Close this search box.

Take you to know the LED power supply

Working principle diagram of LED driver

No matter what, LED lamps and lanterns need an LED power supply to drive them to work; an LED power supply is the heart of LED lamps and lanterns; a quality LED power supply can bring your lamps and lanterns better efficiency and service life. How to distinguish the advantages and disadvantages of LED drive power? Please check the following article written by Kingornan engineers; I believe that you have read the full text and will have a comprehensive understanding of the LED driver.

(If some terms in the article are unclear, please check the “Noun term” table at the end of the article)

Take you to know the LED power supply

what is LED power supply?

LED panel light CE Driver 9 12W

Due to the characteristics of LED lamp beads (only DC drive), between the mains and the LED lamps, an integrated circuit is required to convert the alternating current into direct current (as shown in the diagram below). This integrated circuit is the LED control driver, commonly known as LED driver (LED Driver)

The main role of LED drivers:

  1.  AC to DC
  2. Current size and voltage range required for supplying lamps.
  3.  Provide circuit safety protection for lamps.
  4.  Electromagnetic compatibility processing, filtering processing.
  5. Other intelligent control, etc.

What is DOB?

DOB (also known as Driver-On-Board) is the power supply components and light source together with the aluminum substrate inserted. We can summarize the conventional LED constant current drive program into two kinds; one is a switching power supply, and there is a linear power supply; the principle of these two power supplies can do the DOB program. The DOB program does not affect the product’s quality in saving material costs; the driver components and light source integrated into the aluminum substrate program have been developing rapidly in recent years, and many indoor lighting programs are slowly changing to the DOB direction.

Classification: By Output Type

Constant current power supply: the output current is constant, and the output voltage varies within a certain range with the load resistance (example: DC27-42V 1000mA)
Constant voltage power supply: the output voltage is fixed, and the output current changes with the increase or decrease of the load (example: DC24V 0-1250mA)

Classification: by installation location

Built-in power supply: It is built into the lamp cavity. If the lamp is a metal shell, insulation measures should be taken between the power supply and the lamp cavity.
External power supply: placed outside the lamp, it can be fixed or not depending on the situation, and the shell must be installed for insulation. If it is used outdoors, it needs to be filled with glue and waterproof.

Classification: By Drive Type

Linear drive:

Linear Driver Circuit

Linear drive application is one of the simplest and most direct drive applications. There is no high-frequency switching action, so there is no hidden EMC worry; magnetic components such as transformers can be omitted, and electrolytic capacitors can also be omitted in some applications to achieve high PF and low THD.

Considering power consumption, the main difficulty of IC now lies in how to achieve wider input voltage and achieve high efficiency. In areas where the power grid is relatively stable, single-stage control (100-130/220-240V) has the advantages of low cost and high performance, and has been widely used.

Switch drive:

Switch drive can achieve good current control accuracy and high overall efficiency. The application methods are mainly divided into two categories: buck type and boost type. The step-down switch drive is aimed at applications where the power supply voltage is higher than the terminal voltage of the LED or when multiple LEDs are driven in parallel. The boost switch drive is for applications where the power supply voltage is lower than the terminal voltage of the LED or when multiple LEDs are driven in series.

Classification: by whether or not to isolate

Isolated Power: The conversion process is “Electrical-Magnetic-Electrical”.
Using a transformer, the high voltage is passed through a transformer to drop the voltage to a lower voltage, which is then rectified to a DC output.
Non-isolated power supply: the conversion process is “electrical-electrical”
Use high voltage to reduce the voltage through components such as inductors and then rectify it into DC output.

Non-isolated Driver circuit

Non-isolated Driver circuit

Isolated Driver circuit

isolated Driver circuit

Non-isolated Driver VS Isolated Driver

type input/output efficiency cost volume
Isolated Power isolation transformer isolation normal high big
non-Isolated Power I/O common ground high cost-effective small
type safety reliable Number of components
Isolated Power safer high high
non-Isolated Power risk of electric shock low low

>>If you want to learn more about isolated vs. non-isolated drivers, check out: “Unraveling the Differences: Isolated VS Non-Isolated LED Drivers

Three major wired dimming methods

What do you need to know about wired dimming driver performance?

Price: the lower, the better

This goes without saying;In the case of the same performance and quality, the lower the price, the better.

Compatibility: The higher, the better

This indicator refers to the adaptability between different manufacturers of power supply drivers and dimmers/control systems. For example, in silicon control, many manufacturers do silicon power supply drivers that are not compatible with most silicon dimmers on the market; because there are more types of silicon dimmers, there is no fixed standard, resulting in each family to do the dimmers are different, so the power supply with the compatible effect is difficult to meet all compatible.

On the contrary, DALI control, DALI has a standard communication protocol, and there is a special DiiA Association control, so as long as the DALI standard protocol meets the power supply and control system is no compatibility problem.

