positive lcd display free sample

LCD (Liquid Crystal Displays) have two options or display modes.Positive mode (dark characters on a light colored background) and negative mode (lighter colored characters on a darker background).

Please see Fig.1: Yellow green STN (Super Twisted Nematic) display, the background of yellow green is lighter than dark blue characters. It is a positive mode. Fig. 2 is a blue STN display, its background of blue is darker than the white characters.It is negative mode.

Positive mode displays have the advantage of their lighter background and no backlights are needed. They normally use transflective or reflective polarizers and have lower power consumption. They can be seen with ambient light.

Negative mode displays need backlit in order to be seen. They normally use transmissive polarizers. They have better contrast and wider viewing angles in the indoor dim environment. The readability is much better than positive displays.

But under bright ambient light or even under direct sunlight, the displays will be easily washed out. In order to be seen under the bright surrounding light, the backlight brightness has to be increased to over 800 nits. The sunlight readable displays consume much power.

Of course, we can always use LED backlight in the LCD module with fewer LED chips and turn off LED backlight when not use to save power. When can also add transflective polarizer to some negative LCDs to make it sunlight readable, but the contrast will be compromised.

Positive and negative mode concept is not only limited to monochrome LCD displays (LCD panels, character LCDs, graphic LCDs etc.), it also uses for color displays, or even other display technologies.  We will categorize the displays as below,

Character LCD modules (Alphanumeric LCD display modules) with character sets: 8×1 LCD display, 8×2 LCD display, 16×1 LCD display, 16×2 LCD display, 16×4 LCD display, 20×2 LCD display, 20×4 LCD display, 24×2 LCD display, 40×2 LCD display, 40×4 LCD display. COB (Chip on Board) bonded, 4 or 8 bits parallel, SPI, I2C interface

Graphic LCD modules with dot matrix sets 122×32, graphic LCD display, 128×64 graphic LCD display, 192×48 graphic LCD display,192×64 graphic LCD display,240×64 graphic LCD display,240×128 graphic LCD display,240×160 graphic LCD display with different color LED backlights, with COB and COG (Chip on Glass) assembling technologies

Monochrome and Color Graphic OLED modules with dot matrix sets 128×32 graphic OLED display,128×64 graphic OLED display, 128×96 graphic OLED display, 160×128 graphic OLED display, 128×128 graphic OLED display, 256×65 graphic OLED display

Full Color TN and IPS displays with panel sizes: 1.3”IPS display, 1.44” TN display, 1.5” IPS display, 1.77”TN and IPS displays, 2.0” TN and IPS displays, 2.2” IPS display, 2.35” IPS display, 2.4” TN and IPS displays, 2.8” TN and IPS displays, 3.5” TN and IPS displays, 4.3” TN display, 5.0” TN and IPS display, 7.0” TN and IPS display, 10.1” IPS display with medium and high brightness (sunlight readable), with parallel, SPI, RGB, LVDS, MIPI interfaces.

As we know, LCD screen is a negative display which can’t emit light on its own. It either relies on ambient light or uses LED backlight in the back as a light source. We divide LCD screen intotransmissive LCD, reflective LCD, and transflective LCDaccording to the employing mode of light. Also, we divide LCD screen into the positive display and negative display according to the light of the background part.

It is very simple, but most people can’t fully understand the meaning. We already introduced the difference between TN, HTN, STN and FSTN LCD in my previous post. The offset angle of liquid crystal in TN LCD is 90 degrees. What is that? If we see TN, HTN, STN and FSTN LCD in the perspective of view angle, it is much easier for us to understand.

Normally, it would be 6:00 o’clock direction or 12:00 o’clock direction. 6:00 o’clock direction means that we can see it clearly from the frontage and 6:00 o’clock direction. We can still see it clear from 3:00 or 9:00 o’clock direction if we make it well enough even it is 6:00 o’clock direction. The digital clock display in a car is installed on the right-hand side of the driver, which is usually 9:00 o’clock direction.

