AUTOMATIC REGULATING DEVICE FOR INPUT/OUTPUT OF VOLTAGE OF MIXED VOLTAGE APPARATUS

PURPOSE: To provide an automatic regulator for inputting-outputting the voltage across a mixed voltage digital electronic device. CONSTITUTION: An automatic regulator for interfacing with the voltage of a mixed voltage device is provided with an analog multiplexer 32, a sample hold circuit 34, and a voltage computing element 36. The multiplexer 32 has many inputs and one output and the output of the multiplexer 32 multiplexes one of the inputs given from one of logic circuit parts 10. The sample hold circuit 34 receives the output of the multiplexer 32 as a sample input and holds the sample input. The voltage computing element 36 is provided with many voltage sources respectively connected to many sample-held power supply voltage inputs, many control bit inputs given from the logic circuits of a digital logic system, and voltage sources required by the parts 10 of the digital logic system for appropriate operations.