Low ESR tantalums improve capacitance retention at high frequencies and low temperatures

Featuring a Ta anode and Ta2O5 dielectric, Kemet's T551 Series PHS (polymer hermetic seal) tantalum capacitors are now available from Mouser. A conductive organic polymer replaces the traditionally used MnO2 or wet electrolyte as the cathode plate of the capacitor. This results in very low ESR and improved capacitance retention at high frequency and low temperature. The T551 Series PHS also exhibits a benign failure mode, which eliminates the case breach that can occur in wet tantalum types. The device may be operated at voltages up to 80% of rated voltage with equivalent or better reliability than traditional MnO2 or wet tantalum capacitors operated at 50% of rated voltage. The series also offers higher ripple current handling capability and a lower ESR range than wet tantalums. T551 Series PHS provides the highest total capacitance and the most economical solution for high power applications, all within an approximately 25% lighter package than the equivalent wet tantalum capacitor, says the company. Applications include high-voltage power management, buck boost converters, filtering, hold-up capacitors and other high ripple current applications.