| 摘要 |
<p>PURPOSE:To improve an integration density, by inputting input signals at a plurality of different frequencies, and selectively detecting the signals. CONSTITUTION:Light beams are projected on a large scale logic integrated circuit on a substrate 1 from a light emitting element 2 with a wavelength fA and a light emitting element 3 with a wavelength fB. Meanwhile, optical detectors 4 and 5 are arranged at places, where synchronizing signals are required in the logic integrated circuit. The detecting wavelengths of the optical detectors 4 and 5 are changed in correspondence with the kinds of the synchronizing signals. As a result, for the light signal having the wavelength fA, several detectors 4 are operated. For the light signal having the wavelength fB, the group of the other detectors 5 are operated. In this way, the wavelengths for the light signals are prepared in correspondence with the number of the input signals. The detectors 4 and 5 are also prepared in correspondence with the number of the input signals. Thus the arbitrary synchronizing signal can be transmitted to an arbitrary place in the integrated circuit. Since a plurality of the synchronizing signals can be inputted to any places on the LSI without delay, the level of integration is improved.</p> |
