| 摘要 |
A bipolar transistor circuit is disclosed, which receives input voltage signals and outputs a current of a polarity in accordance with the input signals and of a predetermined amplitude. This circuit includes a first current source producing a first reference current, an output terminal, bipolar switching transistors coupled between the first current source and the output terminal and controlled by the input voltage signals to supply to the output terminal an output current of a first polarity which has an amplitude of the first reference current minus a base current of the switching transistor or integer times of that amplitude, a current producing circuit producing a current that is substantially equal to the base current of the switching transistor, and a second current source connected to the output terminal and producing a second reference current of a second polarity which has an amplitude of the first reference current minus the amplitude of the current produced by the current producing circuit. The present invention thus provides a well-balanced output current which is suitable to charge and discharge a load capacitor with the same amount of charges. |
