LCD ram/Semi-anti-wear technology analysis "turn"

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My topic should be a bit longer. But the general section is as follows:
1.LCD ram;--> This item is now over
2.OCA Attachment Method;==> This temporarily cannot give the update time, but will be as soon as possible.
3. Jieduan a machine so-called semi-anti-wear screen;-->12/23 11:51 has been updated.
4. The use of Meizu for such a long period of experience and advice;

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Thank you for your added support. The next content is already in preparation and writing. Because the online writing, so speed not to go, a little Ann. Please forgive me.
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Under Notice:

posted by ultrahigh pressure on 2011-12-23 12:50
Tall man, can analyze the Apple 4 screen why so thorough, feel keep abreast on the screen, and in the sun, the display effect is also very good. Personally feel much stronger than M9 display. MX has not yet seen, not clear.

Gao deserve, en, the next OCA topic is to talk about this oh. Basically, there are two reasons: the Apple itself is caused by the UI, but with the OCA attached to the way also has a certain relationship. Since the comparison should be the same UI, the same background in the case of comparisons, then, only the OCA affixed to the same way. However, the OCA approach will reduce the yield by 10% and the subsequent maintenance costs double increase. As for the good reaction in the sun, it is because the brightness of the apple itself is about 100 higher than the Meizu, plus the OCA way to remove the air between TP and LCD, to avoid the mirror effect caused by air. Roughly so.
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First of all, the first topic. LCD RAM
Origin
Recent Meizu Forum and Millet Forum One of the hottest topics is LCD RAM, of course, Xiaomi recently own backyard, resulting in after-sales/complaints is the most fire.
What is LCD RAM?
LCD is literally the LCD screen (Liquid crystal display), and RAM: Random access memory (random-access memory), the two are completely irrelevant things.
is a standard LCD exploded image (without TP), pleasenotice where the red mark is in the picture.: Controls the brain of the ic--LCD.the so-called LCD ram naturally refers to whether the brain contains RAM.
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off-topic < Not interested can skip this section >
This small thing takes up the whole module < does not contain tp> 's approximately 8%~15%, namely at present monolithic 4.5 's 720P IPs price roughly is about 200, this IC price is approximately 16~30 between. < This is just my estimate, still remains to be verified >. The proportion of the total cost of mobile phone is actually very low only about 1%. Of course, the same specifications of the IC built-in RAM, it is true that the price will be different, but not too much difference. At present, the product homogeneity under the serious conditions of product competitiveness more performance for the enterprise's purchasing power and cost control capacity. Apple is a good example, the best things, the lowest price, of course, it must be the largest amount, and even a lot of enterprises at a loss to take Apple's case, for two reasons: Apple can help companies to improve the process capability, on the other hand, the need to enhance their image with Apple. < Sorry to pull a bit farther >.

Back to the chase.
does the LCD require RAM?
Since here, I have to clarify that the dog's blood plot is not a new topic, in fact, N long ago, non-high-speed products &LT;QVGA resolution of MTK Products ERA > There has been this phenomenon. This is like the N-version of the Statue of God, the plot is unchanged, Each version of the star is changing. Think of a young RGB and the beautiful people like flowers: The CPU, of course, to put on some dog blood passion. And now Lianpo old, still can eat natural only mipi. Of course mipi a person to play two horns, 2P is a must. Because this starring Mipi is the head of the head, there are more than n concubines, of which two of them are called DSi and DCs.
Below I will formally introduce the above several to join the protagonist of the passion performance. We warmly welcome you.
Mobile phone devices are many, but the main body is nothing more than screen, motherboard, battery, shell, the most core of the natural is the motherboard and screen, screen and motherboard processor will inevitably have an interface to exchange data, we call it interface (data interface).
Time back in 07 before the iphone generation, the mainstream phone size is still 2.2, the resolution is roughly QVGA, ordinary non-smartphone platform such as mtk/Infineon/Qualcomm and so on are only CPU interface (also written MPU/MCU), to adopt the RGB interface of the large screen, To add a CPU interface to the LCD RGB interface of the conversion chip. Besides, there are spi,vsync,mddi,mipi and so on;

