Fault detection of combinational circuits based on supply current

A fault detection technique is proposed which can detect logical faults in combinational circuits by measuring the supply current instead of the output logic, and the effectiveness is evaluated by experiments of the circuits made of TTL (transistors-transistor logic) ICs. This technique is based on the assumption that the supply current will be changed by faults in the logic circuits. A generation mechanism of current variation is represented by an autoregressive model, and faults are detected by using pattern-recognition methods