Complementary transistor inverting emitter follower circuit

Abstract

A complementary bipolar transistor circuit characterized by the same output impedance for positive and negative input voltage transitions, only a single collector path delay between input and output for both senses of input voltage transitions and very low standby power consumption. Provision is made for simultaneously actuating an emitter follower series-connected first pair of complementary transistors with signals having voltage swings which are only a fraction of the V.sub.be necessary to forward bias each base-emitter diode of the first pair of transistors. The actuation is accomplished using a second pair of complementary transistors having collector electrodes connected to respective bases of the first pair of transistors of similar kind. One of the remaining electrodes of each of the second pair of transistors are connected to each other. In a driver circuit species of the invention, the bases of the second pair of transistors are connected to each other and receive the input signal. In a logic circuit species of the invention, the emitter of one of the second pair of transistors is connected to the base of the other of the second pair of transistors. NOR logic is performed by connecting additional transistors in parallel with said one of the second pair of transistors, the bases of the additional transistors receiving respective logic input signals. The output from the driver circuit as well as from the logic circuit is derived from the commonly connected emitters of the first pair of transistors. The first pair of transistors conduct only during the transitions of the input signals.