Communication mode: two-way better than one-way

Unidirectional: is only by the dimmer / control system to the driver control commands; the driver can only passively receive the execution of the command but can not receive feedback signals.
Bidirectional: means that the dimmer / control system to the driver control commands, the driver receives the execution of the command will also provide feedback to the system and can see the driver’s execution status.
(The benefits of two-way communication: you can monitor the operational status of the driver in the system in real-time, whether the driver is offline, and whether it is working properly.)

Control line: single light control can achieve more settings

Loop: The control needs to form a loop through the wire before the Dimming driver can achieve control.
Loop + single lamp: the control needs to form a loop through the wire after the Dimming driver can control the loop separately in the circuit of a lamp device. It can be a one-to-one command and can also be one-to-many command. (send a signal similar to the teacher called out alone to talk, only the person or persons called to the command will be executed)

Signal cable: the simpler the wiring, the better

Do not need better than the need, non-polarity is better than polarity, dimming control wiring, the simpler, the less likely to be wrong, the lower the learning cost.
Non-polarity: refers to the connection without distinguishing the polarity of the signal line positive and negative access.
Input firewire: refers to the control method controlled by the voltage signal on the input firewire.

Debugging: The simpler, the better

The simpler the lighting scene setting after the installation of the luminaire and control line is completed, the lower the learning and application costs.

SCR VS 0/1-10V VS DALI, how to choose the three major wired dimmers?

suitable for project renovation (complete lighting scenes have been installed), because thyristor dimming does not require re-adjustment of the lighting wiring, for projects that do not want to make major renovations and do not have high requirements for dimming effects Very friendly.

0/1-10V dimming:

: suitable for projects that have certain requirements for dimming effects, but the cost is relatively tight. Although there is no single lamp control function, its overall dimming effect is better than thyristor dimming, and the cost is moderate.

suitable for building control, it has the stability of wired dimming, and also has the dimming diversity brought by single lamp control.

SCR VS 0/1-10V VS DALI Performance Comparison

cost compatibility communication mode control wiring
SCR low low unidirectional loop
0/1-10V moderation moderation unidirectional loop
DALI high high two-way loop
SCR signal signal cable debugging application characteristic
0/1-10V simulation input livewire unnecessary better price
DALI simulation required, polarized simple better effect
digital required, non-polar complex smart centralized control

Three major wireless dimming methods

Zigbee - low rate, low power, low cost, large field use.

ZigBee is an internationally accepted two-way wireless communication technology. Each of its network ports can theoretically connect to more than 65,000 ports. It is mainly used for short-distance, low-power and low-speed transmission between various electronic devices Data transmission, which can be embedded in various devices, is used in many fields such as home furnishing, industry, agriculture, education, and medical care. It is the most mature wireless technology currently used, represented by Amazon Echo, which occupies the main foreign wireless technology market.

Bluetooth - low cost, direct cell phone connection, small indoor space use.

Bluetooth has a variety of connection methods: point-to-point, broadcast and mesh networking. Bluetooth mesh, represented by the Tmall Genie Ecological Chain, integrates Bluetooth functions in a large number of consumer electronic products, especially mobile phones, allowing Bluetooth to provide a wider range of interoperability among multiple brands. For example, each smart home hardware in the Bluetooth mesh network can be connected to each other and send commands for control and linkage. It is the wireless technology that is closest to the characteristics of the Internet of Things.
At present, Bluetooth dimming products are mainly in the field of smart home, and they also have good application effects in indoor commercial lighting in small spaces.

Wifi - fast and efficient transmission, large data transmission single product device use.

Now Wi-Fi is basically an essential device for every household. It can access wireless signals at any time, has strong mobility, fast data transmission speed, and high efficiency, allowing users to have a very good experience, but the corresponding shortcomings are also very obvious—— Problems such as high power consumption, small number of accessible nodes, and poor confidentiality and security limit the application of Wifi technology in large fields, generally requiring large data transmission and pluggable use (eliminating the problem of Wifi power consumption). ) is used in a small number of smart devices, and is less used in lighting dimming control.At present, Bluetooth dimming products are mainly in the field of smart home, and they also have good application effects in indoor commercial lighting in small spaces.

Zigbee VS Bluetooth VS Wifi

wifi zigbee BLE mesh
frequency 2.4GHz/5GHz
power consumption 10-50mA 5mA 20mA
low power mode nonsupport support support
range 100-300m 10-100m 2-30m
safety low moderation high
distribution mode Wifi router Relayable distribution network Directly connected to network distributor
transfer speed 300Mbps 250Kbps 1Mbps
  • Zigbee currently has a very mature system and application areas, is the most suitable for low-speed transmission inside the wireless, and the need to connect a large number of control nodes of large industrial, agricultural, educational, the home master networks.
  • Bluetooth, in three ways in the performance cost compromise, is along the Zigbee early development path gradually expand share, the current advantages of its cell phone direct connection in small space home, commercial, office and other indoor lighting has a greater advantage.
  • Wifi coverage and transmission rate are extensive; it is recommended to use in need for real-time large data transmission to improve the use of experience of a small number of single product smart devices.

