| 摘要 |
PURPOSE:To attain a highly reliable optical transmission/reception circuit and low part consumption by applying variable control to the output power of optical transmission of a light emitting element such that the optical reception input power of a photodetector is a desired setting value. CONSTITUTION:A data and a clock supplied respectively to input terminals 11, 12 of an optical transmission section 1 are supplied to an end face radiation type LED 13 through a drive circuit 2, and is subject to electrooptic conversion. An optical signal radiated from the end face radiation type LED 13 is received by an avalanche photodiode (APD) 15 of a photodetection section 5, where the signal is subject to photoelectric conversion. A signal subject to photoelectric conversion by the APD 15 is fed to a main amplifier 17 trough a preamplifier 16. A signal amplified up to a required level by the main amplifier 17 is extracted of the timing by a timing amplifier 18 and the result is fed to an identifying circuit 19, while the signal is fed directly to the circuit 19. Thus, the circuit 19 discriminates the data and the clock from the input signal, and outputs separately the data and the clock to output terminals 20, 21. |
