Richard: I'm instersted in "the hot plug protection rules". For a CML type TX driver of a serial transceiver, what kind of circuit tricks shall we take to be compliant with hot plug rules? Regards, Neo --- On Thu, 7/10/08, Ward, Richard <richard.ward@xxxxxx> wrote: From: Ward, Richard <richard.ward@xxxxxx> Subject: [SI-LIST] Re: What will happen when short the SERDES IO to GND? To: "steve weir" <weirsi@xxxxxxxxxx>, "liuluping 41830" <liuluping@xxxxxxxxxx> Cc: "si-list@xxxxxxxxxxxxx" <si-list@xxxxxxxxxxxxx>, "wangyongjin@xxxxxxxxxx" <wangyongjin@xxxxxxxxxx> Date: Thursday, July 10, 2008, 5:12 AM As Steve says - it depends. Many XAUI style output drivers use majority passive termination to positive supply. By connecting the output nods to gnd you'll be bypassing the current control stage and starve it. Most nodes should survive with the (usually) 50 Ohms between rails for short times. Most will meet the hot plug protection rules. Long times on smaller feature sizes could permanently damage the die due to the high electro-migration. Depends on the design/linewidths. ESD doesn't tend to catch these events unless spikes at insertion/removal occur as well. But assumed you meant a DC short. "short" or "terminate"? - big difference naturally. Short will likely kill the signals, risks damage over time, terminate will likely give collapsed swing at best. Regards, Richard ------------------------------------------------------------------ To unsubscribe from si-list: si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field or to administer your membership from a web page, go to: //www.freelists.org/webpage/si-list For help: si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field List technical documents are available at: http://www.si-list.net List archives are viewable at: //www.freelists.org/archives/si-list or at our remote archives: http://groups.yahoo.com/group/si-list/messages Old (prior to June 6, 2001) list archives are viewable at: http://www.qsl.net/wb6tpu