Hi, Thanks.
I think I should have been more specific. We've got an RS485 comms pair, which we want to multiplex between 120 RS485 pairs. I.e. 120 channels to 1 (or 240 to 2 in terms of actual wires). Ive seen a 32 channel analogue switch from Analogue devices, but im unsure as to whether an Analogue switch will be ok? Regards, Darren -----Original Message----- Declan Moriarty Sent: 23 August 2005 16:24 To: Multiple recipients of list CHIPDIR-L Recently, Somebody Somewhere wrote these words > im wanting to multiplex 2 digital lines, to 120 channels (pairs) > using digital switches > can some suggest a digital chip with the most channels on it, > please? > > Best regards Darren Logan That's not very much to go on. How much pain do you want? The 4051 switches to 8 at a time. But you want digital switches. http://www.chipdir.nl/giicm/4514.txt gives 16, which isn't bad for cmos or 74xx and allows you to proceed fairly painlessly. If you are prepared for a little pain, use a latching shift register and grab the info as a pulse stream. Reset Everything, latch & clock it for a sequential input. It you want to go through more pain, you could put an overgrown 8255 in - something like the hd63140ps (5 or 6 ports) If you want to go through some real pain, you could put in an fpga. -- With best Regards, Declan Moriarty. -- Author: Declan Moriarty INET: [EMAIL PROTECTED] Fat City Hosting, San Diego, California -- http://www.fatcity.com --------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB CHIPDIR-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing). -- Author: Darren Logan INET: [EMAIL PROTECTED] Fat City Hosting, San Diego, California -- http://www.fatcity.com --------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB CHIPDIR-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing).
