subject: Mobile Phone Lcd Module Backlight Energy Saving Drive And Control To Be Two-pronged Approach [print this page] Energy has become a hot topic nowadays, and selling points. Phone was undoubtedly the most power-hungry part of the LCD module, LCD module energy saving nature is a pioneer in mobile phone, while the energy needs of LCD module backlight LCD Driver and control both.
With the camera, mobile TV, GPS and other functional modules increases, more and more cell phone battery life is short, increase in the mobile phone battery capacity under limited circumstances, the significance of energy conservation is very important, energy conservation has become a hot topic nowadays and selling points. Phone was undoubtedly the most power-hungry part of the LCD module, LCD module energy saving nature is a pioneer in mobile phones, and LCD module energy you need to drive and backlight control both.
LCD drive is the key of standby time
LCD driver and LED backlight LCD module's power is large, however, the drive power consumption as compared with LED backlight, the former much smaller than the latter, it seems that LCD driver insignificant impact on standby time. Really? Sitronix LCD Co., Ltd. Deputy General Manager of money-driven business groups were gold-dimensional interpretation of this: "LCD backlight modules account for 90% of power consumption, and it seems as if the power consumption of LCD Driver is nothing, but do not forget Backlight not always open, and in most of the time, the backlight is turned off, so the real impact of LCD Driver is a key factor in standby time. "
Drive past there is a big waste of power, such as LCD 14V voltage required to drive, but drive a common practice is to receive the voltage of 3V, do step-up seven times, in fact, need only 14V, have to fold down to 21V! Qian Jin-dimensional, said: "Our power-saving concept is 'good enough', so we did a lot of Driver IC comparator which, by the comparator IC is now needed to determine the voltage times the voltage level of this control . from the past to just a good 21V 14V, representative of the gap which we can save power consumption by 30%. "
Winter outdoor use mobile phones, we may all feel the slow response of the phone screen, mainly because of low temperature viscosity of the liquid crystal itself will increase, this time to reach room temperature liquid crystal display similar to need a higher voltage drive, so traditional drive power consumption at low temperature, the greater the more. Sitronix in its development of environmentally friendly Green Driver drive built into a temperature sensor, so that IC can always know the current temperature in order for all different temperatures to adjust the performance of analog circuits. Qian Jin Victoria said: "The low temperature environment, the frame rate as fast as the need and room temperature? This is a question worth considering. In fact, we can reduce the frame rate at low temperatures, making the low power consumption but less." Energy conservation is a major feature of Green Driver to Green Driver in CSTN the application, for example, Sitronix shipments during the first half of this year to more than 8,000 million units.
Backlight power-saving technology is irresistible
Used in mobile phones and other handheld devices with small screens is LED backlighting made this point with the large-size screen and more different still using CCFL backlight, LED CCFL relatively more environmentally friendly energy. Generally QVGA? Level needs four LED backlight display phone, LED backlight power consumption accounted for the entire module Jiucheng. Currently in use LED's forward voltage drop VF nominal voltage of 3.4V 0.2V, LED backlight of a new generation of VF are falling, which means its own power consumption is declining. But PowTech Resources (Shanghai) Co., Ltd. Senior Engineer Yen Kuang that, while using low forward voltage drop VF of the LED backlight can power about 15 to 18%, but the price may be slightly more expensive.
In addition to its own power LED down outside, LABC, and CABC are two other ways to power the backlight. LABC / CABC the ABC refers to the adaptive brightness control, L refers to the ambient light sensor. Sunlight during the day, due to external light, strong, mobile phones may want to use 100% of the backlight to make the picture to see clearly; but to the shadows, reducing the external light, mobile phones can reduce the backlight to 80% in the evening, the environment light interference reduction, backlight can even be further reduced to 70%. Detected by external ambient light sensor automatically adjusts LED backlight intensity to achieve energy saving, which is the basic concept of LABC.
CABC the C refers to is the content (Content), that is, image analysis. It adds a new LCD driver features an image content analysis, when the pictures sent in, the image analyzer will first increase the contrast of 24%, then the backlight brightness decreased by 24%, this time not get the image with the original image display processing is almost the same, the human eye were almost impossible, but to achieve a saving in backlight. CABC play all the time saving features, this treatment makes the backlight power consumption can be reduced about 24%.
Yen Chung-kwong, that because each individual use of the environment vary widely, LABC can only estimate a saving of about 7 to 18%; and for LABC / CABC, the increase in ambient light sensor or image analyzer will increase the cost and power the phone itself. Victoria said this money, gold, silicon innovation will LABC / CABC technology integrated into the drive, manufacturers need to increase individual components, and therefore did not raise prices, the fare increase is not a value-added technology, the customers do not increase costs. Another part of the increase in power consumption because it is attached to the original function, and so they are also very limited.
Qian Jin-dimensional description: "The top five mobile phone manufacturers in the world, basically has launched with LABC / CABC some of the features of the phone, such as the Nokia N95. But in this part of the domestic mobile phone is still relatively backward, but this trend is unstoppable I estimate the next couple of years will certainly be a large-scale spread. "
