There are a few applications where polymer should not be used which include Frequencies approaching or exceeding 1 MHz, Temperatures exceeding 150°C, Voltage rails exceeding 48 V, low ESR below 4 mΩ is required, reverse bias circuits, low capacitance below 0.68 µF is needed and in applications where high leakage, also known as DCL, is a concern such as when the part is connected to a battery. DCL capability is a recurrent question for Polymer. During the last few years, KEMET’s technology team has developed material settings to enhance the tantalum Pentoxide/PEDT interface and improve reliability. This feature will be added to the T52x – T530 catalogue and will exhibit 0.03 CV and 0.05 CV DCL. KEMET is starting with the 1st to market T521X476M035AT*030 with low DCL and 125ºC max operational temperature, with additional part numbers that will be added soon after.