7 Segment Display

Product Details

Product Introduction

With seven LEDs(if a decimal point is required, then it's eight LEDs), it makes up a 7 segment display. Jinhua specialized in supplying a series of 7 segment display from 0.25”to 5”with all kinds of colors, common cathode and common anode circuit. We produce all SMD LEDs inside the diaplays by ourselves. Integrating several 7 segment displays can get panels and its size is up to its future application.

Product Parameter

Product application

Display time and digital combination

Home and smart appliances

Industrial and instrumental applications

Packing & Lead time

1. Packing (choose anyone you like):

1-1 Using EPE foam and paper carton

1-2 Using blister box and paper carton

1-3 Using tube and paper carton

2. Lead time:

• 2-10Kpcs: 7-10 working days

• 10.1-50kpcs: 10-15 working days

• Beyond 50kpcs: to be negotiated

Our Services

A. Any inquiried will be replied within 24 hours

B. Professional manufacturer

C. OEM/ODM service available

1) Customized panel display/design available;

2) Packaging design offered;

3) You think it , we make it!

FAQ

1. How is luminance differ from luminous intensity?

Luminous intensity means, for example, the brightness emitted through a lamp LED in total, in spite of the light source’s area. Brightness is the brightness of the entire area (for example, a display device). If the source area are brighter, the brightness would be higher. Usually, by dividing the luminous intensity by the light source’s area to obtain brightness.

2. Is it possible to do reflow soldering for all LED segment displays?

For most LED displays, reflow soldering is not recommended. While there is only one exception which is the LF series, one of the surface mount displays. Here recommend to use dip or wave soldering for all other types (LA/LB/LAP/LBP). For further information, please refer to the respective data sheets.

3. Is it possible to do manual soldering?

Yes, but need to be careful, too much mechanical or thermal stress should not be applied to the leads, or it would affect the reliability. Please contact us for unusual cases if needed.

4. Would it be acceptable to activate LED displays with supplying a voltage directly?

Although it is possible, still not recommend. As we have seen above, a direct supplied voltage may result in an exponential change in output current to cause failure. Therefore, there should be a resistors connected to limit current.

5. Color temperature and brightness

Unit: absolute temperature (Kelvin, K)

The color temperature is expressed in absolute temperature K, which is to heat a standard black body (such as platinum). When the temperature rises to a certain level, the color starts to change from red, orange, yellow, green, blue, indigo (blue-violet), and purple, gradually Change, using this characteristic of light color change, when the light color of the light source is the same as the light color of the black body, we call the current temperature of the black body the color temperature of the light source. When the color temperature is around 3000K, the light color becomes yellowish. When the color temperature is above 5000K, the light color becomes bluish. Lights of different color temperatures have different lighting and visual effects. Different color temperatures correspond to different colors of light as shown below. Different wavelengths give human eyes different color perceptions, from red, orange, yellow, green, blue, indigo (blue-violet), and purple. The sensitivity of the eye changes strongly with the wavelength.

For example, under good lighting conditions, the eye's sensitivity to 550nm wavelength light (yellow light) is 20 times that of red or blue light. This is also an important reason why most car fog lights and street lights on roads use yellow light. Color temperature is a measure of color temperature, not the brightness of a lamp. The color temperature of the halogen lamp can be from 2300K to 7000K; the color temperature of the HID lamp is from 4200K to more than 8000K; the higher the color temperature of the lamp, the worse its penetration power to fog and rain (the less bright it is).

6. How to ensure the quality of the LED display

Anti-static LED display electronic display screen assembly factories should have good anti-static measures. Dedicated anti-static ground, anti-static floor, anti-static soldering iron, anti-static table mat, anti-static ring, anti-static clothing, humidity control, equipment grounding (especially the foot cutter), etc. are all basic requirements, and should be checked regularly with a static meter .

