Riddle: What numbers 3.8 billion in 2007 and is expected to grow to 4.5 billion by 2011? The population of China? Nope, that’s only up to 1.3 billion – we’re looking for triple that. World population is about 6.6 billion, so that’s not it.
Hint: It’s an electronic component. Ooooh, why didn’t we say so in the first place? OK, well, we might be close to that many transistors on a chip? Nope, these components are much bigger than transistors, and 3.8 B to 4.5 B in four years wouldn’t be tracking Moore’s Law would it?
If you answered “LCD Displays,” well, probably you read the title of the article. Oops — I wonder how many times THAT’s given us away? The thing is, there are LCD displays going into almost every electronic product today and into lots of electronic products we don’t even have yet. Those displays change almost daily – different sizes, different resolutions, different standards… If you’re designing a typical consumer product, your display options probably change three or four times during the design cycle.
With all that change, one of the major requirements for a device to drive your display should perhaps be programmability. That way, you can take the latest, best-est, most cost-effective-est one at the last minute and be the hero of your design team. The traditional problem with this strategy is that the programmable devices that could drive displays have been too expensive and too power-hungry for portable applications.
Now, however, there are programmable logic devices with both the wherewithal and the frugality needed to drive portable device displays – and with considerable room left over for integrating other logic functions that might be lying around on your board. This week, Actel and Attodyne rolled out a new set of video demo boards using Actel’s ultra-low-power Igloo programmable logic devices as display controllers. These kits have two parts: a main board with the Igloo device and a number of I/O connectors, and an LCD adapter board with the actual LCD display, an EEPROM, and the backlight controller. The LCD Adapter board attaches to the main board through a 50-pin connector, so you can choose from (and swap between) a 2.7”, a 4.3”, and a 7” LCD with resolutions ranging from WVGA to QVGA.
These kits include software, a demo design, a power supply, and DVI-D cables. There is also a wide range of IP available in the form of reference blocks that can get you far down the road on implementation without having to code up too much of your own HDL. Available blocks include memory controllers, color conversion, on-screen display management, an alpha blender, a frame grabber, color management, an image scaler, a 1-channel LVDS TXSDR, and a video timing generator. That should be just about everything you need to get you started on the display for your GPS device, media player, industrial handheld, medical portable, or whatever kind of handheld portable device you’re designing.
The Igloo device is very low power and has what the company calls a “Flash*Freeze” mode that enables easy entry into and exit from a static low-power mode. Since a large portion of a typical handheld’s power budget goes to the display (often 50% or more), the power management functions of the Igloo device can be cleverly applied to save a good deal of energy in the display and backlight functions.
Also, because the Igloo devices are rich in logic resources, you should have enough leftover logic and I/O pins to integrate other functionality from your design. Typically, once a designer drops a programmable logic device onto his board, he gradually migrates more and more functionality into that device, reducing his BOM, saving power, and simplifying the overall design.
Of course, in portable design, power and flexibility aren’t the only considerations. Board space can be extremely limited, and BOM cost is also a big consideration – particularly in medium- to high-volume consumer devices. Actel has just announced some versions of Igloo in packages as small as 4mmX4mm; you won’t do much better than that on board real estate. They also have devices in the sub-$2 range in volume, so the total cost is very low – in power, board real estate, and silicon — for a device that can drive your display, integrate other functions from your design, and retain flexibility to make design changes at (and even after) the last minute.
This announcement is probably the first of a string of announcements we’ll see that are pushing more sophisticated programmable logic devices into the portable space. Historically, portables have had little use for programmable devices because of their high cost, comparatively high power consumption, and because they weren’t particularly space-efficient – particularly if you considered the configuration logic they brought to the party as part of the cost of doing business.
New generations of devices emerging now, however, have solved those problems by a variety of means, and we should see cheap, fast, small, low-power programmables going after portable, battery-powered, and handheld sockets in a big way. The advantages to us as embedded system designers are shorter design cycles, more flexibility late in the game, and fewer devices on our final board. Also, programmable controllers allow you to inventory a single base board (like Attodyne did with the demonstration kit, actually) and drive multiple product variants with different display types from the same physical hardware.
In addition to display driving, these programmable logic devices can do a wide range of tasks in portable systems like power management, controlling mass storage devices, bridging incompatible interface standards, and extending the life of outdated ASICs and ASSPs by adding key functionality and capability. If you’re creating one of the 4.5 billion LCD display devices we’re supposed to see in 2011, you’ll probably think of even a few more.
