| 摘要 |
PURPOSE:To decrease the number of input and output pins by providing an input circuit which generates two signals by a ternary level signal and an output circuit which converts the two signals into the ternary level signal. CONSTITUTION:A composite output driving circuit consists of N channel IGFETs (T1-T4). When data DA and DB have a high level, the FETs T2, T3 and T4 turn on and output data DC has low level. When the data DA has the high level and the DB has the low level, the FETs T2 and T3 turn on and the T4 turns off, so that the data DC has an intermediate level. When the data DA and DB have the low level, the FETs T2 and T4 turn off and the data DC has the high level. Further, the composite input receiving circuit composed of IGFETs (T5-T9) separates ternary input data by making the threshold voltages of the FETs T6 and T8 different. |
