ELECTRONIC BOARD UNIT

摘要

Second display means front parts, each including an immersion liquid surface level display for a coating liquid for moisture prevention and a lead-free display mark, are formed respectively in upper portions on a left side and a right side that are opposite sides having the one side interposed therebetween. A first display means front part including a board management document number, which defines a material for solder, is formed in a lower portion of the printed circuit board. A lead-free display mark (PBF) is not buried in or mixed with a large number of circuit information displays in the board, and a detailed management number is described in a reduced size to conserve space. Thus, the important lead-free display mark can be displayed with large character marks that also serve to manage a liquid surface.

主权项

1. An electronic board unit, comprising:
a printed circuit board having a connector mounted on one side thereof, the printed circuit board including, on one of a front surface and a back surface thereof, one of front circuit components and back circuit components, which are all soldered onto the printed circuit board through lead-free solder having a low lead content rate; first display means formed along one of an opposite side parallel to the one side of the printed circuit board and at least one of opposite sides orthogonal to the one side of the printed circuit board; and a pair of second display means formed respectively along a left side and a right side that are the opposite sides orthogonal to the one side of the printed circuit board, the first display means serving as design information display means for displaying, with characters, a board management document number that defines at least a material for applied solder through use of a solder resist film applied to one of the front surface and the back surface of the printed circuit board, the pair of second display means displaying a lead-free display mark that indicates at least that a lead content of the applied solder is less than a predetermined value through use of a solder resist film applied to one of the front surface and the back surface of the printed circuit board, the lead-free display mark being positioned close to a position at which the connector is mounted and also serving as operation information display means that includes an upper limit position display and a lower limit position display, which indicate an appropriate amount level range of a coating liquid for moisture prevention when the printed circuit board is immersed in a hot-dipping bath so that the coating liquid for moisture prevention is applied to the printed circuit board.