Progressive stress test

The stress in Progressive stress test rises with time, which can quickly excite the failure of the devices, so as to further improve the efficiency of the accelerated life test(LED Life Test). But because it is difficult to accurately control the external stress, it is easy to cause the change of the failure mechanism in the process of the test, it is not commonly used.

The LED devices are mostly drived by current, and they are affected by temperature significantly, so it is often to choose current and temperature as the stress. The accelerated test is the effective means for the reliability analysis, but it must ensure that the failure mechanism of the devices would not change in the whole test.