Power Management Bus (PMBus) is a type of the System Management Bus (SMBus) which is designed for digital management of power supplies. Power Management Bus is a relatively slow speed two wire communications protocol based on I²C. PMBus works well for Battery management systems, AC-DC power inverters, Isolated DC-DC and bus converters, Non-isolated Point-of-Load (POL) converters, Microprocessor power converters. PMBus is NOT a standard for designing power supplies, but an efficient communication bus for power supply network.

Power Management Bus (PMBus) is an open standard power-management protocol with a fully defined command language that facilitates communication with power converters and other devices in a power system. The protocol is implemented over the industry-standard SMBus serial interface and enables programming, control, and real-time monitoring of compliant power conversion products.

Power Management Bus (PMBus) Advantages

  • Power Management Bus (PMBus) is a flexible and highly versatile standard for digital power system management.
  • PMBus supports communication between devices based on both analog and digital technologies, embedded, discrete convereters.
  • PMBus provides true interoperability which will reduce design complexity and shorten time to market for power system designers.
  • PMBus is a low cost power management and communication protocol like I2C. PMBus has more features, and robust than I2C.

Power Management Bus (PMBus) Specifications

Part-1 of PMBus specifications define the transportation part which discusses Addressing of PMBus devices, and Hardware signals such as control signals. Part-2 of PMBus specifications define the command language used for PMBus configuration, control, status monitoring, fault management, and information storage.

Power Management Bus (PMBus) Specifications for PMBus 1.0, 1.1 can be downloaded from http://pmbus.org/specs.html, and the latest revision PMBus 1.2 can be availed upon email request to webmaster@SMIForum.org.