The ceramic input capacitors provide a low impedance source to the regulator in addition to supplying ripple current and isolating switching noise from other circuits. Table 5 shows the nominal and minimum values of total input capacitance recommenced for the LM53625/35-Q1. Also shown are the measured values of effective capacitance for the indicated capacitor. In addition, small high frequency bypass capacitors connected directly between the VIN and PGND pins are very helpful in reducing noise spikes and aid in reducing conducted EMI. TI recommends that a small case size 10-nF ceramic capacitor be placed across the input, as close to the device as possible. Additional high-frequency capacitors can be used to help manage conducted EMI or voltage spike issues that may be encountered.