LED is a semiconductor device with sensitive characteristics and negative temperature characteristics. Therefore, in the application process, it needs to work stably and protect it, which gives rise to the concept of driving. The requirements of driving power supply for LED devices are almost harsh. Unlike ordinary incandescent bulbs, LED can directly connect 220V AC power.
Constant current drive of LED
LED is driven by low voltage of 2-3 volts. It is necessary to design complex conversion circuit, LED lamps for different purposes, and different power adapters.
In the international market, foreign customers have very high requirements for efficiency conversion, effective power, constant current accuracy, power life and EMC of LED driver power supply. To design a good power supply, these factors must be considered comprehensively, because power supply plays an important role in the whole lamp as human heart.
When using LED as display or other lighting equipment or backlight, it needs constant current drive. The main reasons are:
1. Avoid driving current exceeding the maximum rating and affect its reliability.
2. Achieve the expected brightness requirements and ensure the consistency of brightness and chroma of each LED.