An electronic apparatus includes metal wiring plates placed together in the same plane to provide a wiring circuit, electronic devices mounted to the wiring plates through a solder, a case having a base portion and columnar portions extending from the base portion. The wiring plates are fixed to the columnar portions such that the wiring circuit is spaced from the base portion. The wiring plates have an enough thickness to resist a large current for operating the electronic devices and to release heat generated by the electronic devices. The wiring circuit is spaced from the base portion of the case so that the heat generated by the electronic devices is released in the space efficiently. The electronic devices are soldered to the wiring plates at once in a thermal reflow process.