| 摘要 |
PURPOSE:To decrease the scale of a conversion circuit by detecting only a level inverting point caused during a period when a CMI signal represents a zero code, shaping a ulse width of a pulse signal representing the level inverting point to generate an NRD signal. CONSTITUTION:A low level voltage signal L is supplied to a data input erminal D in a FF 1, a coded mark ivnersion (CMI) signal is inputted to a clock input terminal C and a clock signal 1 having a period T0 is inputted to a set terminal S. Further, a signal Bn sent from the FF 1 is inputted to the input terminal D of a FF 2 and a non return to zero (NRZ) signal read by using a clock signal 2 at a period T0 is sent. The output of the FF 1 is brought into a high level voltage by using the signal 1 at the level inversion caused at the changes of the CMI signal codes. In reading the signal Bn at the pulse leading of the signal 2 by the FF 2, the signal is converted into the NRZ signal comprising the same code series as that of eh CMI signal inputted to the FF 1. Thus. the circuit scale is decreased and the conversion is attained.
|
