RE: gEDA-user: rs232 ferrite size?
I can't imagine why you would want one on either TX or RX... I have never had any issues with RS232 on any board I have designed. My biggest RS232 issue is usually finding a computer that has a serial port grumble stupid laptops and their serial port exclusion /grumble Joel Ostheller -Original Message- From: [EMAIL PROTECTED] [mailto:geda-user- [EMAIL PROTECTED] On Behalf Of DJ Delorie Sent: Sunday, January 21, 2007 7:59 PM To: geda-user@moria.seul.org Subject: gEDA-user: rs232 ferrite size? What's a good size ferrite to use on an rs232 line? I've got a spot for a set of 0603 ferrites on my serial console lines, but I have no idea what size (uH) ferrite to use. user ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
RE: gEDA-user: rs232 ferrite size?
On Mon, 2007-01-22 at 09:30 -0800, Ostheller, Joel A. wrote: I can't imagine why you would want one on either TX or RX... I have never had any issues with RS232 on any board I have designed. My biggest RS232 issue is usually finding a computer that has a serial port grumble stupid laptops and their serial port exclusion /grumble My HP Compaq nc6320 has a serial port - and parallel port! I think it is because its from their business range, rather than the shiny multimedia types you normally find in shops. It also has odd bios / acpi issues with linux - but we can't have everything, right? Peter C. ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
Re: gEDA-user: rs232 ferrite size?
One part we use a lot is a Murata BLM18AG102SN1. They are available from DigiKey. This part has a fairly high resistive component, chosen specifically for our use mainly as a power supply filter. It would also be appropriate for slower data signals like RS-232. If you were concerned about too much filtering at higher frequencies, they have other parts in this family with less of a resistive component. Thanks, that fits the bill. ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
Re: gEDA-user: rs232 ferrite size?
You worried about bad bits or overvoltage? An EMI ferrite isn't going to have much effect on either for a relatively high Z interface like RS-232. The serial port will only be rarely used, and the chip controlling it can be replaced. The lines that will be in continuous use have stronger ESD protection on them. The reference design had ferrites, so I'm using ferrites. ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
