| 摘要 |
PURPOSE:To attain measurement of long time with a counter of less number of bits and to improve the accuracy at measurement for a short time by switching an adding value fed to an adder depending on the count. CONSTITUTION:When a signal is inputted to an input terminal 1, an output data of a RAM3 is inputted to an adder 4. When a signal from a selector 9 goes to logical 1, the data is increased by 1 and then stored again to the RAM3. Two signals having a different period are fed to input terminals 6, 7 of the selector 9, which is switched by the output of a comparator 8 to which the output of the RAM3 is inputted. That is, when the output of the RAM3 is smaller than a prescribed value, a signal with a short period is outputted and when larger, a signal with a long period is outputted. Thus, long-time measurement is attained with a counter of less number of bits and the accuracy at short time measurement is kept high. |
