Among various connection forms of LED beads, it should be understood that the configuration of LED beads in applications depends on various factors such as application requirements, LED parameters and quantity, input voltage, efficiency, heat dissipation management, size and layout limitations, and optics. The simplest configuration form is a single LED, which has many application examples, such as headlights, map lights, reading lights, etc. in cars.

Although the current power and brightness of LED beads are not very high, in practical use, flat lighting is usually required. Therefore, multiple LED beads need to be combined side by side according to needs to meet application requirements such as large range, high brightness, dynamic display, color conversion, and matching requirements between LED and setting driver.

1. Overall series connection form: 1. Simple series connection form: LED 1? Connect the head of LED n, and the current flowing when the LED beads act is equal. For LEDs of the same specification and batch, there may be slight differences in the voltage of individual LEDs. However, LED beads are current type devices, which can ensure consistent luminous intensity. However, in contrast, simple series connected LEDs have the characteristics of simple circuits and convenient connections. However, due to the use of series connection, when any LED encounters an open circuit fault, the overall LED light column will turn off, affecting the reliability of use.

2 parallel double tube series connection form: an improved series connection form in which each LED is connected in parallel. In this connection method, the breakdown voltage of each burner diode is higher than the action voltage of the LED bead. When the LED bead is working normally, filter the diode VD

Due to the inability of Vdn to conduct, the main reason is that LED n is powered on, and the LED bead column is damaged. When the LED column is open, VD1? The Vdn is conducting, and the other LEDs of the faulty LED bead are electrically circulating and emitting light. Compared with the simple series connection shown in Figure 1, this connection method significantly improves reliability.

2. Overall parallel form: 1. Simple parallel form: The LED 1LEDn heads in simple parallel form are connected in parallel, and each LED bead bears the same voltage during operation. From the characteristics of LEDs, it can be seen that they belong to current type devices, and small changes in voltage applied to LED beads can cause significant changes in current.

In addition, due to limitations in LED manufacturing technology, even for the same batch of LED beads, there are inherent differences in their performance. Therefore, LED 1 can be used at a time of 63? When the LED n operates, the current flow of the LED bead is not equal.

From this, it can be seen that the uneven distribution of current in each LED bead may lead to a sharp reduction in the lifespan and burnout of LED with excessive current. This connection method is very simple. However, the reliability is not high, especially in applications with a large number of LEDs, which can easily lead to usage failures. For the reliability issue in the parallel form of independent matching in Figure 3, the parallel form of independent matching is a good method.

Each LED in this method has its own variability in current (driving V+output terminals of L1~Ln, respectively), ensuring that the current flowing through each LED is within the required range, with good driving effect, complete protection for a single LED, and no impact on the action of other LEDs in case of a fault. It can match LED features with significant differences.