10.2.1.2.6 Input Capacitor

For most applications, 10µF is sufficient and is recommended, though a larger value reduces input current ripple further. The input capacitor buffers the input voltage during transient events and also decouples the converter from the supply. A low ESR multilayer ceramic capacitor is recommended for best filtering and should be placed between PVIN and PGND as close as possible to those pins. Even though AVIN and PVIN must be supplied from the same input source, it's required to place a capacitance of 0.1uF from AVIN to AGND, to avoid potential noise coupling. An RC, low-pass filter from PVIN to AVIN may be used but is not required.