACs in the multi-Gsps per channel range. Other FMC functions on the market include fiber-optics, DSP, Ethernet, and digital I/O.
Explore our range of high-performance FMC solutions, allowing system integrators to meet the demanding networking and I/O requirements of RADAR, EW, SIGINT, COMINT, ECM, ESM and C5ISR applications.
What is FMC+
A new generation of FMC modules known as FMC+ is emerging through the VITA 57.4. FMC+ modules use a host connector with additional rows to increase the number of high-speed serial connections from 10 full-duplex to 24 full-duplex channels. Some FMC+ modules increase the channel count to 32 full-duplex by using an additional connector. An FMC+ host can also accommodate FMC modules for backward compatibility.
FMC to FMC+
The FMC standard defines a small format mezzanine, similar in width and height to XMCs or PMCs, but around half the length. This means FMCs have less component real-estate than many other open standard formats. However, FMCs don’t need bus conversion, such as PCI-X, and have simplified power supply requirements which means that FMCs could actually have more I/O capacity than their XMC counterparts. Let’s break this down.