The architecture of the TPS62A0x allows use of tiny ceramic-type output capacitors with low equivalent series resistance (ESR). These capacitors provide low output voltage ripple and are thus recommended. To keep its resistance up to high frequencies and to achieve narrow capacitance variation with temperature, it is recommended to use X7R or X5R dielectric.
The input capacitor is the low impedance energy source for the converter that helps provide stable operation. A low-ESR multilayer ceramic capacitor is recommended for best filtering. For most applications, a 4.7-μF input capacitor is sufficient; a larger value reduces input voltage ripple.
The TPS62A0x is designed to operate with an output capacitor of 10 μF to 47 μF, depending on the selected output voltage, as outlined in Table 9-3.
A feedforward capacitor reduces the output ripple in PSM and improves the load transient response. A 120-pF capacitor is good for the 1.8-V output typical application.