July 2009

Doc ID 15468 Rev 1

1/18

AN2945

Application note

STM8S and STM32™ MCUs: a consistent 8/32-bit product line

for painless migration

Introduction

Following the market launch of the award winning STM32™ microcontroller,

STMicroelectronics completes the renewal of its microcontroller product line with the

announcement of the STM8S family. Significant effort has been made to rationalize the

MCU portfolio, in particular by capitalizing on common peripherals and software tools with

the aim to easing product migration.

The cost, in terms of both time and money, of maintaining a development team to design in

a new MCU family is a major criterion when selecting a microcontroller supplier. It is

therefore an advantage to make this kind of non-recurring investment if it applies to a broad

range of MCUs. With an MCU product line ranging from 20 to 144 pins, and memory sizes

from 2 to 512 Kbytes, the 8-bit STM8S and 32-bit STM32 families bring a lot of flexibility

when building a product portfolio. Should an 8-bit application run out of MIPS, there is an

upgrade path to the STM32 family. Conversely, if you wish to cut costs on a 32-bit platform,

it is relatively simple to switch to the STM8 family.

This document presents the similarities and common features of the STM8S and STM32

product lines, with a view of helping migration from one family to the other.

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