Wiring substrate and method of manufacturing the same, backboard and display apparatus

A wiring substrate, comprising:

• a substrate;
• at least one conductive layer located on a side of the substrate;
• wherein a conductive layer includes a plurality of pad groups, and a pad group includes a plurality of conductive pads;
• and
• a protective layer located on a side of the at least one conductive layer away from the substrate;
• wherein the protective layer includes a plurality of openings;
• a portion of the conductive layer exposed by an opening is a conductive pad;
• wherein a maximum dimension of the conductive pad in a direction parallel to the substrate is greater than or equal to 1.5 times a minimum distance between an edge of the conductive pad and an edge of the conductive layer, and less than or equal to 30 times the minimum distance between the edge of the conductive pad and the edge of the conductive layer;
• wherein the at least one conductive layer includes a plurality of conductive lines, and a portion of a conductive line exposed by the opening is the conductive pad;
• the conductive line includes a main surface, and a plurality of side surfaces that are each connected to the main surface, and the main surface is a surface of the conductive line away from the substrate;
• and at least two side surfaces, that each have a small distance to the conductive pad of the conductive line, of the plurality of side surfaces are each a first side surface, and two first side surfaces are connected to each other via a curved surface.