For example: if the view direction of TN LCD is 6:00 o’clock direction, you will see the graphic very blurred at any angle of 3:00 o’clock or 9:00 o’clock direction. We can still see it clearly within 20 degrees of 3:00 o’clock or 9:00 o’clock direction if it is 6:00 o’clock direction HTN LCD.

An import function allows additionally to use Windows fonts. With the FontEditor it is easy to generate for example Cyrillic, Greek and Arabic fonts. The preview function shows immediately the size and style in simulation window. When the testboard EA 9780-2USB is connected to the USB port, you can see the character (or any predefined text) live on the display which is plugged-in!

Liquid Crystal displays or LCDs have been used in electronics equipment since the late 1970s.   LCD displays have the advantage of consuming very little current And they are ideal for your Arduino projects.

In this article and in the accompanying video I’ll show you how easy it is to add an LCD display to your next Arduino design. I’ll also show you a very popular Arduino Shield that has a keypad which you can use in your projects as well.

Today LCD displays are used in a variety of items from test equipment to televisions. They’re inexpensive and versatile, this makes them ideal for all sorts of designs.

LCD displays do not emit light. Instead they block the passage of light, like little windows which open and shut the let light through. The liquid crystals used inside LCD displays are sandwiched between two layers of polarized material. By changing the orientation of the liquid crystals they allow light to pass or they block the light entirely.

Because transmissive LCD displays (the type we will be using) work by blocking light they require a backlight. Several methods have been used to create back lights including electroluminescent panels and fluorescent tubes.   these days the most common form of backlight is an LED, in fact so-called LED televisions are usually just LCD screens with an LED backlight system.

Another type of LCD display, the passive-matrix display, does not require a backlight, it works using reflected light. This type of display is often found in digital watches.

The principles of liquid crystals were discovered in the late 1880s but work on Modern LCD displays did not begin until the mid-1960s. a number of patents were filed in the early 1970s and in 1973 the Sharp Corporation introduced LCD displays for calculators.

The first color LCD displays were developed in the early 1980s but production units were not commonly available until the mid-1990s. By the late 1990s LCD displays were quite common.

A number of LCD displays are available for experimenters. These low-cost monochrome displays are ideal for use with microcontrollers like the Arduino and micro computers like the Raspberry Pi.

These displays are available in a number of different configurations. The part number for the display generally relates to the number of rows and columns in the display.

Common display configurations include 16 x 2, 16 x 4 and 20 x 4.  All of these displays are used in a virtually identical fashion the only difference being the number of columns and rows they have.

The LCD1602 display module is a very popular and inexpensive LCD display.  It is available in a number of different colors such as blue yellow and green and can easily be connected to an Arduino or Raspberry Pi.

In operation data is sent down the parallel data lines for the display. There are two types of data that can be sent to the display. The first type of data are the ASCII characters which are to be displayed on the display. The other type of data are the control characters that are used to activate the various display functions.

Brightness– This is the input for the brightness control voltage, which varies between 0 and 5 volts to control the display brightness. On some modules this pin is labeled V0.

Because the LCD module uses a parallel data input it requires 8 connections to the host microcontroller for the data alone. Add that to the other control pins and it consumes a lot of connections.  On an Arduino Uno half of the I/O pins would be taken up by the display, which can be problematic if you want to use the I/O pins for other input or output devices.

We will begin our experiments by hooking up the LCD1602 to an Arduino Uno and running a few of the example sketches included with the Arduino IDE.  This will allow you to get familiar with the display without needing to write any code.

We need to hookup our LCD display to our Arduino. The display can use any of the Arduino digital I/O pins as it has no special requirements, but if you hook it up as I’ve illustrated here you can run the example sketches without needing to make any modifications.

In addition to the LCD1602 display ands the Arduino Uno you will need a 10K trimpot ot potentiometer, this is used a s a brightness control for the display. You’ll also need a 220 ohm resistor to drop the voltage for the displays LED backlight.

