EDNE August 2012 - (Page 23)

To reduce a circuit’s EMI susceptibility, a board designer should pay attention to good layout practices by keeping traces short, using surface-mount components, and using a PCB with a dedicated ground plane for the signal returns. Keep the ground plane as complete as possible and keep the digital signals away from the analog-signal paths. Additionally, place RF-bypass capacitors on all of the IC’s power-supply pins, position these capacitors close to the device pins, and make sure their impedances are as close to 0Ω as possible at the potential EMI frequencies.EDN Bonnie Baker is a senior applications engineer at Texas Instruments and author of A Baker’s Dozen: Real Analog Solutions for Digital Designers. Read the first parts of this series; Figure 2 The OPA333 CMOS op amp can reject frequency signals greater than its 300-kHz bandwidth. www.edn-europe.com/article. asp?articleid=5477 2 www.edn-europe.com/article. asp?articleid=5508 3 www.edn-europe.com/article. asp?articleid=5547 4 www.edn-europe.com/article. asp?articleid=5608 1 Passive filter components suffer from nonidealities in parasitic capacitances and inductances, which limits the filter’s ability to suppress noise at high frequencies. In contrast, IC processes closely match electrical characteristics of the on-chip passive components. Finally, the IC, with the internal filter, also offers reduced parts count, cost, and board area. http://www.edn-europe.com/article.asp?articleid=5477 http://www.edn-europe.com/article.asp?articleid=5508 http://www.edn-europe.com/article.asp?articleid=5547 http://www.edn-europe.com/article.asp?articleid=5608 http://www.picotest.com/blog http://www.omicron-lab.com

Table of Contents for the Digital Edition of EDNE August 2012

Messe München
Messe München
Cover
Contents
Farnell
Microchip
Digi-key
Masthead
Comment
Pulse
Digi-key
Test & Measurement
Agilent Technologies
Understand the digital-output options for high-speed ADCs
Digi-key
Baker's best
Omicron
Cover Story
Digi-key
Generating spatial audio from portable products
Supply Chain
Design Idea
Product Roundup
Tales From The Cube

EDNE August 2012