Fall Chinook Salmon in the South Fork Coos River: Spawner Escapement, Run Reconstruction and Survey Calibration

An output circuit which hardly causes ringing etc. in its output waveform even if a high capacity load is driven at a high speed comprises an input terminal (11), an output terminal (12), an output driving circuit (5) controlled by a signal received in the input terminal (11), and voltage drop means (6) connected between an output terminal (10) of the output driving circuit (5) and the output terminal (12). The output driving circuit (5) is formed by connecting a circuit having high current drivability and that having small current drivability in parallel with each other, to have large current drivability when change of an output voltage is started while having small current drivability at a terminating point of the change. While ringing is suppressed by the output driving circuit (5), it is possible to obtain an output circuit which hardly causes ringing in its output waveform as well as undesired radiation also by optimizing current drivability and output impedance of the output circuit by the voltage drop means (6) in response to a load connected thereto and driving an output buffer of a logic circuit at a high speed.