The sketch starts with a number of credits and a description of the required hardware hookup. You’ll note that this is the same hookup you just performed on your Arduino and LCD module.

We then initialize an object that we call “lcd” using the pinouts of the LCD display. If you decide to hook up your display to different pins then you’ll need to modify this section.

Load the sketch up to your Arduino and observe your display. If you don’t see anything try adjusting the brightness control that you wired to the display.

The second example we will try isthe Scroll sketch. Scrolling is a useful technique when you can’t get your text to fit on one line of the LCD display.

In the loop the code demonstrates the use of thescrollDisplayLeftandscrollDisplayRightfunctions.  As their names imply they move the text in a left or right direction.

Finally the last counter moves the text 16 positions to the left again, which will restore it back to the center of the display. The loop then repeats itself.

Custom characters are useful when you want to display a character that is not part of the standard 127-character ASCII character set. Thi scan be useful for creating custom displays for your project.

A character on the display is formed in a 5 x 8 matrix of blocks so you need to define your custom character within that matrix. To define the character you’ll use thecreateCharfunctionof the LiquidCrystal library.  You are limited to defining a maximum of eight characters.

As with the previous sketches we examined this one starts by loading theLiquidCrystallibrary and defining an object calledlcdwith the connection information for the display.  It then moves on to define the custom characters.

The last two arrays,amsUpandarmsDowndefine the shape of a little “stickman”, or “stickperson” if you want to be politically correct! This is done to show how we can animate a character on the display.

Finally the setup routine ends by printing a line to the first row of the LCD display. The line makes use of two of the custom characters, the “heart” and the “smiley”.

One thing you may have noticed about using the LCD display module with the Arduino is that it consumes a lot of connections. Even in 4-wire mode there are still a total of seven connections made to the Arduino digital I/O pins. As an Arduino Uno has only 14 digital I/O pins that’s half of them used up for the display.

But there is another solution. Use the I2C bus adapter for the LCD display and connect using I2C.  This only consumes two I/O pins and they aren’t even part of the set of digital I/O pins.

The I2C Adapter for the LCD display is a tiny circuit board with 16 male header pins soldered to it. These pins are meant to be connected directly to the 16-pin connection on the LCD1602 display (or onto other displays that use the same connection scheme).

The device also has a 4-pin connector for connection to the I2C bus. In addition there is a small trimpot on the board, this is the LCD display brightness control.

Load this sketch into your Arduino then open your serial monitor. You’ll see the I2C address of your I2C LCD display adapter. You can then make note of this address and use it in the sketches we’ll be looking at now.

On the next line we define the connections to the LCD display module from the I2C Adapter,. Note that these are NOT the connections from the Arduino, they are the connections used by the chip on the adapter itself.

In setup we set the size of the display and then print “Hello world!” on the first line in the first position.  After a short delay we print “How are you?” on the second line.

The sketch is similar to our demo sketch in that it creates an “lcd” object with the I2C and display connection information.  It also defines a couple of parameters for the DHT22 sensor, as well as some floating variables to hold the temperature and humidity values.

Note that this displays the temperature in Celsius. If you want to change this to Fahrenheit its a simple matter of using some math. The formula( temp * 1.8 ) + 32will convert the results to Fahrenheit.

So far we have used the LCD1602 display module for all of our experiments. For our final demonstration we’ll switch to a popular Arduino shield that contains a LCD1602 along with some push buttons.

The LCD Keypad Shield is available from several different manufacturers. The device fits onto an Arduino Uno or an Arduino Mega and simplifies adding an LCD display to your project.

Note that the LCD is being used in 4-wire mode. The LCD itself is the same one used on the LCD1602 module, so all of the code for that module will work with the LCD Keypad Shield as well.

Now that you know how the LCD Keypad module works and which Arduino pins it uses all that remains is to install it onto your Arduino and load the demo sketch.

Use a shield that exposes the pins for prototyping before you install the LCD Keypad shield. In the video associated with this article I use a “Screw Shield” that brings all of the Arduino I/O pins out to a series of screw connectors. There are other similar shields. Using one of these shields is the easiest way to work with the LCD Keypad shield, as well as other Arduino shields.

