AN2511 Datasheet, PDF (1/43 Pages) STMicroelectronics – This application note describes

AN2511
Application note
PMBus^TM interface using ST7 I²C
Introduction
The PMBus^TM (power management bus) is an open standard protocol that defines a means
of communicating with power conversion and other devices. The PMBus protocol helps to
establish the first truly open communications standard for the digital control of power
systems. Implemented over the industry-standard SMBus (system management bus) serial
interface, the PMBus protocol facilitates the programming, control and real-time monitoring
of compliant power conversion products.
This application note describes how to use the ST7 I²C peripheral for PMBus
communication. The firmware of this application performs the PMBus bus protocols
mentioned in PMBusTM power system management protocol specification v1.0. The device
chosen here is ST72264G1 which has multi-master I²C capability. This microcontroller acts
as the PMBus master. It controls the PMBus compatible slaves. The firmware described in
this application note is in C language.
To show the PMBus capabilities of ST7, a dedicated demonstration board is developed. This
board consists of the ST72F264G1 microcontroller and it works with PC hyperterminal. The
objective of this demonstration board is to show to the user the features and capabilities of
PMBus features using ST7 I²C peripheral, to support the standard PMBus commands. The
results of this demonstration board interfaced with Artesyn's PMBus module are shown in
this application note.
August 2010
Doc ID 13286 Rev 2
1/43
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