The recommended input capacitance for MPS hot swap parts is 0.1uF - 1uF. This value provides appropriate limitations on inrush current and further guarantees protection from output and input transients on the device. Some MPS parts, i.e. MP5021B, do not require input capacitance because the chip is soldered on an unmated card which already provides minimal capacitance to the voltage bus. Though some datasheets will show substantial input capacitance on typical applications, this is mostly for EVB testing and this capacitance should not be present in actual designs.
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