Light emitting diode is a kind of commonly used light emitting device, which emits energy through the combination of electrons and holes. It is widely used in the lighting field. LED can efficiently convert electric energy into light energy, which is widely used in modern society, such as lighting, flat panel display, medical equipment, etc. What is the voltage drop of LED? Let's take a look.

When designing the LED drive circuit, the common fault is based on the typical value k.yp of the LED positive guide voltage drop. This design idea connects multiple LEDs in series and in parallel, and assumes that the total positive conduction voltage drop of each LED string is the same, and the current flowing through each string is also the same. In practice, the error of LED positive guide voltage drop is very large.

1. Calculation method of LED voltage drop.

There are many methods to calculate the voltage drop, and the method to calculate the voltage drop of LED is the same. What are the methods for calculating the voltage drop of LED? First, the load current is estimated, and the current is calculated according to the power of the equipment. The current is related to the power and also has a direct relationship with the voltage. The current is calculated directly using the power;

Then it is the calculation of voltage. According to the load distance of LED, the loss value of voltage is estimated, and the section area is selected according to the current. Then the LED voltage drop can be calculated.

2. Calculation formula of LED voltage drop.

With the method of calculating the voltage drop of LED, of course, the formula is also applied. The current I calculated first is I=P/1.732 × U × cos θ， Where P power, U voltage, cos θ Power factor;

Then comes the calculation formula of resistance R= ρ× L/S, ρ It refers to the conductor resistivity, L is the length of the line, and S is the cross-sectional area of the line; This is the formula for calculating the voltage drop of LED, Δ U=I × R. The voltage multiplied by the resistance gives the difference in the voltage drop of the LED. It is so simple, it is so fast.