| 摘要 |
PURPOSE:To enable the measurement of a time range at a high speed and in real time with a pair of fraction time measuring circuit, by converting a fraction time into a voltage without resetting a time-voltage converter to perform a computation after an A/D conversion thereof. CONSTITUTION:When a start fraction time pulse is applied, a time-voltage converter 1 converts the period and time of a pulse width of the pulse to voltage and when upon the end of the pulse, a voltage value v1 to v2. The value of v1-v2 becomes a voltage proportional to the start fraction time. During this period, the converter 1 is operated without resetting it thereby enabling high- speed operation. Thereafter, a step fraction time pulse comes, a time-voltage conversion is done with the voltage v3 (v2=v3) previously held as starting point to obtain a voltage v3. This v3-v4 value is becomes a voltage proportional to a stop fraction time. These v1-v4 values are converted to a digital value with an A/D converter 5 and applied to processor 6o through a latch circuit 7. The processor 60 are given v1-v4 and a voltage of a pulse width equal to a clock cycle to compute time.
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