Method and system for load sharing in a multiple power supply system. At least some of the illustrative embodiments are power supply units including a switching circuit, a coarse adjustment circuit coupled to the switching circuit (the coarse adjustment circuit configured to send an internal command to the switching circuit to modify a pulse width modulated signal that controls output current of the power supply unit), and a communication port coupled to the switching circuit. The power supply unit configured to receive from an external device over the communication port an external command to modify the pulse width modulated signal of the switching circuit. The power supply unit is also configured to modify the output current, the amount of modification based on the external command, and the internal command from the coarse adjustment circuit.