The sketch begins by including theLiquidCrystallibrary. You can use the original one or the one includes with theNewLiquidCrystallibrary.  We then set up an object with the LCD connections, note that these are just hard-coded as they won’t change.

After that we define a function calledread_LCD_buttons().  This function reads the value on analog port A0 and returns an integer corresponding to the button integers we defined earlier. Note that the function adds approximately 50 to each of the manufacturers specified values to account for intolerances in the resistors in the voltage divider.

We start the loop by placing the cursor 9 spaces over on the second line. We then use themillisfunction to display a counter that counts the time since the Arduino was reset. This is to test the Reset button.

We then call ourread_LCD_buttons()function and use it to display the value of the push button, right before the counter. Then we end the loop and do it again.

As you can see LCD displays are pretty simple to use thanks to the availability of some excellent libraries for the Arduino.  As these displays are also very inexpensive they will make an ideal addition to many of your Arduino projects.

And finally the LCD Keypad Shield is a convenient method of adding both a display and a simple keypad to your project, no wiring or soldering required.

We come across Liquid Crystal Display (LCD) displays everywhere around us. Computers, calculators, television sets, mobile phones, and digital watches use some kind of display to display the time.

An LCD screen is an electronic display module that uses liquid crystal to produce a visible image. The 16×2 LCD display is a very basic module commonly used in DIYs and circuits. The 16×2 translates a display of 16 characters per line in 2 such lines. In this LCD, each character is displayed in a 5×7 pixel matrix.

Contrast adjustment; the best way is to use a variable resistor such as a potentiometer. The output of the potentiometer is connected to this pin. Rotate the potentiometer knob forward and backward to adjust the LCD contrast.

A 16X2 LCD has two registers, namely, command and data. The register select is used to switch from one register to other. RS=0 for the command register, whereas RS=1 for the data register.

Command Register: The command register stores the command instructions given to the LCD. A command is an instruction given to an LCD to do a predefined task. Examples like:

Data Register: The data register stores the data to be displayed on the LCD. The data is the ASCII value of the character to be displayed on the LCD. When we send data to LCD, it goes to the data register and is processed there. When RS=1, the data register is selected.

Generating custom characters on LCD is not very hard. It requires knowledge about the custom-generated random access memory (CG-RAM) of the LCD and the LCD chip controller. Most LCDs contain a Hitachi HD4478 controller.

CG-RAM address starts from 0x40 (Hexadecimal) or 64 in decimal. We can generate custom characters at these addresses. Once we generate our characters at these addresses, we can print them by just sending commands to the LCD. Character addresses and printing commands are below.

LCD modules are very important in many Arduino-based embedded system designs to improve the user interface of the system. Interfacing with Arduino gives the programmer more freedom to customize the code easily. Any cost-effective Arduino board, a 16X2 character LCD display, jumper wires, and a breadboard are sufficient enough to build the circuit. The interfacing of Arduino to LCD display is below.

The combination of an LCD and Arduino yields several projects, the most simple one being LCD to display the LED brightness. All we need for this circuit is an LCD, Arduino, breadboard, a resistor, potentiometer, LED, and some jumper cables. The circuit connections are below.

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At the heart of every great digital signage display is this: content. Make it look good and people will stop to look at it. Make it look bad or outdated, and chances are they won’t be looking at your screen again.

Walls.io offers a unique feature to showcase sponsored ads from brands you partner with. This feature is called Sponsored Posts, and they are special posts on your social wall that aren’t filled with regular social content from your sources. Instead, you can upload specific images (or videos or just text) that you want to display there and have it show up on your wall in regular intervals.

If you need to create a quick notice, perhaps detailing a room change or a meeting time, there are a wealth of apps to make that happen. Like Noticeboard - an app that can be found in the ScreenCloud App Store. It allows you to create a quick and easy display in seconds, and also allows for real-time edits.

