New-Tech Europe Magazine | Dec 2017

Connectors & Cables Special Edition

Figure 2: Brass is commonly used in connector options that do not requre movement. See the weld tab (bottom right) on this micro edge card socket.

Figure 1: Plastic accounts for a greater percentage of the total connector cost in a micro pitch interconnect.

Phosphor Bronze Phosphor bronze is stronger than brass and has better spring properties. But, its spring properties aren’t as good as BeCu, so it is not frequently used in micro pitch connectors. Phosphor bronze is well-suited for bigger contact systems with longer beams with more deflection (see Figure 3). What Plating Option Do We Recommend? Choosing the right plating is critical to the success of a connector system. Plating affects the connector’s performance, life cycle, quality, and cost. Designers frequently ask what plating finish we recommend? There are numerous considerations to take into account, but the best plating finish is whatever meets your

beam will not properly mate with the socket. Samtec uses brass components on some connector products, but they are for options what don’t bend or require movement, like the weld tabs on a micro edge card socket. (See Figure 2) Beryllium Copper Beryllium copper, while more expensive thanmost contactmaterials, provides the best combination of mechanical and electrical properties. Once formed and hardened, BeCu will retain its shape under a wide variety of conditions. And because BeCu springs back after cycling, it’s a great pin material for miniature connectors. So BeCu is good for rugged and high- cycle applications, and it’s good for micro connectors.

Figure 3: Phosphor bronze is well-suited for contact systems with longer beams

New-Tech Magazine Europe l 43