PCB decoupling capacitor performance for optimum EMC design by Archambeault B.

By Archambeault B.

The optimal layout of decoupling capacitors on a published circuit (PC) board has been the topic of dialogue and opinion for a few years. reason and impression were tricky to split from the entire different results occuring on a standard energetic notebook board. Tins paintings used a particularly designed laptop board to permit the measruement and characterization of the results of varied decoupling capacitor strageties. Many universal reviews and myths are investigated, and the optimal layout stragety instructed dependent upon the measured info during this document.

Show description

Read or Download PCB decoupling capacitor performance for optimum EMC design PDF

Best electronics: radio books

ADSL,VDSL and multicarrier modulation

The state-of-the-art of multicarrier modulation for the transmission of high-speed facts With DSL know-how poised to supply the quickest technique of web entry for future years, there's a becoming desire for sensible info on operating xDSL companies over latest cellphone strains. Communications professional John Bingham attracts on 3 many years of intimate involvement with information transmission examine to supply a whole consultant to the state-of-the-art and destiny path of multicarrier modulation (MCM)-one of the major equipment for high-speed information transmission this present day.

3D Integration for NoC-based SoC Architectures

Again conceal reproduction sequence: built-in Circuits and structures 3D-Integration for NoC-based SoC Architectures via: (Editors) Abbas Sheibanyrad Frédéric Petrot Axel Janstch This ebook investigates at the provides, demanding situations, and suggestions for the 3D Integration (vertically stacking) of embedded platforms attached through a community on a chip.

Radioactive Waste Management 2000: Challenges, Solutions and Opportunities (Imeche Event Publications)

The papers during this quantity were written and taken jointly via a bunch of specialists, every one of whom offers with radioactive waste administration each day, in addition to having the deep wisdom and point of craftsmanship that purely insiders can in achieving. themes lined the following comprise: remedy matters; waste mangement perform; shipping and garage; and setting and rules.

Additional info for PCB decoupling capacitor performance for optimum EMC design

Sample text

01 uF) make a significant improvement in the S21 at frequencies below about 200 MHz, but make only a little change at higher frequencies. This is mostly due to the self resonance of the capacitor, and the inductive nature of the capacitor above its natural resonant frequency. Therefore, high frequency capacitors should also be distributed across the board. The value of these capacitors will determine the frequency range over which they are effective. The majority of emissions from a two-plane structure is along the edge of the board.

The main conclusion is that decoupling capacitors should be distributed across the entire board to help reduce the board resonances. These board resonances are the main decoupling problem at high frequencies (above about 20 MHz). The actual resonant frequency will change as the number, or location, or value of decoupling capacitors is changed. Predicting the exact resonant frequencies is impossible (given the number of variables), and so it must be expected that any harmonic noise will be at a frequency where a resonance occurs (worst case).

The majority of emissions from a two-plane structure is along the edge of the board. Care should be taken to ensure that no large openings in the shielded enclosure exist near the edge of the board. The testing of these various configurations is very time consuming. Now that a good base of test data is available, this data should be used to validate a modeling technique, and then the models used to simulate the performance of various other decoupling configurations. One potential configuration that shows promise is to combine the resistor-capacitor edge termination with ‘regular’distributed decoupling capacitors.

Download PDF sample

Rated 4.10 of 5 – based on 42 votes