A self-testing ALU using built-in current sensing

Abstract

A CMOS ALU (arithmetic logic unit) chip containing built-in current (BIC) sensors, which perform self-testing of the ALU, is described. The performance of two ALUs (one with and one without a BIC sensor) is analyzed by using externally applied test vectors and linear feedback shift register for BIC and for stuck-fault testing. The results demonstrate that the BIC testing methodology is well suited for initial die testing of CMOS ICs as well as for concurrent self-testing of highly reliable systems