Post by thread:[BUY]: multiplexers

Hi everyone, I am looking for a smart analog multiplexer 4 to 1 or a smart switch. If anyone knows where I can find this part, please let me know. Thank you for your time.. _________________________________________________________________________ Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com. -- http://www.piclist.com hint: To leave the PICList spam_OUTpiclist-unsubscribe-requestTakeThisOuTmitvma.mit.edu

Sounds like a 4066 might be a candidate. -- Mitch -----Original Message----- From: pic microcontroller discussion list [.....PICLISTKILLspam@spam@MITVMA.MIT.EDU]On Behalf Of Tweedy Bird Sent: Tuesday, January 16, 2001 9:15 PM To: PICLISTKILLspamMITVMA.MIT.EDU Subject: [BUY]: multiplexers Hi everyone, I am looking for a smart analog multiplexer 4 to 1 or a smart switch. If anyone knows where I can find this part, please let me know. Thank you for your time.. _________________________________________________________________________ Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com. -- http://www.piclist.com hint: To leave the PICList .....piclist-unsubscribe-requestKILLspam.....mitvma.mit.edu -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads

Tweedy Bird wrote: >I am looking for a smart analog multiplexer 4 to 1 or a smart switch. If >anyone knows where I can find this part, please let me know. > What on earth does "smart" mean? Something like a 74HC4052 will give you a garden variety dual 4x1 switch. -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads

> >I am looking for a smart analog multiplexer 4 to 1 or a smart switch. If > >anyone knows where I can find this part, please let me know. I too am looking for something similar. I only need a 2:1 mux, but I need it to be suitable for switching NTSC video signals quickly (ie 29.94 Hz, or whatever it is). I need it to switch between two sources between each frame, and it has to be "clean" enough to not muck up the sync signal. Any ideas? -Steve -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads

> > >I am looking for a smart analog multiplexer 4 to 1 or a smart switch. If > > >anyone knows where I can find this part, please let me know. > > > I too am looking for something similar. > > I only need a 2:1 mux, but I need it to be suitable for switching NTSC > video signals quickly (ie 29.94 Hz, or whatever it is). I need it to > switch between two sources between each frame, and it has to be "clean" > enough to not muck up the sync signal. > > Any ideas? > Have you looked at Maxim http://para.maxim-ic.com/SwitchMux.asp Regards Chris p.s. Switching at Frame Rate is not (in video terms) switching "quickly" in fact this is the slowest switching rate. -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads

> p.s. Switching at Frame Rate is not (in video terms) switching > "quickly" in fact this is the slowest switching rate. Switching at frame rate is a heck of a lot quicker than my Sony home theatre receiver will let me do. I said "quickly" to impress that I didn't mean that I would be switching once every few minutes or so - and that I need to maintain a clean sync signal, etc. (ie a relay ainn't gonna cut it) -Steve -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads

Stephen B Webb wrote: > > > p.s. Switching at Frame Rate is not (in video terms) switching > > "quickly" in fact this is the slowest switching rate. > > Switching at frame rate is a heck of a lot quicker than my Sony home > theatre receiver will let me do. > > I said "quickly" to impress that I didn't mean that I would be > switching once every few minutes or so - and that I need to maintain a > clean sync signal, etc. (ie a relay ainn't gonna cut it) > > -Steve Steve, in the TV industry is it common to use the cheap 4066 quad analog switch chip for AV switching. I buy them by the bagful. They will switch at frame rate with no probs, and will switch the standard "AV inputs/outputs" that come from the back of your set. And they will commonly fail with weird faults after 6+ years in a hot environment. Especially the Toshiba brand chips. :o) -Roman -- http://www.piclist.com hint: The list server can filter out subtopics (like ads or off topics) for you. See http://www.piclist.com/#topics

steve: >switch between two sources between each frame, and it has to be "clean" >enough to not muck up the sync signal. I have used maxim analog switches for this in the past. obtaining stock from them was at times a bit scary as they were having some fab problems which they were not being too candid about. 'Standard' 4000 series analog muxers should do this job just fine (check the bandwidth specs to be sure as I have only used them for audio, but I seem to remember they had plenty of bandwidth to spare). You will get better results if you buffer the video into and out of the muxers (iirc you can get parts from Maxim with built in buffers). Remember you ideally want to time your switching point to be in the vertical blanking interval so's you don't get a visible switching point, this also means having locked video sources... if this is for a home system then you won't be able to do this so you need not worry about trying, just means you'll get a splat & probably some roll as you switch the signals. Regards, Simon -- http://www.piclist.com hint: The list server can filter out subtopics (like ads or off topics) for you. See http://www.piclist.com/#topics

>What on earth does "smart" mean? Sellspeak for >= 1 CMOS inverter used in the drive logic of the multiplexer. Peter -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.

>I only need a 2:1 mux, but I need it to be suitable for switching NTSC >video signals quickly (ie 29.94 Hz, or whatever it is). I need it to NJRC NJM22xx video buffers/switches I think. Peter -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.