Four connection methods for LED drive

Nowadays, many LED products use constant current drive to drive LEDs, and LED connection methods are also designed according to actual circuit needs. There are generally four forms of connection: series, parallel, hybrid, and array.

1、 Series connection method

This series connection method has a relatively simple circuit, with the head and tail connected together. The current flowing through the LED during operation is consistent and good. As the LED is a current type device, it can basically ensure that the 

luminous intensity of each LED is consistent. The circuit using this LED connection method is simple and convenient to connect. However, there is also a fatal drawback, which is that when one of the LEDs experiences an open circuit fault, it will cause 

the entire LED string to go out, affecting the reliability of use. This requires ensuring that the quality of each LED is excellent, which will correspondingly improve reliability.

2、 Parallel connection method

The characteristic of parallel connection method is that the LED is connected in parallel at the beginning and end, and each LED is subjected to equal voltage during operation. However, the current may not necessarily be equal, even for LEDs of the 

same model and specification batch, this is due to factors such as production and manufacturing processes. Therefore, the uneven distribution of current in each LED may cause the lifespan of LED with excessive current to decrease compared to ot-

her LEDs, and over time, it is easy to burn out. This parallel connection method has a relatively simple circuit, but its reliability is also not high, especially when there are a large number of LEDs, the probability of failure is higher.

3、 Hybrid mode

Hybrid connection is a combination of series and parallel connections. First, several LEDs are connected in series and then connected in parallel to both ends of the LED driver power supply. Under the condition of basic consistency of LEDs, this con-

nection method ensures that the voltage of all branches is basically equal, and the current flowing through each branch is also basically consistent.

4、 Array mode

The main composition of the array method is: the branch is composed of three LEDs, which are respectively connected to the Ua, Ub, and Uc output terminals of the driver. When all three LEDs in a branch are normal, all three LEDs light up simultan-

eously; Once one or both LEDs fail and open, it can be ensured that at least one LED is functioning properly. In this way, the reliability of each group of LED lighting can be greatly improved, and the overall reliability of the entire LED lighting can also be improved. Adopting this method requires multiple sets of input power supplies in order to improve the reliability of LED operation and reduce the overall circuit failure rate.