Are there specifications for input surge currents (inrush currents) with DC input power modules / on-board power supplies?
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A. There are regularly no stipulations in the specifications.
Please refer to the typical waveforms listed in the data for the models of the respective products.
Input surge currents (inrush currents) are charging currents that flow into capacitors that are connected between input lines when the power is turned on. These currents also flow when input voltage is instantly applied with a device such as a switch in DC input power modules / on-board products. However, the values of the input surge currents (inrush currents) change according to the capacity of input capacitors that are additionally connected outside or impedance components of wiring patterns.

Figure 1

Figure 1
*The input surge current (inrush current) is the total value of the charging current that flows into the capacitor inside the product ① and the charging current that flows into the input capacitor Cin that connects to the exterior ②.