microcontrollercovering

Microcontroller covering is a set of techniques used to apply protective coverings to microcontroller units (MCUs) or MCUs on printed circuit boards. The term covers conformal coatings, potting, and overmolding used to shield the device from moisture, dust, chemicals, vibration, and electromagnetic interference. It is common in harsh environments, such as automotive, industrial, and outdoor electronics.

Conformal coatings are thin protective layers applied over assembled boards. Types include acrylic, silicone, polyurethane, and epoxy. They provide moisture and chemical resistance and help with insulation. Coatings are typically applied via brushing, spraying, or dipping and cured under specified conditions.

Potting and encapsulation involve pouring or injecting material to completely encase the MCU and nearby components in epoxy or silicone elastomer. This yields robust environmental protection and EMI shielding, at the cost of added thickness and difficulty of repair.

Overmolding deposits a molded polymer around a subassembly, combining protection with mechanical strength and sometimes EMI shielding.

Design considerations include thermal management, reworkability, inspection, adhesion, material compatibility, and regulatory compliance. The choice depends on environment, required IP rating, cost, and PCB layout.

Standards and testing: conformal coatings must meet IPC-CC-830A; environmental tests may include humidity, thermal cycling, and chemical exposure. IP ratings may apply to potted assemblies; reworkability varies.

See also: conformal coating, encapsulation, potting, overmolding, electronic packaging.