INPUT CIRCUIT OF COMOS TYPE INTEGRATED CIRCUIT

摘要

PURPOSE:To secure effectively the level of a bus line by feeding back positively a part of the output of a CMOS type inverter connected to the bus line via a feedback inverter. CONSTITUTION:A bus line 1 is driven by output inverters 2 and 2', and the signals of IC10 and 10' are supplied to an input inverter 3 of an IC11. A part of the output of the inverter 3 is supplied to a feedback inverter 5, and the output of the inverter 5 is fed positively back to the inverter 3. Here the competitive driving is carried out between the inverter 2 or 2' and the inverter 5. In this case, the driving capacity of the inverter 2 or 2' is set larger several times than that of the inverter 5. Thus the information of the circuits 10 and 10' are correctly transmitted. As a result, the level of the line 1 can be fixed with use of a pull-up resistance and without flowing steadily a DC current.