| 摘要 |
PURPOSE:To produce a plastic sealed photocoupler having a structure which prevents infiltration of external ionic impurities, by shortening the shortest distance between a lead frame connected with a light emitting device and a lead frame connected with a photosensitive device compared with the shortest distance between the light emitting device and the photosensitive device. CONSTITUTION:In a photocoupler which comprises a light emitting device 2, a photosensitive device 3 opposite thereto and lead frames 4-7, and is sealed with a plastic package 1, the shortest distance between a lead frame 4 or 5 connected with the light emitting device 2 and a lead frame 6 or 7 connected with the photosensitive device 3 is further shortened compared with the shortest distance between the light emitting device 2 and the photosensitive device 3. For example, the section A of the lead frame 4 connected with the light emitting device 2 and the lead frame 6 or 7 connected with the photosensitive device 3 are neared and spaced 0.3mm apart each other. Similarly, the section B of the lead frame 7 connected with the photosensitive device 3 and the lead frame 4 or 5 connected with the light emitting device 2 are neared and spaced 0.3 mm apart each other. On the other hand, the shortest distance between the light emitting device 2 and the photosensitive device 3 is set to 1.5 mm. Under this condition, the whole structure is sealed with epoxy resin. |