This type of content works well as ‘filler’ content in between video, ads and social media displays to stop your viewers from getting digital-overload.

Food is such a big part of our lives, it’s natural that we’re drawn to images, descriptions and menu boards showing it. Enter the digital menu board digital signage display.

This is one of the most important content displays you’ll create if you work in a restaurant, fast food chain or bar. It also works in an office cafeteria, an event setup or even as a fun noticeboard where you can swap menu items out for things you’re working on or fun descriptions of your team members. If you’re a franchise, this works especially well as you can change the price of an item across all screens and locations from one ScreenCloud login.

Screens are great for all of the good stuff we like to put out into the world, but they’re also a good vehicle when you need to make an emergency notice that needs to reach a lot of people. For (planned) fire drills, you can schedule the alert to pop up on your screens, otherwise, have a template at the ready to push live should you need to display it in the moment.

Have you ever been at the car wash in the late afternoon, struggling to read the instructions on the display at the pay kiosk? That may be because it was not a sunlight-readable LCD display.

Any character or graphic LCD (not TFT, we will get to that in a bit) that is “positive mode” will be sunlight readable. Positive mode displays will have dark letters on a light background.

For any questions about Crystalfontz LCD product lines, what LCD is the best choice for your application, or any other questions (technical or availability), please contact our knowledgeable and friendly support staff via email, phone, or chat.

As the saying goes, a picture is worth a thousand words... so to illustrate the differences between the positive mode LCD and negative mode LCD see the image below.

Positive mode LCD means that the letters/characters are dark colored and the background color is light. This mode of LCD will operate with and without a backlight.

Negative mode LCD means that the letter/characters are light colored and the background is dark. Negative mode LCD’s must have a backlight ON to operate.

We offer three types of monochrome LCD’s: Character LCD, Graphic LCD and Segment (Static) LCD. All three of these displays can operate in both negative and positive mode. Any of the three types of displays above can run in negative mode for TN, STN and FSTN.

Static displays do not normally contain a backlight. If you wish to use this type of display in negative mode, please notify us that you will need a backlight. Many times the backlight for a static display may need to be customized.Focus displays offers Character LCD modules (aka alphanumeric LCD display or LCD monochrome display) in the following configurations: 8x1 LCD display, 8x2 LCD display, 16x1 LCD display, 16x2 LCD display, 16x4 LCD display, 20x2 LCD display, 20x4 LCD display, 24x2 LCD display, 40x1 LCD display, 40x2 LCD display, 40x4 LCD display.

Focus displays offers Segment LCD Displays (aka static displays glass and numeric LCD displays) in the following configurations: 7 (seven) segment LCD display, 14(fourteen) segment LCD display, 16(sixteen) segment LCD display,

Character LCD Displays (aka Alphanumeric) are one of the most common display technologies available and for that reason we hold inventory for samples and prototypes in our Chandler, Arizona location.

These displays have been in use for many years, and in some ways the technology has become a commodity, but it is important to select the best options to fit your design. There are many details concerning this technology, including: fluid type, operating voltage, controller/drivers and other key details that can make your design excel or under-perform.

Our team of LCD specialists can assist you in selecting the best options so that your design is able to meet your needs and at a cost that is within your budget. Call today with any questions.

These displays are used in applications such as change machines, measurement devices, and data loggers. The module has the ability to display letters, numbers and punctuation marks.

One reason for the popularity of Character LCD displays is that they are equipped with a controller/driver chip containing a built in character (or font) table.

The table holds preloaded letters, numbers, and punctuation for each language. The font table allows the designer to request any character by addressing (selecting) the number of that character. In other words, the letter capital ‘T’ may be assigned the number 31 and the “&” symbol could be assigned number 141. This eliminates the work required to create each charter from scratch and reduces the amount of time necessary to program the LCD module.

The LCD you choose for your new design sets the perceived value of your product. Think about it: The first thing your customer looks at when they are deciding whether to purchase your product, is the LCD display. If it looks good, then your product looks good.

