The objective of the present invention is to improve reliability in a solder connection portion between an electronic component and a wiring pattern. A pair of wiring patterns (31A and 31B) are formed on a circuit wiring board (30) with an insulation layer (37) therebetween. Each wiring pattern (31A and 31B) has a land (33a or 33b) and a wiring portion (34a or 34b) that is narrower than the land. By way of solder (42), a chip component (41) is soldered to the lands (33a and 33b). The x (width) direction center (Xa) of each connection portion (53) where a respective wiring portion (34a or 34b) is connected to a respective land (33a or 33b) is disposed at a position that is outside of both the region in which a region of predetermined width (Wc) of the chip component (41) extends in the x (longitudinal) direction, and the region in which a region of predetermined length (Lc) of the chip component (41) extends in a y (transverse) direction.