Issue link: https://iconnect007.uberflip.com/i/1544707
protected with RF-compatible polyurethane potting while maintaining reliable wireless performance. GPS location data, cellular connectivity, and short-range communications can be transmitted from within sealed, ruggedized housings without degradation, even under prolonged exposure to vibration, moisture, and temperature extremes. This combination of RF integrity and environmental durability is essential to the long-term reliability of telematics-enabled trucking systems. Lessons Learned Relevant to Trucking The lessons learned in automotive and industrial electronics translate directly into trucking applica- tions. For example, in tire pressure monitoring systems (TPMS),each sensor integrates a MEMS pressure transducer, an ASIC, a battery, and an RF trans- mitter inside a compact package mounted at the wheel. These modules endure constant rotation, centrifugal force, heat from braking, and chemical exposure from road debris. Polyurethane potting compounds have become standard, protecting electronics while allowing the RF transmitter to communicate with the truck's central system. The performance requirements mirror those of other wireless truck sensors, making TPMS a model for successful encapsulation. ADAS camera and radar modules mounted externally on tractors are equally dependent on circuit board protection. Exposure to rain, road salts, high-pressure washes, and wide thermal cy- cling can quickly degrade unprotected electronics. Silicone gels can provide temporary relief but may allow water vapor penetration over time. Polyure- thane encapsulants, tailored for RF transparency, create a more durable solution. They provide me- chanical stability against vibration while ensuring that radar or lidar signals are not degraded (as shown in Figure 2, page 48). Telematics hubs, which manage Wi-Fi, Bluetooth, and V2X communication between the truck and external infrastructure, represent a third critical application. These modules are frequently housed in areas exposed to condensation and tempera- ture cycling. Potting and conformal coating with RF-friendly polyurethane compounds enable these 50 SMT007 MAGAZINE I MAY 2026 hubs to maintain continuous connectivity without bulky metal housings or elaborate sealing gaskets. In an industry where space, weight, and durability are at a premium, this approach offers significant advantages. Beyond performance, these examples highlight broader industry trends. The move toward au- tonomy demands sensors that function flawlessly in every scenario, making robust circuit board protection strategies essential for safety. Fleet operators are also under pressure to meet sustain- ability targets, driving interest in encapsulants that can be disassembled or recycled at end of life. At the same time, supply chain resilience has become a business imperative. Circuit board protection solutions that extend sensor lifespans and reduce replacement rates lower the risks of downtime, maintenance delays, and parts shortages. Processing Considerations The success of any potting strategy depends not only on material chemistry, but also on process- ing precision. Two-part systems require accurate ratio control and thorough mixing to achieve full cure and expected properties. Incomplete mixing can leave unreacted components that compromise adhesion or moisture resistance. Void-free encapsulation is equally critical. Trapped air bubbles create weak points that allow moisture ingress or concentrate mechanical stresses. Techniques such as vacuum mixing, slow Figure 3: Controlled dispensing of potting material onto a PCB ensures complete coverage while minimizing air entrapment and defects.