ST STM32F20 Series User Manual

August 2011 Doc ID 18267 Rev 2 1/29
AN3320
Application note
Getting started with STM32F20xxx/21xxx MCU
hardware development
Introduction
This application note is intended for system designers who require a hardware
implementation overview of the development board features such as the power supply, the
clock management, the reset control, the boot mode settings and the debug management. It
shows how to use the high-density performance line STM32F20xxx/21xxx product families
and describes the minimum hardware resources required to develop an
STM32F20xxx/21xxx application.
Detailed reference design schematics are also contained in this document with descriptions
of the main components, interfaces and modes.
www.st.com

ST STM32F20 Series Specifications

General

Brand	ST
Model	STM32F20 Series
Category	Microcontrollers
Language	English

Summary

Power Supplies

Voltage Regulator Operation

Explains the embedded voltage regulator and its operating modes.

Power Supply Schemes and Decoupling

Describes recommended external power supply connections and decoupling.

Reset and Power Supply Supervision

Power-On/Power-Down Reset (POR/PDR)

Details the integrated POR/PDR circuitry and its operation.

Programmable Voltage Detector (PVD)

Explains the PVD for monitoring VDD supply and generating interrupts.

System Reset Sources

Clock Management

HSE Oscillator Clock

LSE Oscillator Clock

Clock Security System (CSS)

Explains the CSS for detecting HSE oscillator failures.

Boot Configuration

Boot Mode Selection Methods

How to select boot modes using BOOT pins.

Boot Pin External Connections

Embedded Boot Loader Mode

Describes the embedded boot loader for Flash memory reprogramming.

Debug Management

SWJ Debug Port (Serial Wire & JTAG)

Explains the integrated SWJ-DP port combining JTAG and SW modes.

Debug Port Pinout and Availability

SWJ Debug Port Pin Configuration

Identifies the specific pins used for SWJ-DP functionality.

Flexible SWJ-DP Pin Assignment

JTAG Pin Pull-up/Pull-down Resistors

SWJ Debug Port to JTAG Connector

Shows the pin connections for SWJ-DP to a standard JTAG connector.

Design Recommendations

Printed Circuit Board Design

Ground and Power Supply Layout

Decoupling Capacitor Strategy

Recommendations for decoupling capacitors for power supply stability.

Reference Design

Reference Design Overview

Reference Design Component List

Lists mandatory and optional components for the reference design.