| 摘要 |
PROBLEM TO BE SOLVED: To provide an emitter follower circuit 11 that acts like a buffer for impedance conversion or the like and can stably compensate a base current Ib of a transistor(TR) Q1 supplied to a load. SOLUTION: A compensation current generating circuit 12 comprises a constant current source F1 supplying a constant current to the emitter of the TR Q1, a constant current source F2 equal to the constant current source F1, and a TR Q2 equal to the TR Q1, and a capacitor C1 is provided between a power line and bases of mirror TRs Q4, Q3 in a current mirror circuit 13 to fold back a base current I3 of the TR Q2 to supply a compensation current to the base of the TR Q1. Thus, the base level is increased by a parasitic capacitance between the base and emitter of the mirror TR Q4 with respect to a rapid increase in the base voltage of the TR Q1 so as to prevent the mirror TRs Q3, Q4 from being nonconductive.
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