CHARACTERISTICS MEASURING APPARATUS OF PULSE SIGNAL

PURPOSE:To reduce measuring errors, by measuring the pulse width and interval at a level dropped by a specified value from the peak level of a pulse signal to eliminate the effect of the rising and falling time thereof. CONSTITUTION:A level computing circuit 18 detects the peak amplitude value of an input pulse signal A/D converted 16 and a rise or a fall in the amplitude. A threshold (SH) detection circuit 21 performs a SH detection for distinguishing noises from signals depending upon whether the peak amplitude value is larger than a fixed value. When the pulse signal is smaller than the SH signal, the circuit 18 outputs a clock pulse as memory command signal and a digital value is memorized sequentially into a level memory circuit 23 while a time value is memorized into a time memory circuit 26. In addition, when the pulse signal exceeds the SH signal, a fixed level detection circuit 27 detects that the digital value drops by a certain level from the peak amplitude value and the time is memorized into a falling time register 29. Thus, the contents of the memory circuits 23 and 26 are read out sequentially and measured values are outputted from a pulse width calculation circuit 36 and a pulse interval calculation circuit 37.