Compliance metrics for the inclined gull-wing, spider J-bend, and spider gull-wing lead designs for surface mount components

A wide variety of plastic and ceramic SM devices have complaint gull-wing leads for circuit board interconnection components. The compliance metrics are quantified for specific inclined gull-wing and spider J-bend lead designs. The inclination angle in the gull-wing lead design determines the lead height, as well as the overall lead footprint on the circuit board. The directional stiffness of a representative gull-wing lead design has been parametrically evaluated with respect to the lead inclination angle. An overview of the previously developed formulation for directional lead stiffness has been provided as a technical foundation for the current application. The lead stiffness metrics for a commercial thermocompression-bonded spider J-bend wire lead have been evaluated over a wide range of typical lead weights and the results compared with a commercial S-bend soldered clip lead