Serial bus voltage compensation

A serial bus voltage control system, comprising:

• a voltage regulator configured to provide power to a plurality of serial buses;
• wherein each of the serial buses is configured to provide power from the voltage regulator to a device coupled to the serial bus and to serially transfer data between devices coupled to the serial bus;
• a plurality of power switches, each configured to switch power from the voltage regulator to one of the serial buses, each of the power switches comprising:
• a switch input terminal coupled to an output of the voltage regulator;
• and
• a switch output terminal coupled to one of the serial buses;
• a voltage control loop;
• and;
• a voltage monitor coupled to the voltage regulator and coupled to the output terminal of each of the power switches;
• wherein the voltage monitor is configured to adjust the output voltage of the voltage regulator based on a reference voltage provided from one of the switch output terminals;
• wherein the voltage control loop is configured to reduce the bus voltage at the output terminal of the power switch based on the adjusted output voltage of the voltage regulator causing the voltage at the output terminal to exceed an upper limit of a predetermined operational voltage range for the serial bus.

A serial bus power delivery system, comprising:

• a voltage regulator configured to provide power to a plurality of serial buses;
• wherein each of the serial buses is configured to provide power from the voltage regulator to a device coupled to the serial bus and to serially transfer data between devices coupled to the serial bus;
• a plurality of power switches, each configured to switch power from the voltage regulator to one of the serial buses, each of the power switches comprising:
• a switch input terminal coupled to an output of the voltage regulator;
• and
• a switch output terminal coupled to one of the serial buses, and;
• a voltage monitor coupled to the voltage regulator and coupled to the output terminal of each of the power switches, the voltage monitor comprising:
• a lowest voltage selector;
• and
• a lowest voltage limiter;
• wherein the lowest voltage selector is configured to:
• compare bus voltages at the output terminals of the power switches;
• identify a lowest of the bus voltages via the comparison;
• and
• apply the identified lowest of the bus voltages to adjust output voltage of the voltage regulator such that the identified lowest of the bus voltages is within a predetermined operational voltage range;
• and
• wherein the lowest voltage limiter is configured to determine whether the identified lowest of the bus voltages is too low to be applied to adjust the output voltage of the voltage regulator.