Experimental investigation of the current-dependent electrical contact resistance of gold-plated flexible pins within connectors

For high-speed backplane connectors, it is necessary to achieve low and stable electrical contact resistance. This study experimentally investigates the electrical contact behavior of gold-plated flexible pins in connectors. Nonlinear variations in contact resistance (Rc) as a function of loading force (Fc) with a constant current are observed and analyzed. The effects of test currents (100 μA, 1 mA, and 10 mA) on the Rc-Fc characteristics are systematically compared. The results indicate that an increase in the current level can enlarge the real electrical conduction area, further reducing contact resistance. The observed decline in contact resistance is attributed to localized thermal effects induced by higher currents.