Today we will introduce the specific differences between constant current power supply and constant voltage power supply and the principle of constant current power supply. Constant current power supply and constant voltage power supply play an important role in people's production and life, so many people are familiar with these two terms. Although constant current power supply is not as widely used as constant voltage power supply, it still plays a very important role in people's lives.
A constant current power supply is a power supply that keeps the output current constant, while a constant voltage power supply keeps the output voltage constant. The two have different advantages and disadvantages in applications. A constant current power supply can adjust the output voltage according to the required load, but the output voltage is not necessarily constant; on the contrary, a constant voltage power supply can adjust the output current according to the required load, but the output current is not necessarily constant. Therefore, in situations where stable output current and low flexibility are required, a constant current power supply is more suitable than a constant voltage power supply; in situations where stable output voltage and high flexibility are required, a constant voltage power supply is more suitable.
Why do LED lights use constant current instead of constant voltage?
In the driving circuit of LED lamps, using a constant current power supply can stabilize the brightness of the LED lamp, because the brightness of the LED is proportional to the current. If a constant voltage power supply is used, it will cause current fluctuations when the load changes, which will affect the brightness of the LED. In addition, since the relationship between the resistance and voltage of the LED is not linear, a slight deviation in the use of a constant voltage power supply may cause a drastic change in current, thereby burning out the LED lamp. Therefore, in the LED driving circuit, using a constant current power supply can better protect the LED.