| 摘要 |
PURPOSE:To avoid a switching phenomenon of a transistor (TR) for a complementary circuit by using the 3rd complementary pair TRs which is connected in parallel to the 1st complementary pair TRs and at the same time Darlington- connected to the 2nd complementary pair TRs respectively. CONSTITUTION:The 3rd complementary pair TRs 5 and 6 are connected in parallel to the 1st complememtary pair TRs 1 and 2 and at the same time Darlington-connected to the 2nd complementary pair TRs 3 and 4 respectively. An appropriate bias is applied between terminals 19 and 20 to cut off the TR5 while the TR1 is set under a signal transmission state. At the same time, the TR5 is active in a negative region of signal to turn off the TR1. While the TRs 2 and 6 of the other side have the same working with a shift pi set between them. In such a constitution of circuit, the variation of the current flowing to diodes 7 and 8 is reduced down to 1/hfe (hfe: current amplification factor of TRs 5 and 6) and the bias fluctuation is reduced. Thus it is possible to supply a non-cutoff base current for TRs 3 and 4 by selecting an appropriate current power amplification factor of the TRs 5 and 6 respectively. Thus, a non-cutoff power amplifier even with a two-tier Darlington connection can be constitured. |
