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Emi design issues, Emc design tips – Echelon LonWorks Router User Manual

Page 99

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EMI Design Issues

The high-speed digital signals associated with microcontroller designs can

generate unintentional Electromagnetic Interference (EMI). High-speed voltage

changes generate RF currents that can cause radiation from a product with a

length of wire or piece of metal that can serve as an antenna.
Products that use the RTR-10 router will generally need to demonstrate

compliance with EMI limits enforced by various regulatory agencies. In the USA,

the FCC requires that unintentional radiators comply with Part 15 level “A” for

industrial products, and level “B” for products that can be used in residential

environments. Similar regulations are imposed in most countries throughout the

world. For more information about such regulations, see European EMC

standards, such as VDE 0871, Class “B” 1984, and CISPR Publications 22.
Echelon has designed the RTR-10 router with low enough RF noise levels for

design into level “B” products. Echelon encourages level “B” compliance for all

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compatible products.

Echelon has performed immunity tests for CE Marking on Series 5000 devices,

including the Router 5000 and FT Router 5000, and has also performed

additional tests to ensure immunity and low emissions. Specifically, Echelon has

performed the following immunity tests:

Electrostatic discharge (ESD) testing (both air and contact discharge) for

compliance with Comité Européen de Normalisation2 (CEN), standard

EN 61000-4-2

Radiated radio frequency (RF) immunity testing for compliance with

CEN standard EN 61000-4-3

Burst testing for compliance with CEN standard EN 61000-4-4

Surge testing for compliance with CEN standard EN 61000-4-5

Conducted RF Immunity testing for compliance with CEN standard EN

61000-4-6

You need to perform your own immunity testing for Series 5000 router devices

that you design and build. See the Series 5000 Chip Data Book for additional

information about electromagnetic compatibility (EMC) design guidelines for a

Series 5000 Chip, including the Router 5000 and FT Router 5000.

Designing Systems for EMC (Electromagnetic
Compatibility)

The RTR-10 router has been designed so that products using it should be able to

meet both FCC and VDE level “B” limits. Careful system design is important to

guarantee that an RTR-10 router-based product will achieve the desired EMC.

EMC Design Tips

The following general design tips can help ensure successful EMC for your RTR-

10 or Series 5000 router devices:

2

European Committee for Standardization

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Router User’s Guide

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