| 摘要 |
<p>In an impedance and transfer characteristic measuring apparatus sine-wave and cosine-wave data are produced using data obtained by accumulating a fixed phase value in synchronism with a clock signal and the sine-wave data is provided to a device under test after D-A conversion. Multiplied outputs are obtained by multiplying type D-A converting part (60) which D-A converts the sine-wave data and the cosine-wave data, using two signals related to an item of measurement of the device under test as analog multiply inputs therefor. An integration control signal of a predetermined level is generated by a signal generating part (70) for the half-cycle period of a sine-wave test signal in synchronism with a measurement start signal. For the period during which the integration control signal is yielded the multiplied outputs are respectively integrated in an integration circuit part (110) to thereby obtain vector-detected outputs. The detected outputs are A-D converted, and based on the digital detected outputs, a calculating part (150) performs calculations related to the item of measurement.</p> |
