What's LED?

29/06/2020

    LED, it's a kind of light source, a solid-state semiconductor devices, called light emitting diode which can convert electric energy into visible light. The two poles mean positive and negative poles, P poles and N poles for short. 

    The heart of LED is a semiconductor chip. One end of the chip is attached to a bracket, the other end is connected with the positive pole of the power supply, so that the whole chip is encapsulated by epoxy resin.

    LED production process:

1. Solidification, conductive/non-conductive glue at the bottom of the bracket (conductivity depends on whether the wafer is up-and-down PN junction or left-and-right PN junction) and then put the wafer into the bracket);

2. Short baking to keep the wafer from moving when glue solidifies the wire;

3. Welding wire, with gold wire to lead wafers and brackets;

4. Pretest, preliminary test whether they can be bright or not;

5. Glue the chips and branches with glue;

6. Bake long and make the glue solidified;

7. Post-test, whether they can be bright or not and whether the electrical parameters are up to standard; 8. Spectrophotometry, roughly differentiated LED chips according to their color and voltage.

    

    According to the packaging states, LED is divided into SMD patch(named by sizes: 2835, 3014, 5050), COB(Chips on Board), light bar (filament).

    LED driving power supply is an electronic component that converts the power supply to a specific voltage and current to drive LED light.

1. Switching Mode Power Supply;

2. Resistance-Capacitance Voltage Reduction;

3. High Voltage Linearity.

   That's all for "what's LED".