| 摘要 |
PURPOSE:To attain highly accurate oscillating angle frequency in an oscillation circuit by integrating an output of the 1st amplifier circuit of current drive output type, amplifying the integration output with the 2nd amplifier circuit of current drive output and feeding back the output to the 1st amplifier circuit. CONSTITUTION:The DC component of an input signal vs of the 1st amplifier circuit 211 of current drive output type is cut off by the 1st capacitor Cs and the output of the 1st amplifier circuit 211 is integrated by the 2nd capacitor C1. The integration output of the 2nd capacitor C1 is inputted to the 2nd amplifier circuit 212 of the current drive output type and its output is fed back to the input terminal of the 1st amplifier circuit 211. According to the phase shift circuit, an output voltage vc whose phase is lagged by 90 deg. than that of the input voltage va and whose DC level is coincident with a fixed voltage V1 is obtained. Thus, the problem of the fluctuation of an oscillated angular frequency omega attended with the DC level fluctuation of the output of the phase shift circuit is solved.
|
