METHOD AND DEVICE FOR ISOLATING NOISE SENSITIVE CIRCUITRY FROM SWITCHING CURRENT NOISE ON SEMICONDUCTOR SUBSTRATE

摘要

PURPOSE: An apparatus and a method for isolating a noise sensitive circuit from switching a current noise in a semiconductor substrate are provided to isolate an electric noise generated from a current change of an I/O pad without changing the I/O pad. CONSTITUTION: A data combination circuit(40) is controlled by a control signal of an output driver enable signal generator(42). The data combination circuit(40) connects electrically an inner data bus(18) to an inner device data bus(32) or an outer device input bus(30). The output driver enable signal generator(42) receives a data output control signal, a reset signal(14), and an outer device signal(34) and generates an output driver enable signal(56). An input driver enable signal generator(44) receives a data input control signal and a device selection signal(50) from a data transmission control bus(20) and generates an input driver enable signal(48).