You can find all sorts of different transformer configurations. The magnetics vendors have technical stuff that often knows what is good and in which application, yet they also sell what they know isn't technically very good. The reason is that oftentimes customers require a specific configuration, and if they want to get business they do what customers ask them.
If you need guidance in selecting a part from a magnetics company, ask to speak with their lead design enginieers, and only after that discuss it with the sales guys. Neven > The magnetics are made up of both a 1 to 1 isolation xformer and a cm choke. I > just stared at a schematic and I don't know if its an error, a single part or > generic, but for this one part the common mode choke was on the cable side for > the TX lines and on the IC side for the RX lines. I have never noticed that > before. I'll be looking at some other parts now that you have my interest > piqued. > Gary > -----Original Message----- > From: Muhammad Sagarwala [mailto:msa...@force10networks.com] > Sent: Monday, February 03, 2003 9:00 AM > To: emc-p...@majordomo.ieee.org > Subject: rj45 with integrated magnetics.. > > > > Here is a question for you Gurus.. > > I was looked at a few different rj45 with integrated magnetics. While all of > them were different in some respect, I found two major categories - one with > common mode choke on the chip (IC) side while others with common mode choke on > the cable side. My question would be "why would one want to use a connector > with common mode choke on the chip side vs connector with common mode choke on > the cable side??? I wanted to know specific scenario where a person would > prefer one over the other." > > Here I would like to add that most of the problems I have seen in my short > career are due to common mode noise making its way to the cable. > > Also, I would appreciate if someone could point me to a document where I could > find rules/factors to consider while selecting a jack with integrated magnetics > . > > Muhammad > > This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
