| 摘要 |
PURPOSE:To detect a constant period pulse signal and to know the period of a constant period pulse signal as well with a sub-shift register number by combining a main shift register with a sub-shift register and investigating the contents of the sub-shift register. CONSTITUTION:When a pulse column is inputted to an input terminal 1, it is compared with a constant threshold by a shaping circuit 2 and converted to the logic level signal of logic values 1 and 0. The signal is supplied to a synchronizing circuit 3 and outputted as a synchronizing pulse signal. The synchronizing pulse signal is supplied to a main shift register 4. The output of the synchronizing circuit 3 is inputted by a control circuit 5 and the control circuit 5 synchronizes with a clock signal and outputs a shift action instruction signal to respective sub-shift registers of a sub-shift register group 6. At this time, for the sub-shift register of the integer-fold number of the period of the constant period pulse signal, the logic value 1 more than other sub-shift register is inputted. Consequently, by investigating the contents of the sub-shift register, the constant period pulse signal can be detected. |
