Thermal-Aware Test Scheduling for Core-Based SoC in an Abort-on-First-Fail Test Environment

Long test application time and high temperature have become two major issues of system-on-chip (SoC) test. In order to minimize test application times and avoid overheating during tests, we propose a thermal-aware test scheduling technique for core-based SoC in an abort-on-first-fail (AOFF) test environment. The AOFF environment assumes that the test process is terminated as soon as the first fault is detected, which is usually deployed in volume production test. To avoid high temperature, test sets are partitioned into test sub-sequences which are separated by cooling periods. The proposed test scheduling technique utilizes instantaneous thermal simulation results to guide the partitioning of test sets and to determine the lengths of cooling periods. Experimental results have shown that the proposed technique is efficient to minimize the expected test application time while keeping the temperatures of cores under test below the imposed temperature limit

Test Scheduling for Modular SOCs in an Abort-on-Fail Environment – Web Site. http://www.ida.liu.se/ eslab/soctest/urban

Complex SOCs are increasingly tested in a modular fashion, which enables us to record the yield-per-module. In this paper, we consider the yield-per-module as the pass probability of the module’s manufacturing test. We use it to exploit the abort-on-fail feature of ATEs, in order to reduce the expected test application time. We present a model for expected test application time, which obtains increasing accuracy due to decreasing granularity of the abortable test unit. For a given SOC, with a modular test architecture consisting of wrappers and disjunct TAMs, and for given pass probabilities per module test, we schedule the tests on each TAM such that the expected test application time is minimized. We describe two heuristic scheduling approaches, one without and one with preemption. Experimental results for the ITC’02 SOC Test Benchmarks demonstrate the effectiveness of our approach, as we achieve up to 97 % reduction of the expected test application time, without any modification of the SOC or ATE.