MTF-TW70SN731-LB (aka UMSH-8013MD-1T)

• 7.0” Digital TFT available with and without Touch Screen
• Outline dimensions are 164.0(W) x 104.0(H) x 6 (D)mm
• 16×9 Aspect Ratio
• -30°C to + 80°C operating temp
• Resolution is 800 x RGB x 480 dots.
• LVDS interface and built-in voltage board (V-Com, T-Con, DC/DC)
• LED backlight is 500 Nits

Pros: high noise immunity and low noise generation, good for long distanced between LCD and controller, quicker data transfer over fewer data lines, generally lower power consumption

Cons: two wires required for each data transmission

Applications: automotive, industrial, military

Specification: mtf-tw70sp731-lb-_20071221_

Posted by: John Clauson

Original Post by Steve Gereb, Jan. 7, 2009 

Over the holiday break we received notification from NEC Electronics that two 3.5″ mobile displays are being phased out due to discontinuation of the LED backlight. The products are the NL2432HC22-22A and -22B.  LTB orders will be due in mid-March 2009.

For more information, please see the phase out notification:

2h-fy08-phaseout-jan09mobile-lcd2

Original Post by John Clauson, Jan. 8, 2009

The trend for LED backlights in TFT displays are increasing at a rapid pace. More and more suppliers are offering new LCD sizes and formats on a regular basis.

NEC is introducing 5 new TFT’s incorporating a newly designed LED units that achieve both long operating life of 70,000 hours and low power consumption in the backlight system.

2. Compatibility
Each of the new modules is compatible with NEC LCD Technologies’ conventional standard products of the same size in relation to outer dimensions, position of mounting holes, and screen center. Each also maintains signal compatibility with conventional products. Thus, the modules can be replaced easily without the need to change any of their peripheral appliances.

3. Wide operating temperature range
A wide operating temperature range, from –20 to +70 degrees Celsius, guarantees operation even in extreme conditions. Moreover, the luminance of the white LED backlight performs exceptionally well under low temperatures, even from initial startup.

Material referenced above can be found on NEC’s web site:

http://www.necelam.com/news/newsdetail.html?page=long_life_low-power_white_led_for_industrial_display#1

The main characteristics of the new modules are as follows:

1. Long-Life and Low-Power White LED Unit
The newly designed white LED unit, outperforms conventional cold-cathode fluorescent lamps (CCFL) with an operating life of 70,000 hours at room temperature (25 degrees Celsius). It reaches an operating life of 60,000 hours at a high temperature of 60 degrees Celsius, and boasts high reliability that is ideal for display devices in industrial equipment exposed to severe environmental conditions. All new modules reduce power consumption by more than 20 percent compared to conventional CCFL backlight systems.

For more information on this TFT module, check out these documents:

lq150×1lg82_pa

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.

Original Post by Vignesh Sanmugam, Dec. 5, 2008

The trend of the twenty-first century is that everything is going flat: the world, the economy, the stock market and, now, even displays —flat panel displays (FPDs) are everywhere.  LCD TVs and LCD Monitors have dominated the consumer market with their aggressive pricing and extensive marketing.  And let’s not forget about consumer favorites such as iPods and other MP3 players, mobile phones, PDAs and kids toys. As the prices for TFTs plummet, displays will continue finding their way into almost every possible application (including the toys for your children’s Happy Meals). The technological advancements within the Flat Panel Displays are making designers’ dreams a reality. The choice of designing with a display has thus become inevitable, but the dilemma is “Which display do I use?”It is always that first step which is a challenge, but with displays it is one the easiest decisions. From the CEO to Marketing, everyone wants a Flat Panel Display in their product, which is no longer a luxury but a necessity to be competitive. It is assumed for this discussion that the overwhelming consensus is to move forward with a TFT Display over Color Passive LCD or Organic Light Emitting displays. As one steers through the requirements for a TFT Display, a broader outline consists of mechanical specifications, electrical specifications, optical specifications, environmental specifications and functional specifications.

Deciding the diagonal of the display establishes the foundation for the design process. This is based on the application and the overall mechanical considerations of the final product. Flat Panel Displays are generally categorized as Mobile/PDA Displays (1.0” to 3.5”), Small Displays (3.8” – 7.0”), Medium Size Displays (8.4” to 12.1”), Monitor Displays (15.0” to 19.0”), Large Displays (20.1” to 32”) and Signage Displays (32”+).  The displays that are developed for the industrial market place are considered to have a minimum 3 to 5 years life cycle and the specifics are subject to each display manufacturer’s focus and road map. The LCDs that are developed for the mobile and laptop market tend to be volatile from a lifecycle perspective and this is where your distributor’s knowledge base is of great value in making your selection process.

The size of the display and the resolution of the screen are somewhat interrelated. As for the resolutions, there are limitations to what is available with the size of the screen. The size of the screen and the Aspect Ratio (the ratio of width to height) signifies the maximum available pixel options for the selected display. Wide format displays with mostly a 16:9 aspect ratio were initially used in AV applications and are now commonly sought after for many industrial applications too. TFT displays are either based on a-Si (amorphous silicon) or p-Si (polysilicon), with the p-Si having the ability to accommodate a higher pixel density within a given display size. In addition the p-Si technology has many additional advantages such as the driver IC integrated into the substrate, high-aperture ratio and increased electron mobility. There are now many displays with nonstandard resolutions that could be of interest depending upon the application. The viewing angle of the display is another design consideration that is based on the application and the angle of user interface. One of the challenges with the viewing cone of the display is the issue of color shifts that could significantly impact the selection of a particular display or manufacturer. Most TFT manufacturers now have displays that have wide and symmetrical viewing cones. 

