With the increasing market demand seen for low-voltage digital applications, tantalum electrolytic capacitors are becoming the first choice to replace MLCC (multi-layer ceramic) technologies. The range of tantalum, polymer, and niobium oxide options available from AVX makes it easier to convert from MLCC, due to the overlap in capacitance ratings and footprint sizes.
There are three main advantages that tantalum capacitors have over MLCCs.
1. Voltage Coefficient. The capacitance of a MLCC will decrease as bias voltage increases. Tantalum, polymer, and niobium oxide capacitors don’t exhibit this voltage coefficient effect.
2. Temperature Coefficient. The capacitance of a MLCC decreases at both high and low temperatures, however, tantalum capacitors don’t show this effect, either.
3. Equivalent Series Resistance. The impedance curve of a MLCC has sharp resonance and very low ESR. With a tantalum capacitor, though, the impedance curve is more broadband. The ESR of tantalum capacitors is also low, especially at low temperatures.
These three performance advantages, coupled with easy substitution from MLCCs, make tantalum capacitors a viable choice for use in your next project.