9.2.1.2.3 Output Capacitor Selection

TI recommends a minimum output capacitance (including DC bias effects) of 16 µF. Two 22-µF, 10-V ceramic capacitors are suitable for typical applications with V_O ≤ 3.6 V. For V_O > 3.6 V, three 22-µF or two 47-µF ceramic capacitors are suitable. If you want to minimize switching noise on the output, connect a small ceramic capacitor (100 nF is a typical value) in parallel to the two main output capacitors and place it closest to the VOUT pin. Smaller capacitors have lower parasitic inductance and are more effective at filtering high frequencies than the two main output capacitors.

The output capacitance does not have an upper limit, however, very large values of output capacitance make the transient response of the converter slower.

It is important that the effective capacitance is given according to the recommended value in Recommended Operating Conditions. In general, consider DC bias effects resulting in less effective capacitance. The choice of the output capacitance is mainly a trade-off between size and transient behavior as higher capacitance reduces transient response overshoot and undershoot and increases transient response time. Table 9 lists possible output capacitors.