Abstract: An in-rush current limiter and method is provided. The in-rush current limiter reduces the maximum current that is drawn during system startup of an avionics system. During startup, power is provided through a power supply bus to a plurality of avionics units that are each coupled to the power bus. To reduce the maximum current drawn by the avionics units during startup, the in-rush current limiter includes a current limiter controller, a charging circuit, and a switching circuit. Specifically, during system startup the main current path from the power supply bus is interrupted by the switching circuit while an alternate current path is connected through the charging circuit. During this charging the amount of current flowing through the charging circuit is limited to an acceptable level by a resistive element in the charging circuit.