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SMD tantalum capacitors have the same problem as electrolytic capacitors when they are not used for a long time, months and years without use, they present failures, high current leakage, loss of capacitance and other problems related to disuse?

SMD tantalum capacitors do not suffer from the same "drying out" failure mode as wet aluminum electrolytics, but they are susceptible to damage from long-term disuse (years) due to dielectric breakdown. While not drying out, they can experience high leakage current or, more commonly, fail catastrophically by shorting out upon power-up due to a degradation of the dielectric layer.

Key Considerations for Tantalum Capacitors and Disuse:

Failure Mode: Unlike wet electrolytic capacitors that lose capacitance, tantalum capacitors often fail as a short circuit.

Dielectric Issues: Prolonged, unpowered storage can lead to a reduction in the insulation resistance of the tantalum pentoxide dielectric layer, causing high leakage current.

Reforming (Storage): While not as strictly required as with wet electrolytics, applying voltage to long-stored tantalum capacitors should be done cautiously, as they are sensitive to voltage spikes or reverse polarity, which can cause immediate failure.

Long-Term Stability: Generally, tantalum capacitors are more stable and have a longer shelf life than wet electrolytic capacitors, but they are not immune to issues after years of being unpowered.

For equipment left unused for years, it is safer to assume that any electrolytic capacitor—including tantalum—might have issues.