SWT Silver Cased Subminiature


These commercial wet-slug tantalum capacitors are subminiature in size and have outstanding performance with the following characteristics:

  • Highest capacitance per unit weight
  • Highest capacitance per unit volume
  • Ten case sizes for maximum volumetric efficiency
  • Lowest leakage current of any type of electrolytic capacitor


1. Operating Temperature Range: SWT Capacitors are designed to operate without voltage derating over a temperature range of -55° to +85°C.

2. D.C. Rated Voltage: The maximum allowable continuous D.C. voltage at the rated temperature of 85° C. Reverse voltage should never be used with wet slug tantalum capacitors.

3. Capacitance and Dissipation Factor: The capacitance and dissipation factor shall be measured at 120Hz and 25°C and be within the specified tolerance limits. Capacitance and D.F. shall be measured on a polarized capacitance bridge. The D.C. bias voltage shall be between 1.2 and 2.2 volts. The A.C. voltage shall be .5V RMS maximum.

The Dissipation Factor Limits are as Follows:

Case SizeRated Voltage

3A, 3B18161413121010
4B, 4C21201816161313
5A, 5B, 5C35262118171513


4. D.C. Leakage Current: The D.C. leakage current shall be measured after 5 minutes (except 10 minutes for 5C and 6C cases) application of rated voltage at 25°C to the capacitor in series with a 1000 ohm resistor. A regulated power supply or batteries should be used as a voltage source. The leakage shall not exceed the maximum specified values. The D.C. leakage current at 25°C shall be 2.0 microamps maximum through 5C case. 6C case D.C. leakage at 25°C shall be 4.0 microamps. At 85° C the D.C. leakage shall not exceed the following limits:

Case SizeMaximum D.C.L.
3A, 3B6.0 microamps
3C7.0 microamps
4B, 4C, 5A8.0 microamps
5B, 5C, 6C10.0 microamps

15.0 microamps

5. Surge Voltage: The surge voltage is the maximum intermittent D.C. voltage which should be applied to the capacitor under any conditions. Transient and peak ripple voltage must be included. The surge voltage of SWT capacitors is 115% of the D.C. rated voltage.

The capacitors shall withstand 1000 cycles of surge voltage applied at 85°C through a 1000 ohm resistor. Each cycle shall consist of 1/2 minute on voltage and 51/2 minutes with no voltage applied. After the test the capacitor will meet the initial 25°C electrical requirements.

6. Life Test: Life test shall be carried out by the application on rated voltage for 1000 hours at 85° C. At the conclusion of the period the capacitance shall not have changed more than ±15% from the initial value (+15% -20% for 6V and 10V parts). The DC leakage current will meet the initial limits and the D.F. will not exceed 1.5 times the initial limit.

7. Capacitance Tolerance: The standard tolerances are -15% to +75% (U), ±20% (M), ±10% (K), ±15% (J).

8. Lead Pull: The leads shall withstand a 3 pound axial pull for 5 seconds.

9. Lead Bend: At the point of egress from the capacitor, the leads shall withstand three 90° bends around a radius equal to the lead diameter.

10. Marking: Capacitor polarity is indicated by the red epoxy end and by a + sign. The EIA date code, capacitance, voltage and tolerance are also printed on the case