| 摘要 |
PURPOSE:To make it possible to make the input current of a differential amplification part small and also to minimize the error of an output voltage to an input voltage by composing the circuit of 1st and 2nd differential input stage elements arranged symmetrically with a common emitter. CONSTITUTION:The circuit consists of left half 54 and right half 58 constituting voltage follower circuits respectively and are composed of differential input stage transistors TrQ1 and TrQ4, and TrQ8 and TrQ10 with common eitters arranged symmetrically, constant-current supplies 51 and 55, load elements 52 and 56 composed of TrQ2 and TrQ3, and TrQ7 and TrQ9 constituting current Miller circuits, and output TrQ5 and TrQ6. In this constitution, the offset voltage of the differntial amplifier composed of Trs Q1 to Q5 causes an error of linearity of this circuit, but the error is 0.164% and one-figure smaller than 1.3% of a conventional emitter degenerative amllifier. As for TrQ1, input current Iinl of 50A is nearly constant and much less and excellent in comparison with 0-2muA of the conventional emitter degenerative amplifier and 20muA of a Van de Plasche circuit. |