Negative mode displays are popular for new designs since they stand out. Negative mode means the background is a darker color, like black or blue and the characters/icons/segments are a lighter color such as: White, Red or Green.

The opposite of a negative mode is positive mode where the background is a lighter color such as yellow/green or grey and the characters/icons/segments are a darker color like black or dark blue.

Negative mode displays must have a backlight on all the time to be readable. The challenge is that the LED backlight will draw/drain 10 times more power than the LCD without a backlight. So, if this is a battery application, it is best to stick with a positive mode.

Positive mode displays are readable without a backlight if there is enough ambient light. The LCD without a backlight will draw around 1uA. LED backlights can draw as little as 15mA up to 75mA or more depending on the number and brightness of the LEDs.

The first question to answer is ‘what size of LCD?’ The larger the display the more information that can be displayed and the larger the characters can be. We recommend you choose one of the standard sizes on this page to reduce cost and lead time. Focus Display Solutions (aka FocusLCDs) carries many of the industry standard sizes in inventory and may be able to ship the same day.

Character LCD Displays are built in standard configurations such as 8×1, 20×2 and 40×4. The two numbers identify the number of characters in each row and then the number of rows. An example of this is a 20×2 which means there are 20 characters in each row and there are two rows. This will provide you a total of 40 characters. The more characters there are on the display, the more drivers are required to drive the LCD. The controller and drivers are included with the LCD.

Note: It is possible to program the software to scroll your letters and numbers across the screen, allowing you to choose a smaller sized LCD and still display all your information.

The cost of character displays is driven more by the size of the glass, then by the number of characters. A larger 8×1 can be more expensive than a small 16×2.

It is possible to custom build a unique combination such as a 12×2 or a 16×8. This would be considered a custom LCD and would require a one-time tooling cost and possibly a higher MOQ. Go to our

Character LCD modules are available in two temperature ranges, Normal (for indoor use) and Extended (for outdoor use). The outdoor version will continue to operate down to -30C. The cost difference between normal and wide (extended) temperature range is 5% to 7% higher for the extended versions. In most cases, if cost is not critical, we recommend that you incorporate the wider temperature version.

There are three types of backlights available for a character LCD module: No backlight; LED; or EL backlight. Before introducing the various backlight options, it is helpful to cover two terms that are common for backlights: NITs and half-life.

Engineers designing a battery powered product may request a character module with no backlight since the backlight draws more than ten times (10x) the power required for the LCD alone. The goal with a battery powered product is to conserve power and extend the life-time of the battery.

If the product needs to be readable in the dark or low light conditions, then it will be necessary to attach a backlight of one type or another. The best way to conserve power is to keep the amount of time the backlight is on to a minimum. Turn off the backlight as soon as the user no longer needs it. This is a common practice in cell phones. The backlight turns off a few seconds after the number is dialed or the phone is answered. The person using the phone will continue to talk, but the display will be dark.

DC Current – LEDs are driven by DC (Direct Current), which is the same type of power required for the character LCD logic voltage. Also, batteries supply DC which makes it easy to integrate the LED backlight with a battery. EL backlights require an AC (Alternating Current) to operate. The AC signal needs to be generated by an inverter. The added inverter increases the cost of the display and produces electrical noise that can interfere with neighboring circuits.

Character LCDs that include an EL (ElectroLuminescent) backlight are not as common and their popularity is decreasing. EL backlights are AC driven which requires an inverter to be supplied by the customer or attached to the LCD. Their half-life is rated at 3K hours which makes this a poor choice for products where the backlight will be on all the time. Their MOQ (Minimum Order Quantities) have increased in the last few years. At this time there is a 500 piece MOQ.

There are some key advantages to EL backlights. They are very thin, around one to two millimeters in thickness. And they provide a very even flow of light. We carry inventory on a few EL character displays, but the majority of the character displays we sell are LED.

A character LCD is constructed by placing the nematic fluid between two layers of ITO (Indium tin oxide) glass. The function of the fluid is to either block or allow light to pass through.

