Kazakhstan acdc power module potting requirements(2)

Epoxies cannot be used for stress-sensitive and module sealing due to their hardness and are basically eliminated by module power supplies. However, due to its low cost, this epoxy is still used in cost-sensitive micropower supplies. Some domestic bad Marine boost/buck voltage power supply manufacturers also use this epoxy resin acdc Marine boost/buck voltage power supply module. However, due to stress problems, the failure rate of this Marine boost/buck voltage power supply is very high, and buyers are miserable.

input protection circuit
General module power products have built-in filters, which can meet the requirements of general power supply applications. If a more demanding power system is required, an input filter network should be added. An LC or π-type network can be used, but care should be taken to choose a smaller inductance and larger capacitance as much as possible.
In order to prevent the transient high voltage of the input power supply from damaging the power supply of the module, it is recommended that the user connect a transient absorption diode at the input end and use it with a fuse to ensure that the module is within a safe input voltage range. In order to reduce common-mode noise, Y (Cy) capacitors can be added, and a few nf high-frequency capacitors are generally selected. R is a fuse, D1 is a protection diode, and D2 is a transient absorption diode (P6KE series).

At present, the most commonly used power module is the addition of silicone. This kind of silica gel is generally 1:1, which is easy to operate. When acdc potting power modules, attention should be paid to its thermal conductivity. However, the bonding ability is not very strong, and it can be improved with primer.

Polyurethane has been used in China for a period of time, but due to its high hardness, inconvenient maintenance, and the price reduction of silicone rubber, the cost performance of polyurethane is not high.