JPS56138253A - Period measuring instrument - Google Patents

Abstract

PURPOSE:To measure with high accuracy a period of a high speed pulse by a simple circuit, by constituting an instrument using a delay line having a lot of delay outputs which are individually different depending on an input signal, a register and an encoder. CONSTITUTION:A signal of the input terminal 1 is input to the binary-code circuit 2, and is binary-coded by a level according to the output of a level adjusting circuit of binary-code 6. Subsequently, it is input to a delay line 3 having a lot of delay outputs which have been finely split. As for the output of this delay line 3, the output state of the delay line 3 is stored by the edge of an output signal waveform of the binary-code circuit 2 through the register 4. That is to say, when seeing the output state of this register 4, a delay time of the output which has the shortest delay time and has shown ''1'' level shows a period between pulses. Also, the output of this register 4 is changed to a necessary code through the encoder 5 and is output to the output terminals 7A...7D. According to such a constitution, a period of a high speed pulse is measured with high accuracy and also continuously in a real time by use of a simple circuit.