A TN (Twisted Nematic) monochrome LCDs is the lowest cost option. TN does not provide a very sharp contrast and has a smaller viewing angle then STN or FSTN. A smaller viewing angle means the display is readable if you look directly at it, but if you rotate it more than 40 degrees in either direction, the characters will be difficult to read.

STN (Super Twisted Nematic) fluid is the most popular option. It provides a sharper contrast and a wider viewing angle than TN. Below is a photo of a STN 16 x2 character display.

FSTN monochrome character LCD displays are assembled by taking the STN fluid and adding a film or retardation coating to the glass. This produces a sharper contrast than STN. FSTN is more popular on higher end products such as medical applications. Below is a photo of a FSTN 16×2 monochrome LCD

There are three types of polarizers: Reflective; Transflective; and Transmissive. The correct polarizer is determined by the various lighting conditions your character LCD display will operate in.

The job of the polarizer is to allow some light to pass through and some of the light to be reflected. Depending on where your display will be operating, will decide which polarizer to choose. There is no cost difference between the three polarizers. Below is a quick summary:

The reflective polarizer is basically a mirror. It will reflect 100% of the ambient light and is ideal for displays operating in direct sunlight or in situations with very bright indoor lights.

A reflective polarizer cannot be used with a LED backlight or EL backlight since it will not allow any of the light to pass through, but it is possible to use with a LED edge-lit or side-lit display. An advantage of an edge-lit display is that it is thinner than a LED backlight, but not as thin as a display equipped with an EL backlight.

A Transflective polarizer is the most popular of the three options and works best with a display that requires the backlight to be on some of the time and off some of the time. It does not perform as well in direct sunlight as a reflective polarizer, but is sufficient in most cases.

The Transmissive polarizer is used when the backlight is on all the time. This is not the best option for battery powered products, but provides a brighter backlight. This polarizer must be used for displays that run in negative mode. Negative mode is when the characters are light colored and the background is a dark.

V Logic is the voltage used to drive an LCD and draws very little current, somewhere around 1mA or less. Character displays can be driven with a VL at 3.3V or 5V.

V LED is the voltage used to drive the LED backlight only. This can be 3.3V or 5V. LED backlights can draw up to ten times (10X) the amount of current of just the LCD alone (VLCD). If your product is a battery application, the backlight should be turned off when not in use. Or build in a sensor that only turns it on in the dark.

Is it possible to drive the LCD and the LED backlight from the same connection, but not recommended since interference from the LED backlight could affect the performance of the LCD.

A key advantage of character LCDs over multicolor technology such as TFT (Thin Film Transistor) and OLED (Organic Light Emitting Diodes) it their low thirst for current.

TFTS and OLEDs require power to generate light to be readable. In many cases, their backlight needs to be even brighter in direct sunlight. This could draw 50mA or more depending on the size and brightness of the display.

When the ambient temperature of the display drops too low, the display’s performance suffers. The colder the fluid in the display, the slower the response. At some point, the display freezes up and the characters no longer change.

As long as the temperature doesn’t drop too low, there will be no damage to the display, and it will return to normal operation when the temperature rises.

This is a much more affordable solution. A small PCB (Printed Circuit Board) is attached to the back of the LCD. The board is populated with several quarter watt resistors in series that generate heat. This option draws a great deal of power. In fact, it draws more than most LED backlights.

Believe it or not, LEDs do generate heat, but nothing close to resistors or heater film. In some cases, it is enough to give the display a little extra warmth to keep it operating when the temperature drops below its threshold.

Nothing saves heat and power like insulation. Putting your LCD into something that breaks the wind and holds in the heat, will save your batteries. Many times, a protected display will continue to operate even when the temperature drops far below the threshold. This should always be the first step taken when worrying about display functionality at low temperatures. Once your product is insulated, the heat producing options noted above can be implemented.

There are three fluid types used in character LCDs: TN, STN and FSTN. TN operates the best at colder temperatures and offers a faster response time. TN does not provide the wide viewing range found in STN and FSTN, but is sufficient for most industrial uses.

