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combining signal and power in an efficient space-saving approach.
CHALLENGES OF EV High voltage and high current. EVs contain a multitude of high-current applications. The most demanding transfers of energy occur when the external charger sends large current flows into the onboard battery (up to 500 amps; ultra-fast chargers exceed 600 amps), when the battery’s stored energy is discharged to accelerate, when the inverter converts DC power to AC power for the electric motor, and when regenerative braking systems reverse currents back into the battery systems. High-current transfers also generate massive thermal dissipation within the EV itself, which could potentially impact the connections of nearby PCB components. EV vs. the elements. EV applications demand interconnect solutions that can endure extreme conditions across a vehicle’s lifecycle. Dirt, moisture, corrosion, and high vibration are everyday exposures for an automobile, but each poses a challenge for electrical components. Each of these factors can cause major disruptions in connections, if not properly planned for and avoided. Every system, whether signal or power, requires its own unique design solutions. However, beyond these individual design hurdles lies a broader, system-wide challenge of ensuring that all these distinct electronic subsystems, each with their own individual component layout and operating parameters, can function reliably without interference. All connections must be designed and accommodated in a manner rugged enough to withstand the external disturbances while minimizing the impact of close-proximity internal systems within the vehicle itself. The consequences of signal loss can range from minor annoyances to the failure of critical safety functions, depending on the system involved. How can PCBs maintain signal integrity at high speeds, manage substantial high power currents, resist thermal dissipation from neighboring systems, and tolerate extreme environments, all while packed close to one another? This is the challenge.
ept press-fit technology
Contacting solutions: press-fit Press-fit technology offers a solder-free solution for creating robust electro-mechanical connections on a PCB. Instead of relying on heat to create connections, press-fit connectors use controlled force to insert specially designed pins into plated through-holes on the board. The result is a reliable, gas-tight connection. Each pin is slightly larger than its corresponding hole. As it's pressed in, the rigid walls of the PCB remain unchanged, while the flexible design of the press-fit terminal absorbs the force and deforms in a precise engineered way. This forms a cold-welded connection at the atomic level, bonding the metal surfaces without melting them. Press-fit mating creates a robust connection without the risk of heat-related damage to surrounding components during the mating process. Press-fit technology also eliminates flux residues, the chemical byproducts left behind on a PCB after the soldering process that can vary in appearance, composition, and risk level depending on the type of flux used. There are also no lingering air pollutants from the solder vapors, so workers have no risk of exposure to evaporating solvents. Press-fit mating process easily complies with EPA, RoHS, REACH, and WEEE guidelines. There are a few important considerations when using press-fit technology. The PCB type and its thickness must be suitable for press-fit. The drilling diameter, the diameter of the metallized press-fit hole, and the thickness of the copper sleeve in the press-fit hole must be expertly designed to specification for the press-in
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