Lead assembly, electrical connector, printed circuit board and electronic system

An electrical connector, comprising:

• a housing comprising a mating surface having a slot extending in a longitudinal direction and a mounting surface opposite the mating surface;
• a plurality of first-type conductive elements aligned in the longitudinal direction, each of the plurality of first-type conductive elements comprising a mating contact portion curving into the card slot and a mounting tail opposite the mating contact portion and extending beyond the mounting surface, the mounting tail having a mounting end;
• and
• a plurality of second-type conductive elements, each of the plurality of second-type conductive elements comprising a mating contact portion curving into the card slot and a mounting tail opposite the mating contact portion and extending beyond the mounting surface, the mounting tail having a mounting end, wherein:
• each of the plurality of second-type conductive elements is disposed between respective first and second adjacent first-type conductive elements;
• and
• the mounting end of the mounting tail of each of the plurality of second-type conductive elements is disposed farther from the mounting end of the mounting tail of the respective first adjacent first-type conductive element than the mounting end of the mounting tail of the respective second adjacent first-type conductive element.

An electronic system comprising:

• a printed circuit board comprising a plurality of pads and a plurality of through-holes, each of the plurality of through-holes passing through a respective pad of the plurality of pads and sized in the range of 0.35 mm to 0.45 mm;
• and
• an electrical connector mounted on the printed circuit board, the electrical connector comprising:
• a housing comprising a mating surface having a slot and a mounting surface opposite the mounting surface, and
• a plurality of conductive elements, each of the plurality of conductive elements comprising a mating contact portion curving into the slot, a mounting tail extending beyond the mounting surface into a respective through-hole of the plurality of through-holes, the plurality of conductive elements configured to transfer data signals at rates in the range of 10 Gb/s to 150 Gb/s.