Generally speaking, the difference between LED power supply and switch mode power supply is that LED power supply is a constant current source, while switch mode power supply is a constant voltage source.

Requirements for LED power supply: 1. Constant current is required; 2. Low temperature, low heat, long lifespan; 3. Small volume; 4. It has the characteristics of being water-resistant, corrosion-resistant, and anti-static; 5. Reduce or isolate high-frequency pollution.

A regular switching power supply is a type of power supply that utilizes modern power electronics technology to control the time ratio of the switching transistor to turn on and off, maintaining a stable output voltage. It is generally composed of a pulse width modulation (PWM) control IC and MOSFET. Ordinary power supplies and low-quality LED power supplies suffer from severe high-frequency pollution, and even with inductors and large capacitors for filtering, the output DC waveform is very complex. Poor power supply, the power supply itself may not be damaged, but the lifespan and light decay of the LED are greatly reduced.

The LED power supply circuit is actually composed of a switch power supply circuit and a feedback circuit. The feedback circuit samples from the load and adjusts the duty cycle or frequency of the switch circuit to control the output of the switch circuit.

Article source: Jiangmen LED Switching Power Supply http://www.gdsaiya.com