my point is, MCU (CPU), RGB interface. Because this is the key to the existence or not of the relationship ram.
CPU and RGB are two different interfaces, in simple terms:
CPU Mode, the LCD controller is directly embedded in the LCD screen, this is the so-called Smart Display panel, the driver only through the MPU data bus to send data to the LCD RAM, as shown in the LCD directly to the built-in controller bar.
RGB mode,Must use external controller, usually refers to (mobile phone or other external processor) CPU, this time the LCD is called Dumb display panel (dummy screen), the data must pass the point, line, The frame clock and so on by the CPU controller to control the drive data display to the LCD.
Let me briefly describe the difference between the two below.
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the speed of the contest:
This is two different ways of data transmission, in general, the RGB interface to transmit data faster than the CPU interface. Because for the LCD Driver IC, the data must be sent to the Driver IC's internal RAM, and then by Driver The controller built into the IC is displayed on the LCD. In contrast, RGB is sent directly to the LCD via the interface. In the final analysis, both scenarios require a RAM to hold the data to be sent, except that the CPU is gram in the driver IC. RGB requires an interface conversion IC (this feature is integrated in the general chip and built-in gram). But it is only in milliseconds that we have to calculate the speed of time here, and the perception of the human being cannot be judged at all.
advantages and disadvantages of the contest:
In general, RGB is more suitable with the previously so-called large screen, QVGA/VGA, small screen (less than 1.8 inches) generally use CPU interface. This has nothing to do with power consumption. If you must pull the power comparison, then only say that the same drive voltage and the driving size of the theoretical CPU energy consumption is greater, Because of the external RAM. While the CPU mode control is simple, no clock and synchronization signal, compared to the RGB mode is more customized. But for the development side slightly more complex, not a simple command of the way to achieve the display function.
Here's our story to the new version of the Dog blood plot: the Mipi camp. (Want to know MIPI can self-Baidu)
MIPI is like large house, Mipi is the head of the landlord Huang Shiren. There are countless concubines below, and DSI,DSC is just two of them. These two strengths, you can think, they a long beautiful fan Huang Master, a kung fu, cool dead Huang Master. In short, the result is with Huang Master.
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The following content source network.

DSI ( video mode ).
This mode of operation is similar to the traditional RGB interface, where the host needs to continuously refresh the monitor. The control signal and RGB data are transmitted via the MIPI bus in the form of a message without the use of a dedicated data signal to transmit the synchronization information. Because the host needs to refresh the monitor periodically,The monitor does not require a frame buffer. This is the key reason why MX LCD does not require RAM.
DCS ( command mode)
The MIPI bus controller uses a display command message to send a pixel data stream to the display. The monitor should have a full frame long frame buffer to store all the pixel data. Once the data is placed in the monitor's frame buffer, the timing controller pulls the data out of the frame buffer and automatically displays them on the screen. The MIPI bus controller does not need to refresh the monitor periodically.
advantages and disadvantages of two modes
Each mode of operation has advantages and disadvantages in terms of cost and power consumption. The video mode display architecture does not require a frame buffer. However, the host regularly sends DSI video messages in high-speed mode, but consumes a lot of average energy.
Ideally, when the display does not change (or changes infrequently), the CPU of the display system should switch to a low-power mode, and the link between the processor and the monitor will be activated when needed. Due to the need for periodic refresh of the host, some CPU and memory interfaces also need to remain active, which can make the system not achieve the best power budget.
On the other hand, the command mode display architecture allows the monitor to self-refresh the entire frame buffer directly. However, it is always cost to integrate full frame long-frame buffers in the display, especially for high-resolution displays that are required by most users today. This requires that the interface chip has a larger die size. Display manufacturers also have to provide a display controller with a specific capacity frame buffer for each display resolution.
For video mode and command mode display architectures, it is often necessary to program the display controller's register to set the corresponding display resolution, appearance ratio, and operating mode. MIPI does not define any standard protocols to access these internal registers, so different monitor manufacturers can customize their own dedicated set of commands.
To get rid of conflicts between different manufacturer-specific display commands, some manufacturers prefer to have the display initialize themselves so that the monitor does not need the configuration of the MIPI host controller to work properly. In this case, the display usually has a prom memory that stores the display parameters. This is very convenient, but the prom also occupies a relatively large memory space.

