三值四态门的TTL电路实现

The Implement of Ternary Quadristate Gate in TTL Circuits

本文首先分析了以电阻为集电极负载的三值TTL输出级电路，根据开关模型，建立了含有四个状态输出的三值TTL输出级电路，并讨论了该电路中的晶体合开关元件与信号间的相互作用过程，补充了文献[2]提出的限幅电压开关理论。通过实例提出了基于限幅电压开关理论的三值四态门的TTL电路设计方法。

In this paper, the ternary TTL output circuit with resistance as collector load is analysed,the ternary TTL output circuits with quadristate are established by switching model. In the circuits, the interactions between transistor switching element and signals are discussed, and the theory of clipping voltage switches in reference is complemented,and the design method of the circuits of ternary TTL quadristate gate based on the theory of clipping voltage switches is presented by some examples.