1. Drive circuit design The arrangement of the drive IC on the drive circuit board on the LED display module will also affect the brightness of the LED. Since the output current of the driver IC is transmitted too far on the PCB board, the voltage drop of the transmission path will be too large, which affects the normal operating voltage of the LED and causes its brightness to decrease. We often find that the brightness of the LEDs around the LED display module is lower than in the middle, which is why. Therefore, to ensure the consistency of the display screen brightness, it is necessary to design the driver circuit distribution diagram.

2. Anti-static LED display electronic display screen assembly factory should have good anti-static measures. Dedicated anti-static ground, anti-static floor, anti-static soldering iron, anti-static table mat, anti-static ring, anti-static clothing, humidity control, equipment grounding (especially the foot cutter), etc. are all basic requirements, and should be checked regularly with a static meter .

3. Mixed lights. LEDs of the same color and different brightness levels need to be mixed, or inserted according to the light insertion diagram designed according to the discrete law to ensure the consistency of the brightness of each color on the entire screen. If there is a problem in this process, the local brightness of the display will be inconsistent, which will directly affect the display effect of the LED display.

4. Design current value The nominal current of the LED is 20mA. Generally, it is recommended that its maximum use current is no more than 80% of the nominal value. Especially for displays with small dot pitch, the current value should be reduced due to poor heat dissipation conditions. . According to experience, due to the inconsistency of the attenuation speed of the red, green, and blue LEDs, the current value of the blue and green LEDs should be reduced in a targeted manner to maintain the consistency of the white balance after the display screen is used for a long time.

7. What causes the LCD display flicker?

Speaking of LCD display screens, you may first think of products such as mobile phones and tablet computers, but the use of LCD displays and far more than these. They are used in all walks of life as information output devices. As a key component, the quality of the LCD display directly affects the user's direct experience. What should I do if the LCD display screen flickers? What caused it? Today, the editor will give you analysis.

The LCD display refresh rate is incorrect. Many LCD displays require a standard 60 Hz refresh rate, but in fact, many LCD displays can only prevent phase doubt at 75 Hz. But some monitors happen to be the opposite, and users are better to try different settings. But remember, you can only choose between 60 and 75 Hz, and never exceed this limit.

LCD display aging sometimes shows the appearance of vibration due to the age of the display used. In order to check whether the electronic components inside the LCD display screen are aging, you can connect the faulty display to another person's computer for testing. If the fault still disappears, the display is broken and needs to be repaired.

8. Will OLED replace LCD?

1. From the perspective of technological development stage: LCD and OLED will coexist for a long time.

Modern new displays refer to flat solid-state displays (FPT) compared to traditional vacuum displays (CRT), mainly including liquid crystal displays (TFT-LCD), organic electroluminescent displays (OLED), plasma displays (PDP), inorganic thick Film electroluminescence display (TDEL), field emission display (FED), large-screen LED display, laser display, projection display, etc.

The earliest discovery of liquid crystal (LC) by humans can be traced back to 1888, and the discovery of organic electroluminescence (OLED) technology can be traced back to 1936. With the development of basic manufacturing technology, these two technologies can be applied in the field of electronic display.

At the end of the 20th century, in the fierce competition of display technology transformation, liquid crystal displays have overcome numerous difficulties, from weak to strong, defeating PDP, FED, and TDEL to stand out among many new displays and become the mainstream display in the new century.

The initial stage of the liquid crystal display industry's stormy capacity expansion stage has ended, and the industry has entered a technological upgrading stage with technological improvement as the core. In the next ten years, LCD displays will achieve major breakthroughs in system integration, power consumption and cost reduction.

TFT is an extension of large-scale semiconductor integrated circuit technology. With the development of science and technology, the technological development potential of TFT is huge, and amorphous silicon TFT is only its starting point.

It has become the biggest technical bottleneck restricting the sustainable development of liquid crystal displays. Instead, it is a wide-bandgap semi-oxide conductor. Its forbidden band width is about 3.7eV, which is completely transparent to visible light. Therefore, TFTs made of oxide semiconductors do not have the problem of aperture ratio, and the mobility of oxide TFTs It is much higher than amorphous silicon TFT, so the first step of using oxide TFT can fully meet the demand for high pixel density of 3D TV.

