Resistor – the basic failure model
Resistor common failure mode:
Resistors due to the structure is relatively simple, mature technology, the failure rate is usually relatively low. Failure of the main performance of the following:
- Resistance drift: usually occurs after aging; (screening by aging test to avoid the problem)
- Open circuit: may lead to open circuit when subjected to instantaneous power impact; (Transient power control resistor)
- Burned: a long time at a fixed power may occur when burning or even burned, usually open (control the steady-state resistance of resistance)
- Open wire breakage: wirewound resistors may occur when subjected to mechanical stress or transient overpower impact;
- Pin break: resistor pin can not be repeated bending;
6 welding problems: ultra-storage period, the lead oxide, poor coating, lead to serious asymmetry may lead to Weld and other welding problems.
- Vulcanization: This electrode is usually silver-palladium alloy. Due to the resistance of the surface of the secondary protective layer and the welding tip is not a perfect match. The surface electrode is partially exposed to the air. Therefore, when the air contains a large amount of sulfide gas, the silver is reacted with sulfide to form silver sulfide. Since silver sulfide is not conductive, the resistance gradually increases as the resistor is cured until it finally becomes an open circuit.