Does the linear scheme light have a drive?
1. Linear drive refers to a kind of driver in which the difference between the actual working voltage of LED and the supply voltage of power supply is borne by linear components. The working voltage range is relatively narrow, so it is suitable for the environment where the difference between the actual working voltage and the power supply voltage of LED is relatively small, and it is usually non-isolated. Most of the nonlinear drivers belong to the on-off mode drivers.
2. It is required that the proportion of voltage difference in light channeling should be as large as possible in order to reduce the power loss of high voltage linear IC. The reference lamp switching voltage is between 210 and 270V.
3. The difference between dob and linear scheme is mainly about DoB,Driver on Board or Driverless, which is what we usually call de-power. In fact, it is not no power supply, but a new drive mode which is different from the traditional switching power supply and is a new drive mode derived from LED characteristics.
What are the commonly used led power drive schemes?
The constant current source drive is the best LED driving mode, which is driven by the constant current source without the series current limiting resistor in the output circuit, and the current flowing through the LED is not affected by the change of the external power supply voltage, the ambient temperature and the discreteness of LED parameters, so that the current can be kept constant and give full play to the excellent characteristics of LED.
The driving mode of LED lamp power supply includes two types: the first constant current drive power supply.
Parallel drive: the advantage is that low voltage drive can be used, but more drive channels are needed. Series / parallel drive: when more backlight LED is used, series and parallel combined drive circuits are often used. the structure of this circuit has the advantages of both series and parallel LED drive circuits.
The difference between dob and Linear Scheme
The DOB that appears on the registration website is Day of Birth, which means birthday, which means your date of birth. Is a common word for forms and registrations.
LED DOB scheme is a new LED drive mode, which directly turns AC rectifier into DC, and then controls LED current through IC, so that LED can drive LED lamp beads to emit light with constant current output in a certain range. This scheme can simplify the components and improve the stability and life.
The content of 13CO2 in 12CO2 was measured by 13C mass spectrometer or infrared analyzer, and then the difference between post-test and pre-test was obtained, which was expressed as DOB (deltaoverbaseline).
Dob positive is the abbreviation of Helicobacter pylori positive in carbon 13 breath test, indicating the infection of Helicobacter pylori in vivo.
Connecting three expansion boards, the total output interface can reach 128. the output can be configured to be normally open and close. the standard 485industrial serial port 9600 baud rate is used for communication. the software is compatible with all 485s and TCP/IP controllers. The intelligent elevator controller selects a new generation of access control products designed by the most advanced integrated scheme.
Does EMC Linear Scheme have to pass LED?
1. National laws and regulations, such as CCC requirements. Electromagnetic environment requires that if the LED power supply is only EMI and EMC, it is possible that its own electromagnetic interference will affect the normal operation of other electronic devices in your home. It can improve the anti-interference performance and product quality of the product.
2. Strictly speaking, all electronic devices need EMI testing. Electronic devices with excessive EMI not only work unsteadily, but also affect other electronic devices, and radioactive EMI may even affect the human body. Because the power supply is for other devices, EMI is particularly important in the power supply design.
3. There are no compulsory requirements at home for the time being, if there are certain requirements abroad. For example, to go to Europe, you can do CE, because you are 24V low voltage, you only need to do the EMC test. Mainly depends on where your market is, specific analysis of specific problems.
4. EMC is electromagnetic compatibility, which is defined as “the ability of equipment and system to work normally in its electromagnetic environment and not to cause unbearable electromagnetic disturbance to anything in the environment.” the popular point is to prevent the lamp power supply from interfering with other electrical equipment used in the circuit.
5. If the space is not very small, it is used to be non-isolated, the cost is required to use resistance and capacity, the linear one is well done, the efficiency is 94%, and the constant current is within a certain range.
6. Is the main building LED driver power supply? The voltage over EMC has nothing to do with isolated or non-isolated power supplies. Over-EMC is mainly a problem of filtering and absorbing interference.