| 摘要 |
PURPOSE:To decrease the number of elements to facilitate the integration as well as to increase the accuracy, by using a current mirror circuit without applying an operational amplifier. CONSTITUTION:The voltages V1 and V2 are applied to the bases of the 1st and 2nd input transistors (TRs) 9 and 10 from the 1st and 2nd variable voltage sources 1 and 2 respectively. A current I1=(V1-V2)/R1 flows to the TR 9 and TR 10. At the same time, a current I1 is supplied to the collector side of a TR 11 which forms a pnp current mirror circuit, and a current AI1 is supplied to the collector side of a TR 12 of the other side. In addition, a current AI1 flows to the collector side of a TR 14 forming an npn current mirror circuit, and a current ABI1 flows to the collector side of a TR 13 of the other side. Then the voltage V0=I1XR2=R2(V1-V2)/R1 is led out of a load resistance 5 at the collector side of a TR 15. |
