MSPM0 PMBus Library User’s Guide

1. Introduction

The MSPM0 PMBus Library is based on the MSPM0 SMBus library. The MSPM0 PMBus library provides a set of APIs to communicate over PMBus as a controller or a target.

2. PMBus Library Supported Features

This library was developed in compliance with the PMBus 1.3.1 specification.

2.1 PMBus Supported Features

  • Address, memory, communication and capability related commands

  • On, off, and margin testing related commands

  • Output voltage related commands

  • “Other commands” as detailed by the PMBus specification

  • Fault related commands

  • Power good signal limits

  • Output voltage sequencing commands

  • Unit status commands

  • Parametric information commands

  • Manufacturer’s information commands

2.3 PMBus Features Not Currently Implemented

The PMBus features listed below are supported in hardware but have not been implemented in this release:

  • ZONE_READ and ZONE_WRITE protocols

3. PMBus Example Usage

This software library contains an example that demonstrate communication between a PMBus Controller and the TPS544B20EVM-634 evaluation module. The example configures the TPS544B20EVM-634’s behavior during under-voltage or over current events.

  • pmbus_controller_tps544b20evm

The above example contains source code which can be compiled and loaded onto a supported device as-is. Connect SMBCLK and SMBDAT between the controller and the TPS544B20EVM-634. Ensure properly sized pullup resistors are provisioned.

3.1 PMBus Examples Supported Hardware

  • 2 LP-MSPM0L1306 or LP-MSPM0G3507 LaunchPad evaluation boards