| 摘要 |
PURPOSE:To propagate a signal between respective circuits by means of light by using through holes as light paths by a method wherein the through holes in a printed wiring board are arranged in positions corresponding to input/output ports of light of an IC and power-supply ground circuit interconnections used as respective reference potentials in electric-signal processing circuits of different qualities are separated. CONSTITUTION:IC' 10 are IC's for analog electric-signal processing circuit use; parts at output ports 12 of light and at input ports 13 of light are provided with conversion circuits which convert an electric signal and light, respectively. In addition, IC's 11 are IC's for digital electric-signal processing circuit use; parts at input ports 18 of light and at output ports 19 of light are provided with conversion circuits which convert an electric signal and light, respectively. That is to say, an analog signal processing circuit is constituted on one side and a digital signal processing circuit is constituted on the other side; these signals are propagated by means of light; light paths are through holes 30, 31. In addition, a power-supply ground circuit interconnection 23 as a reference potential of the analog signal processing circuit is separated from a power-supply ground circuit interconnection 24 as a reference potential of the digital signal processing circuit. |
