AN4539 Datasheet, PDF (1/33 Pages) STMicroelectronics – HRTIM cookbook

AN4539
Application note
HRTIM cookbook
Introduction
Among STM32 microcontrollers, STM32F334xx products have been developed to address
market segments requiring digital signals with highly accurate timings, and especially digital
power conversion applications. Among them:
• digital power supplies;
• lighting;
• uninterruptible Power Supplies;
• solar inverters;
• wireless chargers.
The STM32F334xx microcontrollers feature an High Resolution Timer (HRTIM) peripheral
that can generate up to 10 signals and is able to handle a large variety of input signals for
control, synchronization or protection purposes. Its modular architecture allows to address
most of conversion topologies and multiple parallel converters, with the possibility to
reconfigure them during run-time.
At first glance, reading the STM32F334 reference manual, this peripheral may appear
complex, mostly because of the large control register set. To complement this extensive
description, we have prepared an additional document that includes quick-start informations
and a collection of examples.
In its first section, this cookbook aims to show that HRTIM programming is simple. The
environment (the kitchen...) setup is first explained, followed by a number of simple
examples given for understanding by practicing. These basic cases are provided to
introduce step by step the timer features and to provide programming guidelines. This
section should be read extensively by people not familiar with the HRTIM.
The second part is a collection of converter recipes to be used when starting a new design,
either to pick up a ready-made code example, or to get ideas and programming tricks when
dealing with a topology not described in this document. It shall be noted however that this
cookbook does not cover the converter design itself (control techniques and components
dimensioning) which may be described in dedicated application notes.
Each example is provided with a brief converter description when necessary (topology and
connections to the MCU), the control waveform(s) and a code snippet. These snippets (and
the equivalent code done based the STM32 HAL library) can be downloaded from
www.st.com.
Type
Microcontrollers
Table 1. Applicable products
Part numbers and product categories
STM32F334xx
June 2014
DocID026506 Rev 1
1/33
www.st.com