When to Choose An AC-DC Power Supply Manufacturer and What Are The Benefits of Choosing An AC-DC Power Supply

AC DC Power Module Filling Requirements
Potting and sealing of AC DC power modules is very important. This process involves not only the protection of AC and DC power modules (waterproof, moisture-proof, dust-proof, anti-corrosion, etc.), but also the thermal design of dules.

Power module potting materials are generally divided into three categories: epoxy resin, polyurethane, and silicone rubber

Due to the hardness of epoxy resin, it cannot be used for stress-sensitive and module packaging and SMT components, so it is basically eliminated in module power supplies. But epoxy resins are also used in cost-critical micropower power supplies due to their low cost. Some domestic bad power supply manufacturers also use this epoxy resin for AC and DC power supply modules, but due to stress problems, the failure rate of this power supply is very high, and buyers are very distressed.

At present, most of the power modules are sealed with molded silicone. For the convenience of operation, the ratio of 1:1 is usually adopted. When designing for AC and DC power modules, attention should be paid to their thermal conductivity. However, the adhesion is not very strong, so a substrate coating can be used to improve sealing.

Fig.1

Polyurethane has been used in China for a period of time, but due to its high hardness, inconvenient maintenance, and the price of silicone rubber, polyurethane is not cost-effective. There is basically no domestic application of it.

Special attention should be paid to thermal conductivity in relation to thermal design. Generally speaking, a thermal conductivity of 0.5w/M·K is defined as high thermal conductivity, and a thermal conductivity greater than 1 is defined as very high thermal conductivity.

Fig.2

The power module is such a highly integrated small and medium-sized switching power supply. In recent years, with the development trend of high and new technology, it has been widely used in industrial electrical, power supply system, instrumentation, urban rail, intelligent security, new energy technology, communication, automation technology and intelligent system industry.

Make sure to type the source type first
The power module can input AC current or AC current. Normally, the FH/DC power module selects AC current input, and the DC/DC power module selects AC input. The high-cubic FH-DC power module can also be used normally under the DC input working voltage standard.

Type in the operating voltage category to select
After confirming the input source, the input working voltage can refer to the manufacturer’s motor selection structure. The communication keys are basically 120V, 230V, 220V. Now FH/DC power modules usually consider 86~265VAC or 150~370VDC types, and 220V also consider 230V types, but the probability of application at 230V will be much worse, and the DC keys are basically 5V~76V.

Fig.3

Select the package type of the item
Product package types include single in-line SIP package, small and medium vertical bare board, dual in-line ultra-small DIP package and rail package. The bare board is composed of a PCB circuit board and various components. It is completely exposed and not very safe, but the cost is low.

DIP packaging is usually strongly recommended. Although it is expensive to lose, it has the characteristics of potting packaging, safety protection, good heat dissipation characteristics of heat pipes, anti-freezing, moisture-proof and stable characteristics. must be selected on a case-by-case basis.

Select the output power of the goods according to the load size
When selecting the output power of the power module, it is usually strongly recommended to reserve the capacity, and the output power of the application is between 30 and 90% of the actual output power. The capacity is large and there are noise problems when working at high frequencies.