T22 Series Surface-Mount Wet Tantalum Capacitor

Vishay Sprague's T22 series true surface-mount (SMD) wet tantalum capacitor is suitable for space operations. Wet tantalum capacitors have been used extensively in military and high-reliability applications due to their long and stable life expectancy, high operating temperature range (greater than +200ºC), high voltage capability (up to 125 V), and high capacitance values. But until recently, they have not been available in SMD packaging. While solid tantalum capacitors have long been available in SMD versions, solving the problem of a hermetically sealed, wet electrolyte capacitor that can withstand the rigors of SMD temperatures has been challenging.

Vishay Sprague has provided a solution for this challenge with its T22 series of wet tantalum capacitors, and a third-party test has confirmed their suitability for space applications. Specifically, the T22 was tested by Dr. Alexander Teverovsky of NASA for hermeticity, the capability of withstanding high internal gas pressure, highly accelerated life testing (HALT) at +125°C and rated voltage, random vibration tests (RVT), and high-temperature storage (2500 hours) at +150°C. In addition, the parts were mounted to printed wire boards (PWB) where they were subjected to 1000 temperature cycles from -55°C to +125°C and additional HALT testing. The T22 was found to be suitable for space-level use. A description of the testing can be found here: Evaluation of Series T22 Wet Tantalum Capacitors.