Power adapter features

　　The power adapter has high efficiency, the circuit has complete protection measures (covering overcurrent, overvoltage, and overtemperature), and the power supply has built-in short-circuit protection. When the load is short-circuited or the load is too heavy, the product will automatically protect it. It is a super reliable power supply.

　　Light weight, easy to carry, replace the traditional transformer. Power products are divided into two categories of products for indoor use and outdoor use. Products for outdoor use are sealed and potted, waterproof and moisture-proof, suitable for various environments; easy to install, can be hung or placed flat on a supporting object; for indoor use The product structure has no waterproof function and is only suitable for indoor installation.

　　The traditional energy-consuming linear regulated power adapter actually uses energy-consuming components connected in series or in parallel in the load circuit to change its energy consumption to stabilize the voltage of the load. When the load voltage increases, the equivalent resistance of the energy-consuming circuit increases, so that the voltage on the load decreases; on the contrary, when the load voltage decreases, the energy consumption of the resistance is reduced and the load voltage is increased. Because in the regulated range, the energy-consuming circuit works in the linear region, and its voltage drop within this range is proportional to the increase in the input voltage and inversely proportional to the increase or decrease of the load current, so it is also called a linear regulated power adapter , Or relative to the current digital circuit, it can also be called an analog stabilized power adapter;

　　Both switching power supplies and adapters are switching power supplies, which are composed of high-frequency switching tubes and their control circuits. The adapter power supply is a regulated switching power supply, and the switching power supply charger has a floating charge function. The voltage becomes larger as the current decreases, and then there is only voltage but no current.

　　The energy consumption of the energy-consuming regulated power adapter is necessary and inevitable, because its voltage stabilization process is realized by the amount of energy consumption. Because of this, the wider the voltage regulation range of this kind of regulator, the more the input/output voltage can be regulated. The greater the difference, the greater the energy consumption, which is obvious. After 220V city power is rectified, it outputs 300V direct current. It is impossible to output stable 5V, 12V low-voltage direct current through this type of regulator. The energy-consuming low-voltage output voltage stabilizer must be used in conjunction with the power frequency transformer, which causes the volume and weight of the voltage stabilizer to increase, as well as additional losses (copper loss and iron loss of the transformer).

　　The efficiency of filtering is greatly improved, and the capacity and volume of the filtering capacitor are greatly reduced. The operating frequency of the switching power supply adapter is basically above 50kHz at present, which is more than 1000 times that of the linear stabilized power adapter, which makes the filtering efficiency after rectification almost 1000 times higher; even if half-wave rectification is used and capacitor filtering is added, The efficiency has also increased by 500 times. Under the same ripple output voltage, when the switching power supply is used, the capacity of the filter capacitor is only 1/500～1/1000 of the filter capacitor in the linear stabilized power supply.

　　The emergence of switching regulators has completely changed the concept of voltage regulators. As the name implies, the switching regulator turns continuous direct current into pulses of intermittent power supply through switching action, and then through energy storage filter elements, the discontinuous pulses become continuous direct current. The switching regulator uses the output stage to repeatedly switch the "on" and "off" states, and together with the energy storage components (capacitors and inductors) to produce an output voltage. Its adjustment is realized by adjusting the switching timing according to the feedback sample of the output voltage. The output voltage can be changed by controlling the on/off time ratio, and then the on/off action time can be controlled by the change of the output voltage to stabilize the output voltage. Obviously, if the on/off has ideal characteristics in this process, there should be no loss, and the switching time ratio can vary widely. Therefore, it is also possible for a switching regulator to directly stabilize a 300V direct current output to 5V, eliminating the need for a power frequency transformer, which is one of the greatest advantages of the power adapter. The highest efficiency of the current power adapter has reached 95%, and the power-to-volume ratio has reached 3.2W/cms. Compared with the energy-consuming regulator with the same output power, the consumption of non-ferrous metal materials has been reduced by more than 90%. At present, there are many types of power adapters, and the performance gap is huge, but each has its own advantages and special fields, so it is difficult to compare with energy-consuming regulators in specific data. This book will introduce its characteristics and application fields in each special purpose power adapter. 1, 2 power adapters have problems and current solutions

Read recommendations:

Transformer，High Frequency Transformer，Frequency Transformer

EI-28 AC ADAPTER LINEAR ADAPTOR Linear Power Adapter Switching Power Adapter Linear Adapter

12V2ASwitching Power Supply

Maintenance steps and methods of power adapter

Switching power adapter circuit technology introduction