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36

The little piece of rubber you removed IS the connector. Elastomeric connectors look like a piece of rubber and are commonly called "zebra stripes" because the conductive carbon stripes in the rubber look like zebra stripes when viewed from the end. Image from Wikipedia:


33

LCD: liquid crystal display. Works by adjusting the amount of light blocked. Usually has a backlight but might not (clocks, calculators, Nintendo Gameboy). The green-black ones can be very cheap and are a mature technology. Response time can be slow. TFT: is a type of LCD with a thin film transistor attached to each pixel. All computer LCD screens are TFT ...


26

It is very difficult to cut round shapes out of glass or produce concave corners. Straight cuts which go all the way across a reasonably-thin sheet of non-tempered glass can be made quickly and reliably by scoring a line and trying to flex the glass there. It's not necessary to score very deep, nor very thoroughly--all that's necessary is to ensure that ...


24

Often called Zebra strips (or Elastomeric connectors). They have very thin vertical conductors that connect between flat PCB pads and things like LCD pads on glass. Here is a link with a similar pink component. http://en.wikipedia.org/wiki/Elastomeric_connector


23

The problem you are seeing is related to the construction of LED backlight circuits which require lots of LEDs. Often on poorly designed or "cheapo" designs there are LEDs or series strings of LEDs that are connected in parallel. See the typical diagram below for reference: The problem comes into play here when the forward voltage drops of each string of ...


16

It takes the right signals on both the top and bottom glass to "light" a segment (actually turns it dark, tranparent is the not-see case). This allows LCDs to be arranged somewhat in a matrix. A segment only lights when both leads are driven a particular way. The other leads are driven in a way so that no other segment is lit. These kinds of 7-segment ...


16

Liquid Crystal material, the compound inside an LCD that reacts to electrical stimulation, likes to have an AC waveform to activate. So a single pixel would have two transparent electrodes with this LC material between them, driven with a squarewave at a fairly low frequency. If the two electrodes are given the same waveform, then it's inactive, and if they ...


16

Many LCD controllers (including the ST7920) can support a variety of interface types, of which you can use one at a time. Sometimes the interface type is fixed on a given LCD display module; sometimes the interface can be selected. The exact PCB markings for selecting between interfaces (when possible) does not always match the signal names you are expecting....


16

It is possible to make a circuit out of logic gates that would be able to initialize and display characters onto a 16x2 LCD character mode module. It is also possible to make a circuit out of logic gates that could take the output of a standard matrix keypad or even a PS2 type keyboard and route that keyboard data to the LCD module. The big thing to think ...


14

Positioning the polarizers and alignment layer in a TN display at 45° and 135° can help improve viewing angle performance. By doing this, the angles of best contrast are placed in the display's horizontal plane. This has to do with the asymmetric shape the liquid crystals assume in a TN display. From: 3M Optics 101. While all the videos are informative (...


14

A LED/LCD display is constructed of multiple panels: 16x16, 64x64, etc depends on the supplier. These panels are mounted such to produce the 1920 x 1080 pixels Each panel will have its own interface IC and LED/LCD driver chipset like the tlc59283 How is each panel/module controlled? via a serial interface. If you look at a 320x240 panel such as this one ...


13

Typically there are long skinny driver chips for row and column. They may be on the outside COF (Chip-On-Flex) or inside COG (Chip-On-Glass construction) the panel itself. Here's an HD TV panel from Dave Jones' blog showing the COF column drivers: Here you can find a datasheet for a Novatek driver chip showing the data interface for 384 outputs- 128 x 3 ...


12

It's a 7-segments display. Unlike the dot-matrix character displays kevlar refers to these are most often not intelligent module. Most dot matrix displays have an HD44780-compatible controller which you simply can write ASCII codes to, but a 7-segment LCD will often be just the glass, with connections for segments and a number of backplanes (often up to 4). ...


12

You have to prevent any other device from driving the SPI lines during programming. To avoid driver contention, a series resistor should be placed on each of the three dedicated lines if there is a possibility that external circuitry could be driving these lines. Take a look at Application note AVR910. To avoid problems, the In-System Programmer ...


