Photocoupler

A photocoupler comprising:

• first to fourth leads provided with a planar arrangement, the first to fourth leads being apart from each other and each having an upper surface, a lower surface and a side surface, the side surface being connected to the upper surface and the lower surface around outer peripheries of the upper surface and the lower surface, the third lead being adjacent to the fourth lead,
• a first MOSFET provided on the upper surface of the third lead, the third lead being electrically connected to a drain of the first MOSFET,
• a second MOSFET provided on the upper surface of the fourth lead, the fourth lead being electrically connected to a drain of the second MOSFET,
• a semiconductor light receiving element having a front surface and a back surface, the semiconductor light receiving element being bonded to the first and second MOSFETs at the back surface side, the first MOSFET including a portion provided between the semiconductor light receiving element and the third lead, the second MOSFET including a portion provided between the semiconductor light receiving element and the fourth lead, the semiconductor light receiving element having a first output electrically connected to gates of the first and second MOSFETs and a second output electrically connected to sources of the first and second MOSFETs,
• a semiconductor light emitting element provided on the front surface of the semiconductor light receiving element, the semiconductor light emitting element having a first electrode electrically connected to the first lead and a second electrode electrically connected to the second lead, and
• a resin layer sealing the first MOSFET, the second MOSFET, the semiconductor light receiving element and the semiconductor light emitting element, the resin layer further sealing the upper surfaces and the side surfaces of the first to fourth leads, the resin layer having a bottom surface in which the lower surfaces of the first to fourth leads are exposed to air, the lower surfaces of the first to fourth leads being in plane with the bottom surface of the resin layer.