A power supply module for a power distribution cabinet that distributes power from one or more power sources to a plurality of internal cabinet modules, the power supply module including: a plurality of input terminals , each input terminal is configured to be connected to a different power source, wherein availability of each of the plurality of power sources varies during operation of a vehicle; a plurality of output terminals ; the power supply module characterized by a first output terminal being connected to receive power only from a first one of the plurality of input terminals ; and wherein a second one of the plurality of output terminals is connected to receive power only from a second one of the plurality of input terminals or a third one of the plurality of input terminals ; and wherein a third one of the plurality of output terminals is connected to receive power only from either the first one of the plurality of input terminals , the second one of the plurality of input terminals , or the third one of the plurality of input terminals , and further including: a switching up/down converter that is connected to receive power from either the first input terminal , the second input terminal , or the third input terminal , and is configured to provide hold-up power to the first output terminal , the second output terminal , and the third output terminal , and wherein the second output terminal is connected to each of the first input terminal , the second input terminal , and the third input terminal to form a first diode OR circuit and the third output terminal is connected to each of the second input terminal and the third input terminal to form a second diode OR circuit. a plurality of input terminals , each input terminal is configured to be connected to a different power source, wherein availability of each of the plurality of power sources varies during operation of a vehicle; a plurality of output terminals ; the power supply module characterized by a first output terminal being connected to receive power only from a first one of the plurality of input terminals ; and wherein a second one of the plurality of output terminals is connected to receive power only from a second one of the plurality of input terminals or a third one of the plurality of input terminals ; and wherein a third one of the plurality of output terminals is connected to receive power only from either the first one of the plurality of input terminals , the second one of the plurality of input terminals , or the third one of the plurality of input terminals , and further including: a switching up/down converter that is connected to receive power from either the first input terminal , the second input terminal , or the third input terminal , and is configured to provide hold-up power to the first output terminal , the second output terminal , and the third output terminal , and wherein the second output terminal is connected to each of the first input terminal , the second input terminal , and the third input terminal to form a first diode OR circuit and the third output terminal is connected to each of the second input terminal and the third input terminal to form a second diode OR circuit. <EOS>