Connectors on the Move

CONNECTORS AND LEADFRAMES CONNECT ELECTRONIC COMPONENTS AND SENSORS IN CARS THIERRY MICHAUT, AUTOMOTIVE PRODUCTS ENGINEERING MANAGER , AXON’ CABLE ROLAND MARKÓ-MARTON, DESIGN ENGINEER , AXON’ KÁBELGYÁRTÓ KFT

PHILIPPE ABGRALL, RESEARCH MANAGER , AXON’ MECHATRONICS CHANTAL LE GRAET, R&D ENGINEER , AXON’ MECHATRONICS SANDRINE HERMANT, MARKETING MANAGER , AXON’ CABLE

In a vehicle, connectors and electronic components must be watertight and resistant to vibration. As the vehicle's functionality, mainly electronic, continues to increase, the available space is becoming smaller. More embedded electronics means more printed circuit boards and accompanying interconnects. Reliable supports, such as leadframes, are essential to accommodate these electronic components. Solutions exist to connect them in a space that is becoming more and more restricted. WATERTIGHT CONNECTORS In a car engine environment or in exposed areas, connectors are subject to a variety of conditions: temperature, humidity, immersion, and pollution by dust and fluids such as water, glycol, oil, fuel, brake fluid, and diesel exhaust fluid (e.g., AdBlue). To avoid pollution and infiltration, connectors must be watertight to maintain the integrity of the electronic systems. Communication between the sensors and the ECU (electronic control unit) must be ensured throughout the life of the product. This is especially true for autonomous or semi-

autonomous driving functions, including safety systems and anti-lock brakes.

As much as systems are developed to be watertight when connected, watertightness is not guaranteed when they are disconnected. Fluid infiltration, whether along cables or along electrical contacts, can occur even with overmolding that should protect the assemblies. Connectors made of a combination of plastic and metal parts show leakage rates for relatively low- pressure differentials, but also show a strong deterioration of the sealing performance during aging. This is when problems can occur. Technical solutions to avoid these issues involve materials, design, and quality controls during the connector manufacturing process. Combined chemical and mechanical solutions help achieve the required performance for a reasonable price. The design of the electrical contacts, made of metal, favors adhesion with a plastic insulator. The surface preparation improves the bonding of the plastic on the metal or on the plastic during the double operation of overmolding.