What are the classifications of LED power supplies?

1. Driver power supply manufacturers introduce that LED power supplies can be divided into two categories according to the driving form: A. Voltage regulator tube type: 1. After the voltage regulator power supply circuit determines the various main parameters, the output refers to a fixed working voltage, but the output current changes with the adjustment of the load. 2. Although the voltage-stabilized power supply circuit is not afraid of load lead-in, load short-circuit failure is prohibited

3. The voltage fluctuation after the rectifier will affect the chromaticity of the LED

4. To make each string of LEDs display uniform brightness by driving them with a regulated power supply circuit, appropriate resistors must be added. B. Constant current type: 1. Constant current optocoupler circuit to drive LEDs is very ideal, but the disadvantage is that the cost is relatively high. 2. Although the constant current power supply circuit is not afraid of load short-circuit failure, it is forbidden to lead the load. 3. The output current of the constant current optocoupler circuit is relatively stable, while the output AC voltage changes within a certain range with the different values of the load resistance. 4. To limit the number of LED applications, because it has a larger current and voltage value

2. Driver power supply manufacturers introduce that LED power supplies can be divided into six categories according to the circuit structure:

1. Basic transformer step-down: Driver power supply manufacturers say that the advantage of this type of power supply is its small size, but its disadvantages are its heavy weight and low power efficiency, which is generally between 45% and 60%. Due to its low stability, it is rarely used. 2. Capacitor voltage reduction: This method of LED power supply is easily affected by grid voltage fluctuations, the power supply efficiency is not high, and it is not suitable for LED flashing. Because the power supply circuit relies on capacitor voltage reduction, during flashing use, due to the effect of charging and discharging, the instantaneous current through the LED is huge, which can easily damage the processing chip. 3. Electronic transformer voltage reduction: The shortcomings of this type of power supply structure are low conversion efficiency, narrow voltage range, generally 180~240V, and great influence of ripples. 4. Resistor voltage reduction: This type of power supply mode has low power efficiency and low overall reliability. Since the power supply circuit is based on resistor voltage reduction, it is too affected by the voltage fluctuation of the power grid, and it is not easy to make a voltage regulator power supply. In addition, the voltage reduction resistor itself consumes a large part of the energy. 5. RCC step-down power supply switching power supply: This method of LED power supply is characterized by a wide range of voltage regulators and very high power efficiency, which can generally range from 70% to 80%, and is widely used. The disadvantages are usually that the switching frequency is difficult to control, the load working voltage ripple index is relatively large, and the ability to adapt to abnormal loads is poor. 6. PWM controlled switching power supply: At present, the LED power supply customized by PWM control method is still ideal, because the output voltage or current of such switching power supply is so stable. The power conversion efficiency is very high, generally reaching 80%~90%, and the output voltage and current are very stable. This type of LED power supply mainly consists of four parts: input rectifier and filter part, output rectifier and filter part, PWM voltage regulator control part, and power switch heat transfer part. And this type of power supply circuit has complete protection measures and belongs to a very reliable power supply.