Power conscious test synthesis and scheduling for BIST RTL data paths

Previous research has outlined that power dissipated during test application is substantially higher than during functional operation, which leads to loss of yield and decreases reliability. This paper shows for the first time how power is minimized in BIST RTL data paths by using power conscious test synthesis and test scheduling. According to the necessity for achieving the required test efficiency power dissipation is classified into necessary and useless power dissipation. According to the occurrence during the testing process power dissipation is classified into test application and shifting power dissipation. The effect of test synthesis and scheduling on power dissipation is analyzed and power minimization is achieved in two steps. Firstly, during the testable design space exploration only power conscious test synthesis moves are accepted leading to minimization of useless power dissipation. Secondly, module selection during power conscious test scheduling satisfies power constraints while reducing test application time. Experimental results using generic power models show savings up to 28% in test application power dissipation and up to 29% in shifting power dissipation.