Sorry - no. The USB spec is available on the web & it tells you what is supposed to be going on in the finest of detail. (But it's also quite hard to understand) http://www.beyondlogic.org/usbnutshell/usb-in-a-nutshell.pdf gives a more readable overview of how it's all supposed to work complete with diagrams I think. Richard P On 28/06/06, Joe Mailer wrote: > BTW, do you have a schematic or similar ? To have an idea... > > Richard Prosser escribi=F3: Joe, > I think you'll need more than a transformer for USB. > IIRC the USB is mostly differential mode - but special codes are > signalled by common mode signals. In addition, the initial hanshake is > carried out at full (or low) speed with the D+ (or D-) line pulled > high with a 1k5 resistor. For high speed, this resistor has to be > disconnected. > > Richard P > > On 28/06/06, Joe Mailer wrote: > > Very interesting couplers. > > But these go up to 150 Mbps transfer rate. What about isolating a usb2.= 0 line at 480 Mbps ? I might have to do so with a small 1:1 transformer, an= y good reference ? > > > > Thanks ! > > > > William Bross escribi=F3: So does the si844x series couplers from http= ://www.silabs.com > > > > Bill > > > > Joe Mailer wrote: > > > > >iCouplers from analog claim to be bidirectional. > > > > > >Steve Smith escribi=F3: A transformer is naturally bidirectional you = need two optos > > >Just a thought ! > > >Steve > > > > > >-----Original Message----- > > >From: piclist-bounces@mit.edu [mailto:piclist-bounces@mit.edu] On Beha= lf Of > > >Joe Mailer > > >Sent: 21 June 2006 18:27 > > >To: Microcontroller discussion list - Public. > > >Subject: [EE] A<--> Optoisolators (comm) <--> B > > > > > >Hello, > > > > > >I have two systems A and B. I'd like to have a robust optically isolat= ed > > >communication line (going real time). I have choose RS-232/422/485 as > > >possible communication protocols. > > > > > >I have been searching the net for optoisolators, there are a huge amou= nt of > > >those, but thinking that communication is bidirectional and it could be > > >fast, what are more suitable optoisolators for doing such a thing ? I = have > > >been looking to (new) analog iCouplers[1], those look good, but i need= good > > >MTBF and good support in the future. > > > > > >Any other good idea ? > > > > > >Thanks ! > > > > > >[1] > > >http://www.analog.com/UploadedFiles/Product_Highlights/619913805627963= 397963 > > >229iCoupler_Brochure.pdf > > > > > > > > > > > > > > > > -- > > http://www.piclist.com PIC/SX FAQ & list archive > > View/change your membership options at > > http://mailman.mit.edu/mailman/listinfo/piclist > > > > > > > > --------------------------------- > > > > LLama Gratis a cualquier PC del Mundo. > > Llamadas a fijos y m=F3viles desde 1 c=E9ntimo por minuto. > > http://es.voice.yahoo.com > > -- > > http://www.piclist.com PIC/SX FAQ & list archive > > View/change your membership options at > > http://mailman.mit.edu/mailman/listinfo/piclist > > > > -- > http://www.piclist.com PIC/SX FAQ & list archive > View/change your membership options at > http://mailman.mit.edu/mailman/listinfo/piclist > > > > --------------------------------- > > LLama Gratis a cualquier PC del Mundo. > Llamadas a fijos y m=F3viles desde 1 c=E9ntimo por minuto. > http://es.voice.yahoo.com > -- > http://www.piclist.com PIC/SX FAQ & list archive > View/change your membership options at > http://mailman.mit.edu/mailman/listinfo/piclist > -- = http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist