| 摘要 |
PURPOSE:To delete easily the input offset just by adding a single transistor having the same constitution as the transistor set at an input stage of a differential circuit. CONSTITUTION:The current values of current sources 7 and 8 are aet at I0 and I0/2, and the current mirror ratio between a diode 1 and a transistor (TR)2 is set at a single multiple. The collector current of TR6, i.e., the collector current IC2 is shown by an equation when the base voltage of both TRs 5 and 6 are set at an equal level. While the collector current of a TR11 has the same constitution of the TR6 of an input stage and is also shown by the equation. Therefore the current i0 flowing into and out of a signal modulator 13 is set at zero. Thus the input offset can be deleted. |
