1. A power-supply device comprising:a casing;
a circuit board; and
at least one electronic component on the circuit board,
wherein the casing includes a casing portion having an opening, and a cover portion disposed to cover the opening of the casing portion,
the casing houses the circuit board between the casing portion and the cover portion, and
the cover portion includes a recess covering the at least one electronic component,
wherein the casing portion has a through hole formed at a position corresponding to a connector terminal connected to the circuit board, the casing portion includes a protruding portion that protrudes outward, a top face of the protruding portion is recessed, the through hole is located in the top face of the protruding portion.