Controlling Peak Power Consumption for Scan Based Multiple Weighted Random BIST

This paper presents a multiple weight set weighted random BIST scheme to perform power aware test which takes into account peak power constraint while reducing the overall energy consumption. Generally, exceeding the peak power budget during test provokes problems such as erroneous circuit function due to IR drop and electrical damage to the circuit. On the other hand, excessive power reduction during test can degrade fault screening capability of the test since the test environment becomes substantially less stringent than the environment in which the device is actually used. In this paper we address both these problem simultaneously. The main contribution of this paper is to provide an efficient scan based weighted random BIST scheme within peak power constraint and adequate energy consumption. In order to restrict the amount of test power consumption, fault clustering is performed. The size of the fault cluster is changed to adjust the amount of power consumption. We assume full scan environment, test per scan testing, and single stuck-at fault model. Genetic algorithm (GA) based optimization method is proposed to find effective weight sets.