There are many types of LED power supplies, and the quality and price of each type of power supply vary greatly. This is also one of the important factors affecting product quality and price. LED driving power supplies can usually be divided into three categories: one is a switching constant current source, the other is a linear IC power supply, and the third is a resistor-capacitor step-down power supply.

Switch constant current source:

A transformer is used to convert high voltage into low voltage and perform rectification and filtering to output stable low-voltage direct current. Switching constant current sources are divided into isolated power supplies and non-isolated power supplies. Isolation refers to the isolation of output high and low voltages. It is very safe, so the insulation requirements of the shell are not high. Non-isolation is slightly less safe, but the cost is also relatively low. Traditional energy-saving lamps use non-isolation power supplies and are protected by insulating plastic shells.

  The switching power supply has relatively high safety (generally low output voltage) and stable performance. The disadvantage is that the circuit is complex and the price is high. Switching power supply technology is mature and its performance is stable. It is currently the mainstream power supply for LED lighting.

Linear IC source:

One IC or multiple ICs are used to distribute the voltage. There are few types of electronic components, the power factor and power efficiency are very high, no electrolytic capacitors are needed, the life is long, and the cost is low. The disadvantage is that the output high voltage is not isolated and has strobe, so the outer shell is required to be protected against electric shock isolation.

Those on the market that claim to have no (removed) electrolytic capacitors and long lifespan all use linear IC power supplies. IC driver power supply has the advantages of high reliability, high efficiency and low cost, and is the ideal LED driver power supply in the future.

Resistor-capacitor step-down power supply:

A capacitor is used to provide driving current through its charge and discharge. The circuit is simple and the cost is low, but the performance is poor and the stability is poor. It is easy to burn out the LED when the grid voltage fluctuates. At the same time, the output high voltage is non-isolated and requires an insulating protective shell. The power factor is low and the life is short. It is generally only suitable for economical low-power products (within 5W).

When it comes to power supply, LED driver is also a type of switching power supply, but it has several special characteristics, which are also common to this type of switching power supply. 

These particularities are:

A: Its voltage output is a multiple of 3.2, which means the voltage output is in the form of 3.2V, 6.4V, 9.6V, 12.8V, but the maximum is generally no more than 25.6V. Because after this number is exceeded, when the LED is turned on, there is a possibility that the last LED that was turned on will be burned out instantly due to poor consistency of the product. Moreover, this voltage is not constant, but changes with the load to achieve the purpose of constant current.

B: Its output current is constant. The ideal circuit is that no matter how the LED characteristic curve changes, the current of the driving power supply remains unchanged. However, due to component accuracy, there will still be a small amount of change, and this change is also an important parameter to judge whether the drive circuit is excellent.

C: Its circuit requirements are the simplest, because many times, the circuit is required to be installed in a small space to match the convenience of LED lighting, so the circuit should be as simple as possible, which can also save costs and reduce energy consumption.

Mondial is a professional lighting company that has been established for more than ten years and has a very professional sales and technical team.If you have more questions about LED drivers that you would like to discuss, please contact us. Looking forward to communicating with you.

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