Patent ID: 8077472

Claim:
A printed circuit board, comprising: a main body defining a through hole configured for being connected to a grounding component, wherein a fixing member is passed through the through hole of the printed circuit board, and engages with the grounding component, the main body includes a first copper layer, a first steel layer, a grounding layer, a second steel layer, and a second copper layer, arranged in that order, a plurality of first tin pads are positioned on the first steel layer, and protrude out of the first copper layer, a head portion of the fixing member abuts the first tin pads, the fixing member is electrically connected with the grounding layer, and a plurality of second tin pads are positioned on the second steel layer, and protrude out of the second copper layer; a tin layer formed on a surface of the main body around the through hole for contacting the grounding component, wherein the tin layer covers the second tin pads; and a solder mask formed between a periphery of the through hole and the tin layer, wherein the solder mask prevents tin cream of the tin layer from flowing into the through hole.