The brightness and contrast of the displays are the next vital part of the selection process. The display brightness is measured in “nits”, which is a unit of illuminative brightness equal to one candela per square meter that is measured perpendicular to the rays of the source. Contrast Ratio is a measure of the brightness of white to the darkness of black that the display is capable of producing. If this ratio is high, the image tends to be sharper and vibrant. The application and the environment under which the display is to be utilized / viewed determines the target levels of the brightness and contrast required for the LCD that is being selected for the given purpose. Note that determining the optimal combination of brightness and contrast can pose a challenge as these are perceived values based on each individual. A general rule of thumb with respect to brightness and contrast is that decreased brightness can be compensated by increasing luminance contrast.

One of the design considerations in determining the brightness of the display is the backlight system of the display. Until recent time, most displays incorporated CCFL (Cold Cathode Florescent Lamp) back lights. The CCFL backlight system contributed to the major part of the power consumption of a display. In addition, these CCFL backlights required a high voltage kick-off for the start and this not only increased the need for an additional component (and inverter), but also could pose interference issues for the smooth functionality of the Flat Panel Display. The increased demand for low-power solutions, instantaneous kick-off during extreme cold weather conditions, EMI/noise issues and thermal management challenges, more and more displays are now manufactured with LED backlights. Thus, the selection of the backlight system also targets any and all power requirements of the display/application. The whiteness of the white LEDs can deteriorate over a period of time, which can impact the color performance of a display, but LED backlights hold far more benefits over CCFL backlights, especially as LED costing continues to decline.

The critical component of designing displays is to ensure that the display being selected for the application can be appropriately driven by the electronics that is available to the designer. The display interfaces differ from panel to panel and manufacturer to manufacturer. In the digital world, displays with resolutions of VGA and above fall into two main categories – CMOS/TTL, which is a parallel interface or LVDS which is a serial interface.  Whereas sub-VGA panels can vary between built-in capabilities, directly accepting TFT signals or the need for specific Timing Controllers (TCON) to provide the required signals to drive the display. Driving these displays can be accomplished in many ways depending upon the application and or available resources.

The panels can be driven (i) Directly by Microcontrollers / FPGA (ii) Single Board Computers or (iii) AD Controller Board. The current day processors, controllers and/or FPGAs have the necessary built-in capabilities to drive a TFT display. This largely depends upon the display if it is a 6 or 8 bit/color LCD. Another option is for the display to be driven by an SBC which has built-in TTL or LVDS capability. It is critical that the timings are appropriate to ensure effective functions of the Display. In an event the Single Board Computer selected does not have a TTL output for the Display but only LVDS and the display is a TTL one , you can use a low-cost conversion board. The off the shelf option is to use a standard Display Controller Board that is capable of accepting the required input such as analog RGB or S Video or Composite Video or DVI and drive the appropriate CMOS/TTL or LVDS display.

Thus, the critical design considerations for a TFT Display are: its size, resolution, brightness, contrast ratio, viewing angle, back light system, power and interface.

For any questions, please comment or email us at ask.lcd@avnet.com.

Original Post by John Clauson, Dec. 3, 2008

Endicott Research Group (ERG), specialist in power solutions for LCD backlights since 1979, has releasedtwo new high-efficiency, low-profile Smart Force™ LED driver boards as standard products for a wide range of industrial and medical LCDs.The SFDE (Economical) and SFDM (Mini) Series provide full function power supplies with optimum power for high brightness as well as lower power consumption and lower cost in an exceptionally compact size. Both driver boards are less than 5 mm in height, and both provide brightness stability over a wide input voltage and can power up to 6 LED strings. 

“We designed these driver boards to provide a more compact and more economical solution for customers who are backlighting LCDs up to 15 inches diagonal and who don’t need all of the full-function performance features of our existing SFDL and SFDC Series driver boards, such as wide-range onboard PWM dimming ratio,” said ERG Sales & Marketing Director Bill Abbott. “The SFDE and SFDM Series provide a lot of bang for the buck, with built-in compatibility for a wide range of OEM LED-backlit displays.”

The SFDE Series provides a plug-and-play solution with an outstanding cost/performance ratio. It measures only 1.11” (28.2 mm) x 3.10” (78.7 mm), and is less than 5 mm high. It provides an input voltage range of 10-20 V, with external PWM dimming to 500:1.

The SFDM is the most compact LED driver board ERG has developed to date, measuring only 0.96” (24.4 mm) x 2.19” (55.6 mm, with a height less than 5 mm. It provides an input voltage range of 8-20 V, with external PWM dimming to 250:1.

Both driver boards can be used with ERG’s new and improved Smart Force™ LED rails as a drop-in replacement for CCFL rails for a number of OEM LCDs. Smart Force™ LED rails feature a proprietary ERG design that provides exceptionally good thermal management to keep the LEDs from overheating. ERG’s new Smart Force™ SFDE and SFDM LED driver boards are available as standalone products from stock, or as kits that include the driver boards and LED rails, also available from stock.

For more information, please email Ask.LCD@avnet.com.