| 摘要 |
PURPOSE:To make DC potentials of two signals different in phase coincide with each other easily, by comparing DC potentials of two signals output from the differential amplifier, and controlling a current flowing into the differential amplifier, by an error signal. CONSTITUTION:Two signals different in phase by 180 deg. are picked up from the collectors of the differential transistors (TR)T1, T2. In this case, for instance, if mismatching exists between the resistors R4, R5, the error voltage is generated between DC potentials of two signals. This error voltage is detected by the TRs T5, T6 for comparing circuit, the AC signal is removed by the collector of the TR T5, and when only the DC signal is fed back to the base of the TR T4 for constant- current, the current I4 is controlled, and the error voltage caused by mismatching is corrected. In this way, DC potentials of two signals is made to coincide to each other easily. |
