Power Management Bus (PMBus) Power Management Bus (PMBus) is a serial communications protocol aimed at the configuration, control, and monitoring of power supply devices. The System Management Interface Forum (SMIF) owns and maintains the standard. PMBus operates over an SMBus physical layer, which is a low-cost two-wire bus largely derived from I²C, providing additional control signals. The resultant protocol provides a comprehensive set of power supply management and fault reporting commands. A PMBus configuration consists of a single bus master and one or more slave power supply devices. The bus master may be a dedicated PMBus controller, microcontroller, FPGA, or an automated-test-equipment (ATE). A potential slave device may be an AC-DC or DC-DC power supply, Point-of-Load (PoL) converter, or a microprocessor power supply. More information on PMBus - Power Management Bus >>