12

I asked an LCD maker or two about this. It's possible, if you have the money to spend. I note that the Nest thermostat (where they did have plenty of money to spend) appears to be a masked square LCD with a bezel and crystal that give the illusion of a round LCD display.


12

It's called "zebra strip", and yes, the black areas are conductive while the white areas are insulating. The strips do not need to line up one-for-one with the contacts on the board and the glass, as long as there is at least one for each connection (usually several) and there's enough space between the contacts so that they don't get bridged by a black zone....


12

The black metal bezel around the LCD glass is what connects to those bent fingers. The bent fingers either capture the LCD circuit board in place from its edges or the fingers extend through slots in the LCD circuit board. You can carefully bend the finger tabs straight and this will permit removal of the bezel. Once free the LCD glass will be able to be ...


10

It has 8 data pins. The 8-bit mode is the standard mode, because the data is 8-bit: the characters are ASCII, and the DDRAM addresses are also 7 bit wide. In 8-bit mode you write them in 1 instruction, in 4-bit mode you have to split a byte in 2 nibbles, shift one of them 4 bits to the right, and perform 2 write operations. 8-bit mode is just more simple. ...


10

The back light is being powered from the supply to the LCD controller - Pins 1 & 2, this is from the solder blobs marked JI & KI near R9. To run the back light from pins 15 & 16 you need to unsolder the JI & KI blobs first, then solder the JA or JK links If you want pin 15 to be +5v use both JA links (pin 16 will be ground) If you want pin ...


10

You shouldn't power anything from a voltage divider since the output voltage will fluctuate greatly with the amount of current sourced. Rather you should look into a step down voltage regulators. They're inexpensive and will easily triple your battery life.


10

The closest thing I can think of to what you're describing is an LCD light valve. It's a single piece of LCD glass with two electrodes on it. If you've ever used a self-darkening welding helmet, this is what's used to make the window in those. Most of these will probably be bigger than what you have in mind, though. If you plan on manufacturing this product ...


10

Yes, even LEDs do not have an infinite lifetime. However, when run at a low enough power such that they do not heat up much a lifetime of 50000 hours can be expected. 50000 hours when operated 24 hours a day every day is about 6 years. If the LEDs operate under warm or even hot conditions this lifetime will reduce dramatically. But since you were using the ...


10

That "silver rectangle" is the LCD driver chip. The silver color is the back of the chip-die which is made of silicon The function of that LCD driver chip is to take some input signals and drive many outputs which connect to the LCD. Without the LCD driver all these lines would have to be connected over the connector making that connection unreliable as ...


9

If you are asking how to make a font, there are a number of utilities out there. Here are a few: DotFactory is simple, free, and does a good job converting existing font files to C code. BitFontCreator is a low cost tool with a graphical font editor, you can convert and edit existing fonts or draw your own fonts and symbols. Very versatile. I like it and I'...


9

I do want to encourage you. Ahh, this brings back so many happy memories of my childhod, learning to program. This was before the days of the internet of course, so practically everything had to be invented on the fly. One of the things I figured out how to do was handle tiny bitmapped fonts. Then I realised that, if I gave each character as much space as ...


9

As others note it's a "zebra connector" which conducts through the plane of the rubber but not across it (ie in the directions you'd expect for it to work). The 'pitch' of the band s of conduction/non conduction are finer than the pitch of the contacts concerned so that short circuits are not formed between the contacts when the strip is moved "sideways". ...


9

The explanation by drivers99 is correct. Noise is generally coming from capacitors or from the AC to DC converter. Do you remember the old style cameras? They had a flash that used to make a whining noise after every photo taken. That's the capacitor charging. Same thing with your monitor. Why does it make that sound only in some patterns? Due to pixel ...


9

Seems to be what NEC refers to as VIT, Value Integrated TFT Technology. Alternatively known as SoG, System on Glass. They differentiate it from Chip on Glass or Chip on Film/Tape. But the tech isn't that old. A press release shows maybe 2007. Due to the high electron mobility of the low-temperature polysilicon used in VIT technology, high-speed ...


9

Zebra strips are most often custom made to size to suit the enclosure design requirements of a product designer. This is why it can be hard to find general purpose replacements. Using the following drawing as a reference: Dimension H between the circuit board and the LCD glass is the most critical dimension. Proper operation normally requires the material ...


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