An electronic apparatus of the present invention has a first unit and a second unit coupled to the first unit through a coupling section which allows the second unit to be opened and closed relative to the first unit and the second unit has a display screen with a pen input function for detecting the contact of a pen or the close position of a pen. The first unit includes a bottom cover, a circuit substrate arranged above the bottom cover, and an upper cover arranged above the circuit substrate. The circuit substrate has a DC-DC converter that is disposed thereon and provided with one or more coils that generate power for operating the electronic apparatus, and at least one of the coils is disposed on the surface of the circuit substrate facing the bottom cover.