May 23, 2007 -- The new EXP expansion module specification defines a versatile, high performance, cost-effective way for FPGA designers to add functionality to their prototype platforms. By using EXP-enabled boards, designers can customize their hardware development environment and take full advantage of their FPGA designs. This article explores the features and advantages of the new EXP specification.

With the exploding use of FPGAs as main system components, combined with the plethora of FPGA development boards, the argument for using off-the-shelf components seems to make sense. The downside to this approach is that it can be difficult to find a FPGA development board that has the exact features that you might be looking for. All too often there are boards that seem to contain just about every function and interface that you can think of – except the one that you really need. And then there's the other side of the coin with regards to all of the included functions and interfaces, which is why pay for all of these extra bells and whistles if you aren't actually going to use them?

What many designers are looking for in a FPGA platform are the basic circuits to support the FPGA and something that gives them easy access to the FPGA I/Os. This way, specific functions and interfaces can be added to a standard baseboard through daughter cards or connected via cables to other existing hardware. Such a development platform offers the greatest flexibility, reduces cost, and provides the exact needs for a particular prototype setup.

The new EXP specification defines a versatile expansion interface to FPGA baseboards, allowing designers to add application-specific daughter cards and easily connect to the FPGA I/Os. With an EXP-enabled board, you can add functions from a growing list of off-the-shelf EXP modules or you can focus your efforts on building your own add-on module(s) while leveraging the existing baseboard functions. The EXP specification was developed exclusively for the unique requirements of FPGA development boards. Let's explore these requirements to better understand the advantages of the EXP specification.

By Jim Beneke. (Beneke is Director of Global Technical Marketing for the Electronics Marketing Group at Avnet.)