Abstract: An electronic device includes an electronic component including a plurality of terminals and a circuit board on which the electronic component is mounted. The circuit board includes a board body, a plurality of electrode pads arranged on the board body, each of the electrode pads being connected to each of the terminals by solder, a first solder resist formed on the board body and having a plurality of first openings, each of the first openings accommodating each of the electrode pads, and a second solder resist formed on the first solder resist and having a plurality of second openings, each of the second openings being larger than each of the first openings and communicating with each of the first openings.

Abstract: A wiring board unit includes a connector having a plurality of terminals; and a wiring board on which the connector is mounted. The wiring board includes a first wiring pattern provided on a first wiring layer, a second wiring pattern provided on a second wiring layer at a position shallower than the first wiring layer, a first via formed in a first recess having a first depth, the first via being in contact with the first wiring pattern, and a second via formed in a second recess having a second depth that is smaller than the first depth, the second via being in contact with the second wiring pattern.

Abstract: The present invention is an electrode 10 so provided as to be soldered to an electronic component 12 and, when the electronic component 12 is mounted on a substrate 13, soldered to the substrate 13. The electrode 10 includes a column-like electrode body 11 soldered to the electronic component 12 and to the substrate 13. The electrode has grooves as an air discharging device discharging the air 15a in air voids 15 generated within the solder 14 between joint surfaces 11a, 11b of the electrode body 11 and the electronic component 12 or the substrate 13 when the electrode body 11 is soldered to the electronic component 12 or the substrate 13.

Abstract: The present invention is an electrode 10 so provided as to be soldered to an electronic component 12 and, when the electronic component 12 is mounted on a substrate 13, soldered to the substrate 13. The electrode 10 includes a column-like electrode body 11 soldered to the electronic component 12 and to the substrate 13. The electrode has grooves as an air discharging device discharging the air 15a in air voids 15 generated within the solder 14 between joint surfaces 11a, 11b of the electrode body 11 and the electronic component 12 or the substrate 13 when the electrode body 11 is soldered to the electronic component 12 or the substrate 13.