Potting (electronics)

File:Small potted pcb transformer.jpg

A small transformer potted in epoxy. The surface visible on the right is formed by the potting compound that has been poured into the plastic box.

In electronics, potting is a process of filling a complete electronic assembly with a solid or gelatinous compound for resistance to shock and vibration, and for exclusion of moisture and corrosive agents. Thermo-setting plastics or silica gels are often used.

Most circuit board assembly houses coat assemblies with a layer of transparent conformal coating rather than potting. Conformal coating gives most of the benefits of potting, and is lighter and easier to inspect, test, and repair.

When potting a circuit board that uses surface-mount technology, it is recommended to use low glass transition temperature (T_g) potting compounds such as polyurethane or silicone, because high T_g potting compounds may break solder bonds as they harden and shrink at low temperatures.

See also

• Integrated circuit packaging
• Resin dispensing

External links

• polyurethane potting at the Open Directory Project
• silicone potting at the Open Directory Project
• epoxy resin potting at the Open Directory Project
• adhesive potting compounds at the Open Directory Project