To comprehensively evaluate the long-term reliability of tunneling magnetoresistance (TMR) current sensors under harsh environments
a multi-stress accelerated testing methodology was established. The test matrix includes high- and low-temperature storage
damp-heat aging
thermal cycling
and electromagnetic disturbance tests
while key performance drifts and physical failure mechanisms are continuously monitored. The results show that the absolute sensitivity drift is ≤5% after 1 000 h storage at 150 ℃
and the absolute zero-offset drift is ≤3% with no progressive degradation after 1 000 h biased aging at 85 ℃ and 85% relative humidity (RH). No functional failures are observed during thermal cycling (-40 ℃ ↔ 125 ℃) or under electrical fast transient (EFT) and surge stresses. Based on multi-stress lifetime modeling
the lifetime is projected to be decades under typical ambient conditions by translating accelerated-test results to nominal use conditions
meeting long-term reliability requirements for power equipment. Dominant failure modes include material aging at high temperatures
corrosion induced by package degradation in humid environments
and transient dielectric breakdown during lightning surges. This study provides a scientific basis for TMR sensor lifetime assessment and high-reliability design.