The device is designed to operate from an input voltage supply range from 2.7 to 5.5 V. A 0.22-μF ceramic bypass capacitor is needed between IN and GND; TI recommends placing the capacitor close to the device. The output capacitor should be chosen based on the size of the load during the transition of the switch. TI recommends a 220-μF capacitor for 100-mA loads. Adding a 1-μF ceramic bypass capacitor at the output can help to improve the immunity of the device to short-circuit transients.

TPS2105-EP requires a high-quality ceramic, type X5R or X7R, input decoupling capacitor. The value of a ceramic capacitor varies significantly over temperature and the amount of DC bias applied to the capacitor. The capacitance variations due to temperature can be minimized by selecting a dielectric material that is stable over temperature. X5R and X7R ceramic dielectrics are usually selected for power regulator capacitors because they have a high capacitance to volume ratio and are fairly stable over temperature. The output capacitor must also be selected with the DC bias taken into account. Ceramic capacitors lose capacitance when a DC bias is applied across the capacitor. This capacitance loss is due to the polarization of the ceramic material. The capacitance loss is not permanent; after a large DC bias is applied, reducing the DC bias reduces the degree of polarization and capacitance increases. The capacitance value of a capacitor decreases as the DC bias across a capacitor increases.

All tantalum capacitors have tantalum (Ta) particles sintered together to form an anode. The cathode material can either be the traditional MnO₂ or a conductive polymer. Because MnO₂ is actually a semiconductor, it has a very high amount of resistance associated with it. A characteristic of this material is that as temperature changes, so does its conductivity. So MnO₂-based Tantalum capacitors have relatively high ESR and that ESR shifts significantly across the operational temperature range.

However, polymer-based cathodes use a highly-conductive polymer material. Because the material is inherently conductive, tantalum-polymers have a relatively-low ESR compared to their MnO₂ counterparts in the same voltage and capacitance ranges.

All tantalum capacitors have a voltage derating factor associated with them. Because the polymer material puts less stress on the tantalum-pentoxide dielectric during reflow soldering, more voltage can be applied compared to a MnO₂-based tantalum. For polymer-based capacitors, TI recommends 20% derating. Whereas the MnO₂-based tantalum capacitors require 50% or higher derating. Refer to the capacitor vendor data sheet for more details regarding the derating guidelines.