after reading the above paragraph, someone should understand. In fact, this is only two ways, it is the mobile phone processor data transmitted to the LCD, and displayed, the results are the same. As Meizu engineers have said, the current processor is fully capable of handling ram at once.

Here are some of the netizens raised why 9100 and IP4 built-in RAM things to clarify.
The first is 9100, I did not find 9100 of the data, but I do not believe that 9100 of the listed products in the use of command mode, such a way although the amount of data to save the port, but there is low refresh frequency, and so high resolution and brightness of the product, Will certainly cause filker flashes to appear. And with a 9100 processor, the refresh of two WVGA product video mode is completely free of pressure.
The second is that the IP4,IP4 driver IC does have built-in RAM. But it is not used on the product side. Let me prove it.
This is the test board for Ip4/ip4s.
Look at the picture, you can compare to the next online demolition pictures, confirm is not the Apple module?
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This test system uses the Solomon SSD2825 MIPI chip that is lit using video mode. The datasheet I've got is not the official version, (SSD2805 can actually drive the Apple module, but it has to command mode). Because this product is a 3lane product, and SSD2805 can only support 2lane, the maximum bandwidth can not meet the video mode, and SSD2825 support 4lane, the highest resolution can support to 1920*1200;
Look at me in SSD2825 datasheet.
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This IC supports both the Dumb display panel and the Smart Display panel. And to our MX processor, not to mention, in fact, the processing of the full support (personal conjecture), then why did not do so. Must be to reduce the development difficulty, No need to spend too much effort on the LCD interface debugging, but the shortcomings are obvious, may occasionally appear the phenomenon of screen delay.
again to discuss why IP4 built-in LCD RAM, first IP4 built-in RAM this is undoubtedly, but the built-in does not mean that he is in use,There are two reasons for this: one is the amount of customers such as Apple, the orders are all tens of millions, such a quantity, built-in and not built-in price is basically the same. Second, Apple does not do a loss of business, then the RAM is what to use, the answer is for factory-side test use, it is known that mode, the bandwidth requirements are low, in a sense, the LCD factory end of the requirements of the test machine will also be reduced. Although Apple is a lucrative enterprise, but has to say that he is very good at suppliers, helping suppliers to reduce costs, is tantamount to reduce their own costs.
OK, now the problem is solved. What are you looking forward to? * * and the next wave of slander in the media? Come on.
Finally, we really do not need to pinch to pinch, are digital enthusiasts, but the demand is not the same. Why come to such a three-way abuse. I really think * * is the enthusiast club? hehe, I can only silently in the heart shout: Brain residue. But from another point of view * * is a successful product, Because the price is really very lethal. But at the same time the egg pain is also low-priced to bring poor quality, after-sales and so a lot of problems.
after reading the above, we should have a decision on the LCD RAM, in fact, it is Meizu cost down and use the mutilated screen, is a total rip chicken eggs. This is the act of Berthelot. I do not bother to despise some enterprises, do not really do business, but take some "global" "Fastest" "Dual core" "Top Supplier" "1999" "enthusiast" words, to help some ignorant have a fever dream of pseudo-enthusiasts to achieve their so-called Fever dream. I'd prefer to see him as an open media stupefying propaganda, and I don't want to be sympathetic to those who are fooled or are willing to be fooled.
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The LCD Ram section is updated to complete. If there is any false, please advise.

To be continue ...

[this post was last edited by Westjam on 2011-12-23 13:00]

LCD ram/Semi-anti-wear technology analysis "turn"