There are various control modes for LED display devices to meet different application scenarios and needs. Here are some of the main control modes and their explanations:
1. Current control
Principle: The brightness is adjusted by changing the current flowing through the LED. The brightness of the LED is proportional to its forward current, so adjusting the current can accurately control the luminous intensity of the LED.
Application: Suitable for occasions where fine brightness adjustment is required, such as high-end display screens, stage lighting, etc.
2. Pulse width modulation (PWM) control
Principle: Utilize the visual inertia of the human eye to control the grayscale by periodically changing the width of the light pulse (i.e., duty cycle). PWM dimming achieves the dimming effect by controlling the switching time and duty cycle of the LED lamp. The brightness is adjusted not by changing the power, but by alternating the screen on and off.
Advantages:
* No LED color spectrum shift will be generated because the LED always works between full amplitude current and 0.
* It has extremely high dimming accuracy and is easy to achieve high-precision brightness adjustment.
* There will be no flickering when dimming over a wide range.
Application: It is widely used in LED display screens, LED lighting and other fields, and is an important means to achieve digital control.
3. Centralized control and independent control
Centralized control: It is carried out through a central control panel or mobile phone application, which is convenient for unified management and control, and is suitable for large display screens or occasions that require centralized control.
Independent control: It is realized through independent control devices such as scanning boards and display control devices. Each display unit or area can be controlled independently, which is more flexible and suitable for occasions that require partition control.
4. Wireless control
RF wireless control: It uses RF signals for remote control without wiring, and is suitable for long-distance or difficult wiring occasions.
Wi-Fi wireless control: It connects control devices through Wi-Fi networks to achieve remote control and management, and is suitable for occasions that require network connection.
GPRS wireless control: It uses GPRS networks for data transmission and control, and is suitable for occasions that require remote monitoring and control.
5. Synchronous control and asynchronous control
Synchronous control: It realizes synchronous display of LED display screen and computer monitor, with high real-time performance, and is suitable for occasions that require real-time video and image playback, such as evening parties, concerts, studios, etc.
Asynchronous control: It allows the display screen to be used offline, and it has the ability to store and automatically play programs. It is suitable for outdoor advertising, public welfare propaganda, and other occasions that do not require real-time updates.
6. Specific technology control
3G/4G Internet control: The LED display screen is connected to the Internet through 3G or 4G network, and the control end logs in to the server for remote update and management, realizing fast management without distance limit.
Multi-screen picture synchronization control: Through specific synchronization technology (such as Internet time synchronization, GPS synchronization, etc.), the pictures of multiple LED display screens are displayed synchronously, which is suitable for occasions where advertisements are concentrated.
In summary, there are various control modes for LED display devices, and each mode has its unique advantages and applicable scenarios. In practical applications, it is necessary to select the appropriate control mode according to specific needs.