The five most common types of LCD technology are: Segment, Character, Graphic, TFT and OLED. Character and Segment are the least likely options to be discontinued. They have been around for many years and are still very popular.

The displays are made up of small squares that contain a 5x8, 7x10 or 16x16 dot matrix configurations. That means there are 5 dots across and 8 dots up for a total of 40 dots. Each dot is individuality addressed on or off to produce any letter or number.

Used to read or write the data being transferred between the LCD and the microprocessor. Tie this to ground if you only plan to write data for one-way communications.

DB 0. Most character LCDs have eight (8) data bits for faster transfer. But can operate on just four (4) data bits if you are running low on I/O (In/Outs) pins.

Positive connection of the LED backlight or side lit. The voltage could range from 5V or 3.3V. Not all character LCDs contain a LED backlight. In this case, the two pins are no connect.

Polarity is an issue with LED backlights, since they are DC (Direct Current). That means positive must connect to positive. Half of the character LCDs have pin 15 as positive and 16 as ground. The other half are reversed. If you need the polarity reversed, there is a jumper on the back of the PCB to switch polarity.

This page contains a partial list of our standard displays. Simply choose the number of characters, the size of the display and the color combination that will meet your needs. If you need a size not listed on this page, please call us. We can still supply it to you.

Our lead time on standard Character LCD displays – that are not in stock – range from five to seven weeks. This rapid lead time is due to the fact that we do not ship LCD’s via boat, but FedEx Air. By shipping via FedEx Air, we receive the LCD glass within four to five days after it is completed, compared to shipping by boat which can add several additional weeks to your lead time.

Don’t see the exact display you want on this page? Focus Display Solutions can supply you a display to match the exact configuration you want, even if it is not in our current inventory.

The cost to design and tool up a custom replacement LCD is much less than the cost associated with retooling a case or having to redesign the customer’s PCB to accept a different LCD. The customer may also need the exact display to repair units that are in the field.

This custom character design allows the customer to avoid any redesign cost or delays in the manufacturing of their product and to offer replacement displays for products that had been in the field for over ten years.

Character LCD displays are built in standard sizes and configurations. This makes the process of locating an equivalent LCD a simple process, but it is critical to make sure that the replacement display is a drop -in equivalent to your current display. It may not be possible to build a 100% equivalent product without some modifications.

We are able to match and replace these discontinued Liquid Crystal Displays. There may be a one-time NRE (Non-Recurring Engineering) fee required to modify the ITO glass, PCB (Printed Circuit Board) and bezel to match the dimensions and characteristics necessary for your production.

If your current LCD supplier has discontinued your display, Focus Display Solutions (aka Focus LCDs) has the ability to cross it over to an equivalent display and in many cases Fed Ex/UPS a sample to you the same day.

Note: when you begin ordering LCD displays from Focus, we will supply you with the data sheet. If you purchase the display, you should own the data sheet.

Providing us the full part number of the LCD allows us to determine not only the size of the display, but also the type of construction such as COB (Chip on Board) or COG (Chip on Glass), number of characters, backlight option, operating temperature range, background and backlight colors, viewing angle, backlight and LCD logic voltage, and in most cases the controller driver used.

With the part number, we will attempt to locate a full data sheet with enough details allowing us to quote a replacement for your discontinued display. If we cannot locate a data sheet, we will ask if your previous supplier had provided one to you.

If we are unable to locate the data sheet of your current LCD, we will request a data sheet. If possible, please forward over the data sheet or a link to the data sheet. If your LCD supplier is no longer in business or they will not provide you the data sheet, the next option is a photo of the display.

If you decided to move forward with us and order samples of your replacement display based on the estimated cost, we will require two of your discontinued samples. They do not need to be working displays, but need to be in good condition. Please note: We will not be able to return the two displays.

Note: when you begin ordering LCD displays from Focus, we will supply you with the data sheet. If you purchase the display, you should own the data sheet.