Printed circuit board, magnetic disk apparatus with the printed circuit board, and method for connecting the printed circuit board

摘要

A bump of an electrically conductive metal protrudes from an electrode pad of a junction FPC. The bump includes a lead portion that penetrates a conductor pattern and a base layer of the junction FPC and projects on the back side of the base layer. A spare solder layer is formed on the surface of the bump. In soldering the electrode pad of the junction FPC to a connecting pad of a main FPC, the bump and the connecting pad are opposed to each other, and a heat source is pressed against the lead portion of the bump from the side of the base layer of the junction FPC. Heat is transmitted to the spare solder layer through the lead portion and the bump, whereupon the spare solder layer is melted for soldering.