Bridging Advances Bring Better Design Options
Posted 05/24/2016 by Grant Jennings
Change is constant for embedded video system designers. Over the last few years designers have seen systems that incorporate mobile application processors with an entirely new level of capability, the adoption of new standard interfaces originally developed for the mobile consumer market, and the introduction of a new generation of lower cost image sensors and displays. These advances have had a profound impact, not only on the design of smartphones and tablets, but on applications including virtual reality (VR) systems, drones, DSLR cameras, and industrial displays.
For video system designers, coping with these evolving technologies is no small feat. One minute you’re designing for one display interface standard; the next you’re trying to support another emerging standard or figuring out how to split inputs from a single interface across multiple displays. Take a VR headset design for example. Modern headsets are moving to two displays, one for each eye. How do you convert incoming video from a single MIPI DSI interface into two MIPI DSI interfaces at half the bandwidth if your applications processor only has a single DSI interface to drive the display? In the industrial market designers building HMI solutions face similar challenges. How can they leverage the latest capabilities of mobile applications processors yet preserve their significant investment in legacy displays with OpenLDI, LVDS or proprietary interfaces? And how do designers who want to create depth perception or an augmented reality system merge multiple MIPI CSI-2 camera inputs into a single larger frame simultaneously?
With performance requirements in many of these markets rapidly climbing, it’s tough to predict exactly what type and/or number of interfaces your system is going to need. Clearly the ability to quickly bridge between different interface types or support conversion to a particular interface standard has become crucial for an efficient and successful video system design.
Unfortunately, current bridging options are pretty limited. The few discrete solutions available typically offer minimal performance and virtually no design flexibility. And building your own custom solution from the ground up in an ASSP takes far too long and is far too costly.
Instead of relying on discrete devices with their limited performance or semi-custom circuits with their long development cycles, what if you could build bridges with a programmable device that combines the design flexibility and short development cycle of a low power, small form factor FPGA with the optimized functionality of an ASSP? By designing flexible physical interfaces on the edge of the chip surrounded by a mobile FPGA fabric, such a device could be highly customizable. And by supporting a wide range of new interfaces and protocols as well as a long list of legacy interfaces, it could offer comprehensive conversion capabilities while consuming minimal power.
Lattice has done just that. The CrossLink FPGA solution is the world's most versatile video interface bridge to support virtually all the leading protocols for mobile image sensors and displays. Featuring a MIPI D-PHY bridging solution delivering up to 12 Gbps for displaying high resolution, high bandwidth content at 4K UHD, CrossLink offers excellent performance in a tiny package while consuming < 100 mW.
As new technologies continue to enter the market, embedded video systems will grow in both capability and complexity. Look for bridging solutions to play a vital role in helping designers reach higher levels of design flexibility and innovation.