| 摘要 |
PURPOSE:To obtain high output impedance while improving the precision of an input-output current ratio, by supplying the base current of transmistor TR of a current source circuit as emitter currents of two TRs added for biasing. CONSTITUTION:In the circuit consisting of TRs 12 and 11 cascaded to input signal source 13, output-side TR17-TR2n+15 cascaded, and TR16-TR(2n-1)+15, TR14 is connected at base B to collector C of TR12 and C is connected to potential source V2<+>; and base B of TR15 connected to B of TR12 and emitter E of TR14, C is connected to potential source V<+>, and E is further connected to Bs of TR16 and TR11. Then, B currents of TR12 and TR17-TR2n+15, and TR11 and TR16-TR(2n+1)+15 are supplied as E currents of TR14 and TR15 added for biasing to improve the precision of the input-output current ratio, and further those two TRs constiture a Darlington-connected feedback circuit, so that high output impedance can be obtained. |
