Due to the inherent shortage of CCFL backlight technology and products on traditional LCD display devices, people have been looking for alternative technologies and products. In the process, LED backlight technology products have been included in the selection of people. The following five LED circuit designs are presented for readers to appreciate.
LED backlight
Due to the inherent shortage of CCFL (Cold Cathode Fluorescent Lamps) backlight technology and products on traditional LCD display devices, such as narrow color gamut, low energy efficiency, high power consumption and short life, people are always looking for With its alternative technology and products, LED backlight technology products have been included in the selection process.
Application field
LED is the backlight of LCD TV, the main purpose is to improve the picture quality, especially in color saturation, the LED backlight technology display can obtain a wide enough color gamut to make up for the lack of display color of the liquid crystal display device, so that It can meet or exceed the requirements of Adobe RGB and NTSC color standards, and can reach NTSC raTIo more than 100%. Among them, Sony introduces LCD TV panel with LED backlight, especially emphasizing the performance of bright red and dark green, which can display more realistic than the past. s color. At the same time, because of the planar light source characteristics of the LED, the LED backlight can also realize the color and chromaticity adjustment function of the sub-region that the CCFL cannot match, thereby realizing more accurate color reproduction to meet the needs of the graphic publishing and graphic design work. The dynamic adjustment allows the brightness and contrast to be dynamically corrected when displaying different images for better picture quality.
Here are five LED circuit designs for readers to appreciate:
Driver for 60 white LEDs
For example, the LT3598 is used to drive six channels of 60 LEDs, and the current of each string of LEDs is set to 20mA. The CTRL pin and the PWM pin are responsible for providing simulated dimming and digital dimming, respectively.
Driver for 36 white LEDs
The LT3598 is used to drive four channels of 36 LEDs, and the current per LED is set to 25mA. The LT3598 is designed to drive up to 6 strings of LEDs with an output voltage of up to 44V.
Driver for 20 white LEDs
The LT3598 is used to drive 4 channels of 20 LEDs, and the current per LED is set to 20mA. The LED dimming function is implemented using an analog dimming circuit on the CTRL pin and a pulse width modulation dimming circuit on the PWM pin.
Car battery powered driver for 20 LEDs
The LT3598 is used to drive 2 channels of 20 LEDs, and the current per LED is set to 90mA. The LT3598 accurately regulates LED current even when the input voltage is higher than the LED output voltage.
LED driver for 30 white LEDs
The LT3598 is used to drive 3 channels of 30 LEDs, and the current per LED is set to 60mA. The switching frequency can be set with an external resistor from 200kHz to 2.5MHz.
The LT3598 is a versatile LED driver with a built-in power switch that is suitable for driving multiple strings of LEDs. With its rugged fault detection, it even provides a high PWM dimming ratio. In addition, a voltage loop regulates the output voltage when all LED strings are open. In addition, the advantage of LED as a backlight is that it can replace the use of color filter. The three-color RGB LED uses color sequenTIal technology to achieve the full color effect by utilizing the characteristics of human vision persistence, so it can replace the color filter. Of course, this must be achieved in conjunction with the reaction speed of the liquid crystal. However, to reach this realm, there are still many difficulties that must be overcome. The remarkable features of LED are high photoelectric conversion rate, high color saturation, small size, vibration resistance, no toxic substances, low voltage power supply, safety to human body and long life.
Electronic cigarettesÂ
Shenzhen Aierbaita Technology Co., Ltd. , https://www.aierbaitavape.com