The adjustment of parameters such as brightness and color temperature of LED light emitting diode is a key link in LED lighting technology. There are many ways to adjust it. The following will introduce several main adjustment methods in detail.
1. Brightness adjustment
Current control: The brightness can be changed simply by adjusting the current intensity flowing through the LED. High current makes the LED brighter, while lower current reduces the brightness. This method is often used in basic LED circuit design and can be achieved by changing components such as current source, resistor or current driver.
Pulse width modulation (PWM): PWM technology is widely used in LED brightness control. It uses the width and frequency of LED pulse signals to adjust the brightness. By changing the time ratio of high level to low level in each cycle, the effect of different brightness is simulated. Compared with current control, PWM has higher brightness adjustment accuracy and lower power consumption.
Variable resistor control: Variable resistors (such as potentiometers) are commonly used components for adjusting LED brightness. Connect it to the LED circuit, adjust the resistance value by rotating the resistor, thereby changing the current intensity and achieving brightness control. Although the adjustment is intuitive, its adjustment range may be limited to a certain extent.
Constant current source control: Constant current source circuit is one of the common ways to drive LEDs. The brightness is controlled by adjusting the output current of the constant current source. The constant current source can provide a stable current output to ensure the consistency of the LED brightness. This method is suitable for applications that require precise control of LED brightness and have high stability requirements.
2. Color temperature adjustment
The color temperature is mainly adjusted by changing the luminescent material in the LED chip or adding filter materials to change the luminescent color, and by changing the driving current of the LED lamp to adjust the luminescent color. Specifically, the conventional method of LED color temperature adjustment includes using white light LED arrays with high and low color temperatures, and adjusting the overall color temperature adjustment by adjusting the driving current ratio of the two LEDs. In addition, the new method adopts a PWM dimming drive power supply solution, and adds a color temperature adjustment circuit in the back-end circuit of the power supply to achieve color temperature adjustment by adjusting the conduction time ratio of the cold white LED array and the warm white LED array.
In summary, the brightness, color temperature and other parameters of LED light emitting diodes can be adjusted in a variety of ways to meet the needs of different application scenarios.