Noun term

NO Name Symbol Description
1 input voltage input AC85-265V (Isolation Wide Voltage) AC100-265V (Non-Isolation Wide Voltage) AC180-265V (Central European Narrow Voltage) Linear Selection (100-130V/220-240V)
2 output voltage output For example: DC24-42V 300mA±5%; DC48V 2.1A
3 frequency hz The frequency of alternating current in the power system of different countries is different, generally 50 or 60 Hz. In Asia, countries and regions such as China, Japan, Thailand, India and Singapore use 50Hz, while South Korea, the Philippines and Taiwan use 60Hz, most European countries use 50Hz, and the countries in the Americas that use 60Hz are mainly Mexico, the United States, and Canada.
4 power p Power calculation formula: P=UI
5 power factor pf The general definition of power factor is the ratio of active power to apparent power. A low power factor indicates that the reactive power of the circuit is large, and the heavier the load of the power supply equipment, the more unstable the power grid. For example, if there is a 9W bulb lamp, the output voltage of the power supply is 30V and the current is 300mA. After the whole lamp is installed, it is displayed on the electrical parameter analyzer, the voltage is 220V, the current is 70mA, and the power is 15.4W. 0.5 0.9
6 transfer efficiency / It is to measure the AC active power of the input power supply, how much is converted into DC power (with heat loss, etc.), depending on the circuit technology of the switching power supply of the power supply. Under the same power, the higher the power replacement efficiency is, the higher the light efficiency is.
7 strobe / Ripple current is the AC component that still exists after rectification and filtering superimposed on DC, and has different frequencies and curves. Causes the power of the LED module to fluctuate, which in turn causes the brightness to vary. Flicker-free refers to filtering out the AC components in the power supply output through related circuits such as filter circuits, bipolar power supply schemes, de-ripple circuits, and valley-filling circuits. Energy Star puts forward requirements on the light output frequency of the lamp, and the light output frequency of the LED lamp should be ≥120H. Low P low frequency flicker, high P low/high frequency flicker.
8 surge / An instantaneous overvoltage that exceeds the normal operating voltage. A surge is a violent pulse that occurs in only a few millionths of a second and can be caused by: heavy equipment, short /circuits, power switching, or large engines. A surge protection circuit composed of a varistor and TVS can effectively absorb the sudden huge energy to protect the connected equipment from damage. 0.5KV 1KV 2KV 6KV
9 EMC / Electromagnetic compatibility: On the one hand, it means that the electromagnetic interference generated by the LED lamp to the environment during normal operation cannot exceed a certain limit (EMI); on the other hand, it means that the LED appliance has a certain degree of electromagnetic interference in the environment. immunity, known as electromagnetic susceptibility (EMS)

Luminaire anti-electrical shock rating

Electrolytic capacitor The main performance of LED light Application specification
class 0 Protection relies on basic insulation; insulation between accessible parts and enclosures and live parts. It is suitable for occasions with a high degree of safety, and the lamps are easy to install and maintain, such as lamps under the conditions of dry air, less dust, and wooden floor lamps.
class 1 In addition to the basic insulation, the easily accessible parts and the shell are provided with grounding devices, and once the basic insulation fails, there will be no danger. Used for lamps with metal shells, such as spotlights, street lights, garden lights, etc.
class 2 In addition to basic insulation, there is supplementary insulation, which can be made into double insulation or reinforced insulation to improve safety. Good insulation, high safety, suitable for lamps with poor environment and people often touch, such as table lamps, portable lamps, etc.
class 3 Use safety extra-low voltage (generally 42V is used for hand-held electric tools; 36V, 24V, 12V are used for safety lighting in general places) The IEC standard stipulates that under normal conditions, the upper limit of the contact voltage is 50 volts for AC or 120 volts for DC without ripple. In special cases, the upper limit of contact voltage is 25 volts AC or 50 volts DC without ripple.


Kingornan has been a factory in the commercial lighting industry for 10+ years; we have a wide range of product lines and customer service experience. If you have any product needs or questions, please get in touch with our team.

>>For more information about LED strip lights, check out our other LED strip lights blogs.

>Check out the latest styles, the hottest LED strip lights.

>>For more information about LED Magnetic Lights, check out our other LED Magnetic Lights blogs.

>>Check out the latest styles, the hottest LED Magnetic Lights


News Category

Get more information

Please leave your message if you have any questions about the products