Compared with plasma and OLED, the power consumption of liquid crystal display is relatively low. However, the power consumption of LCD monitors still has huge room for reduction. At present, the utilization rate of light energy of the liquid crystal display is less than 10%.

Technically speaking, the use of oxide semiconductors, LED field sequential backlight technology, etc., is expected to increase the utilization rate of light energy of liquid crystal displays to more than 90%. Liquid crystal displays will become true energy-saving display products. In the future, 40-inch liquid crystal displays The power consumption may drop to about 10 watts.

The cost of liquid crystal display is mainly composed of backlight, color film, liquid crystal, polarizer, drive circuit, glass substrate, other materials and manufacturing costs (including equipment, plant, power, labor), etc. The cost of the six major components is as high as 80 %the above.

Through technological improvement, the color film and polarizer will be eliminated, and the drive circuit is expected to be directly integrated on the glass substrate. The application of electronic printing technology in the color film manufacturing process not only reduces costs, saves a lot of materials, but also enables liquid crystal displays. The manufacturing is more environmentally friendly. The current research on TFT electronic printing technology aims to eliminate the entire exposure process.

After the success of the three major technological innovations of system integration, field sequence backlight and natural light valve, LCD will become the cheapest display.

2. From the perspective of technological development trends: LCD and OLED will fade away

Now people say that OLED will replace the liquid crystal display. It is inappropriate to compare the advantages of OLED with the current liquid crystal display in the future.

The liquid crystal display itself is constantly improving, and OLED is also constantly improving. From a dynamic perspective, the progress and development of OLED and liquid crystal displays.

OLED and liquid crystal displays are not about replacing and being replaced. They are different varieties of new displays of the same generation, and they are a pair of sister flowers of new displays. They will continue to learn from each other and compete for development. Liquid crystal displays started from notebook computers, and OLED may make its mark on handheld terminals.

The most important driving force for the development of science and technology is material science. From the Stone Age to the Bronze Age, the Iron Age, to today's semiconductor silicon age, the progress of materials is decisive. We believe that the 21st century will end the myth of semiconductor silicon, and mankind will enter the era of inexhaustible organic materials.

9. The difference between digital tube and LCD screen

1. Price difference:

Generally speaking, the price of the digital tube is lower than that of the liquid crystal display module.

2. Display characteristics:

The digital tube is scanned electronically by the electron gun, and the liquid crystal display module is the light through the liquid crystal body for imaging;

The display content of the digital tube is single, while the liquid crystal is relatively rich;

The digital tube is generally a 7-segment 8-character, of course, many have 16-segment middle-meter-shaped, and the liquid crystal can display various contents;

The digital tube is self-luminous, and the liquid crystal is backlit (environment);

The digital tube is the effect of LED light emission, and the liquid crystal is the dark shadow effect caused by molecular deflection.

3. Development trend:

The future LED industry competition will depend on two aspects. One is technology, which includes technology to improve luminous efficiency, reduce cost, and technology to increase device power. There is an extension of existing technology routes in the direction, and new technology routes may also appear; It also includes the process technology to obtain high-quality products, as well as peripherals such as lighting system design and driver chip design technology; the second is scale, on the one hand, because the scale can reduce costs, the market has strong bargaining power; on the other hand, compound epitaxial wafers and integration The silicon chip used in circuit manufacturing is very different in that even the performance of the chip produced on the same epitaxy may have a big difference. This is for applications with high consistency requirements (typically such as LCD panel backlight), a piece of epitaxy Only part of the above meets the requirements, but for large-scale companies, they have a multi-level market structure that can deploy chip products that do not meet the requirements of one market to another market, and the company's overall output efficiency is fully improved.

Under the trend of continuous technological innovation, price decline, and huge potential market, the use of LED displays will become more common, not only in public life and commercial activities, but also in every aspect of our lives. Under this promotion, the LED display industry will gain more development opportunities and maintain a positive trend of vigorous development.

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