Part # Application Note General Purpose Products 8-Bit Microcontrollers AN901 datasheet

Part Manufacturer: ST Microelectronics

ST Microelectronics

Part Description: EMC guidelines for microcontroller-based applications

Part Details:

AN901 APPLICATION NOTE EMC GUIDELINES FOR MICROCONTROLLER-BASED APPLICATIONS by Microcontroller Division Applications INTRODUCTION Electromagnetic compatibility (EMC) must be taken into account at the very beginning of aproject as the cost of correcting an EMC problem encountered at the start of production can befar greater that the cost of a detailed EMC study during the development phase of an applica-tion. The use of microcontroller-based systems is increasingly wide-spread, especially in suchareas as consumer, industrial and automotive applications, where the drive for cost reductionis the common trend. This emphasis on cost reduction and the increasing complexity of suchsystems requires the manufacturers of semiconductor components to develop highly inte-grated, single chip, high operating frequency microcontrollers using the highest density tech-nology possible. Unfortunately, for semiconductor structures, the higher the density and thefaster the operation, intrinsically the higher the level of electrical noise generated, and the in- creased sensitivity to spikes induced from external noise. Therefore, the PCB layout, the soft-ware and the system must now apply EMC "hardening" techniques in their design. This note aims to provide guidelines for designers of microcontroller-based applications sothat the optimum level of EMC performances can be achieved. For general information about EMC performances, please refer to application note AN898. AN901/1100 1/14 1 EMC GUIDELINES FOR MICROCONTROLLER-BASED APPLICATIONS 1 DEFINITION OF TERMS Electromagnetic compatibility (EMC) is the capacity of a piece of equipment to work properlyin its normal environment, and not create electrical disturbances that would interfere with otherequipment. Electromagnetic susceptibility (EMS) is the level of resistance to electrical disturbances suchas electromagnetic fields and conducted electrical noise. Electromagnetic interference (EMI) is the level of conducted/radiated electrical noise createdby the equipment. There exists several standards addressing EMS or EMI issues, and for every type of applica-tion area. These standards apply to finished equipment. Up to now, there is no officialstandard applicable to sub-systems or electronic components. Nevertheless, EMC tests must be performed on the sub-systems in order to evaluate and optimize applications for EMC per-formances. 1.1 EMC STANDARDS Table 1. Electromagnetic Emissions EQUIVALENT STANDARD DESCRIPTION INTERNATIONAL STANDARD EN50081-1 Generic emissions standards - Residential EN50081-2 Generic emissions standards - Industrial EN55011 CISPR 11 For industrial, scientific and medical equipment EN55013 CISPR 13 For broadcast receivers EN 55014 CISPR 14 For household appliances/tools EN 55022 CISPR 22 For data processing equipment SAE 1752/3 American Measurements Procedure for susceptibility Table 2. Electromagnetic Susceptibility EQUIVALENT STANDARD DESCRIPTION INTERNATIONAL STANDARD EN50082-1 Generic immunity standards - Residential EN50082-2 Generic immunity standards - Industrial

Please click the following link to download the datasheet:

Application Note General Purpose Products 8-Bit Microcontrollers AN901.pdf Datasheet