Circuit board, electronic device having the circuit board and method of manufacturing the electronic device

An electronic device, comprising:

• a circuit board including
• a substrate having an upper surface and a lower surface opposite to each other, and an insertion hole extending through said upper surface and said lower surface, said substrate including a base layer and two copper foil layers respectively covering upper and lower sides of said base layer and respectively serving as said upper surface and said lower surface of said substrate, said insertion hole having an expansion hole portion and an insertion hole portion connected to and communicating with each other, said insertion hole having a maximum width measured from one end of said insertion hole portion passing radially through the center of said insertion hole portion and the center of said expansion hole portion to one end of said expansion hole portion that is radially opposite to said one end of said insertion hole portion, said maximum width being greater than a hole diameter of said insertion hole portion, said hole diameter of said insertion hole portion being greater than a hole diameter of said expansion hole portion, and
• a conductive layer disposed in said insertion hole and electrically connected to said copper foil layers;
• and
• an insert member inserted into said insertion hole of said circuit board and including an axially extending terminal post, at least two protruding arms extending radially and outwardly from two diametrically opposed sides of said axially extending terminal post and resting on said upper surface of said substrate, and at least two protruding legs that extend upwardly and inclinedly from said two diametrically opposed sides of said axially extending terminal post, that are spaced apart from and located below said protruding arms and that abut against said lower surface of said substrate, a maximum distance measured from a free end of one of said at least two protruding legs to a free end of the other one of said at least two protruding legs being smaller than said maximum width of said insertion hole but greater than said hole diameter of said insertion hole portion.