| 摘要 |
PURPOSE:To obtain an output by a sufficiently large amplitude level by constituting an output stage of an MOS amplifier circuit with an MOS inverter amplifier and applying a local negative feedback thereto so as to reduce an output impedance. CONSTITUTION:An output O1 of a differential amplifier circuit is inputted to a gate of an MOS19 acting like a driver MOS, at the output stage, where the output O1 is amplified inversely and outputted as an output O2. An MOS20 acts like a load MOS. Suppose that a load connected to an output terminal 8 is fluctuated, a load current is increased and a voltage of the output O2 is decreased, then a gate voltage of an N channel MOS16 is decreased and a source voltage O3 of the MOS16 is decreased. That is, a gate voltage of the load MOS20 at the output stage is decreased, resulting that a drain-source voltage of the MOS20 is increased, thereby increasing the output voltage O2. Thus, a negative feedback is applied to the output O2 depending on increase/ decrease in the load current, allowing to reduce the output fluctuation. That is, the output impedance is decreased. |
