DEVICE FOR CONFIRMING MOUNTING POSITION OF PACKAGE

PROBLEM TO BE SOLVED: To obtain a device for confirming mounting position of package with which a package can be easily mounted on a printed wiring board at the position corresponding to a pad, etc., with a simple mechanism when electrodes are arranged on the rear surface of the package in the state of a ball grid array. SOLUTION: Corner patterns 12 and BGA pads 13 respectively composed of pieces of copper foil formed by etching are arranged on a printed wiring board 11. On the pads 13, a ball grid array 14 is mounted so that the four corners of the array 14 can be aligned with the corner patterns 12. The width of each pattern 12 is set to the half of the width of the pads 13 for mounting the array 14 or narrower and the positional deviations of the patterns 12 when the patterns are reflow soldered can be corrected by self-alignment effects.