Temperature-compensated amplifier circuit

摘要

A temperature-compensated amplifier circuit including an amplifier section having first and second transistors which are connected at their collectors to a power source terminal through first and second resistors, and having d.c. biased bases coupled to signal source terminals; a current source including a third transistor having a collector coupled with the emitters of the first and second transistors and a grounded emitter; a fourth transistor having an emitter coupled with the power source terminal through a third resistor; a fifth transistor connected at the emitter to the power source terminal and at the base to the base of the fourth transistor; a sixth transistor having both base and collector commonly coupled to the collector of the fourth transistor and grounded at the emitter; and a seventh transistor connected at the collector to the base and the collector of the fifth transistor, at the base to the bases of the third and sixth transistors and grounded at the emitter. The emitters of the sixth and seventh transistors are formed so as to have a predetermined area ratio thereby controlling the current in the forth and fifth transistors. The first to third resistors are formed to have substantially equal temperature characteristics.