| 摘要 |
PURPOSE:To obtain frequency responding characteristics of wider band width under all operational conditions, by controlling the electric current flowing into a control winding with a driving circuit. CONSTITUTION:A voltage lamp generator containing differential amplifiers U1 and U3 operates as a pulse width modulator, and periodically impresses voltage pulses which vary along with differences between a detection output voltage VR and a controlling voltage VC of the secondary winding 16 of an output transformer T upon a control winding LCA. The rectangular voltage pulse which is impressed upon the winding LCA and whose width varies, is synchronized to the chopping of a chopper circuit 10 and the pulse generating time varies depending upon the time where the VC and VR intersect. Therefore, since the voltage pulse has a frequency which is different from the chopper frequency, and the pulse source of the product of voltage and time depending upon the difference between the VR and VC is used as a controlling voltage, and the necessity of connecting condensers to the windings LCA and LCB is eliminated, responding characteristics of wider band width are obtained. |
