| 摘要 |
PURPOSE: To obtain a device which can quickly and accurately perform measurement by arranging first and second polarity inverters, a constant current source which generates a reference signal, etc., and controlling the second polarity inverter by using the same switching signal as that used for the first polarity inverter. CONSTITUTION: A device for converting electric polyphase signal into frequency is provided with a totaling circuit 2 and a first polarity inverter 1 at every phase. In addition, at least one second polarity inverter 5 is provided in the poststage of a voltage-current conversion circuit 3 and a constant-current source 15 which generates a reference signal IR/2 is arranged in the input section of one of the second polarity inverters 5. Then the second polarity inverters 5 are made to be controlled by the same switching signal as those used for the first polarity inverters 1. Therefore, the modulation of the output frequency of the device by the difference of the half-period lengths of the switching signals and the fluctuation of the output frequency of the device by the residual charge of a capacitor which still exists at the moment when the polarity is inverted can be prevented. |
