| 摘要 |
PURPOSE:To attain possibly low voltage operation by applying switching signals either one of which is nearly the same potential as the power supply potential without fail to each common base of two pairs of differential pair transistors (TRs). CONSTITUTION:The two pairs of the differential pair TRs 16, 17; 18, 19 are of the doubly balance circuit constitution having constant current sources 11, 12 and output load resistors 22, 23. Further, the output of the differential pair TRs is connected to a 4-bit ring counter 33 via TRs 31, 32 for relaying switching signal. When the output at terminals Q1 and Q3 of the counter 33 is both logical 0, the TRs 31, 32 are turned both off and both collector potentials are nearly equal to the potential Vcc of the power supply 15. The signal of each common emitter of the two pairs of differential pair TRs 16, 16; 18, 19 of the doubly balance circuit constitution playing a role of switching operation by the collector output of the TRs 31, 32 is not dropped to a potential or below, being the subtraction of a base-emitter voltage VF of the TR from the potential Vcc. |
