Original Post by Bob Waddell, Dec. 7, 2008

In recent years, the 7.0″ wide VGA (800 x 480) digital TFT has become one of the most popular displays in the world. The consumer applications are numerous – portable DVD, rear seat entertainment and especially digital photo frames use this display in the tens of millions annually. There is a great deal of interest in this product for commercial and industrial users too, and for good reason:

• A 7.0″ wide TFT has an active area of approximately 6″ x 3.6″, which is easily visible
• The wide format display makes it a perfect choice for applications where two windows are desired – say, one window for a graphic image, the other for related data
• It is large enough to have a touch screen that can be easily used

However, the immense volume of the 7.0″ WVGA in the  marketplace has created an issue in the industrial space. The TFT manufacturers who focus on the industrial market are committed to supplying displays that provide the following key features:

• Long term support — minimum 3 to 5 years
• Wide operating temps — -20 to +70C is standard
• Backward compatible design changes — if a product is modified, it is relatively transparent to the user: Mounting hole locations and connectors don’t change; interfaces and pinouts don’t change; and the supply is not interrupted.

The high volume of 7.0″ consumer displays has driven prices down so low that many of the industrial suppliers initially did not offer a product. Consumer suppliers, when seeing a periodic slowdown in demand, would flood the market with their products at prices far below what the industrial TFTs can build them for. It is not unusual to see a consumer-grade 7.0″ WVGA TFT available at a fraction of the cost of an industrial display.

There are now several industrial TFT suppliers that offer a 7.0″ WVGA TFT in a variety of configurations:

• LED or CCFL backlight
• Up to a -30 to +80C operating temp
• With or without touch
• TTL or LVDS interface

None of these are available at pricing comparable to the consumer products that come into, then exit, the industrial space. But that is not the market that they are competing against either.

Every OEM company needs to do what is in their best interest when it comes to deciding what display is the best choice for their product. It is extremely important to keep in mind that long-term availability, a consistent product offering and uninterrupted supply can save a tremendous amount of time and engineering resources just a few years down the road.