> As for TTL specification, "0" voltage must be between 0 and 0.8V, and "1" > voltage must be between 2.4 and 5V, so LVTTL (3.3V)with their levels must > comply with TTL spec. So, I don't see any is no problem if you connect > zener-protected pins (5V tolerant) to 3.3V system.
This is the biggie -- it's already all 5V compliant and safe, and the PCI 2.2 spec says that everything on the PCI bus must be 5V tolerant (it's been a while since I've been reading the spec, I might be wrong) -- but yeah -- Voh on the Spartan-II is 90% of Vcco on both the 5V and 3.3V pads. Interestingly enough the PCI33_3 minimum Voh is 300mV higher than the PCI33_5 pad specification. > There was for Xilinx. But what about PEF? As I see for one used for TE410P > (to remember - I don't have TE405P to check which chips used for it), there > was 3.3V-only chips, so IMHO TE405P must have any sort of 3.3V source (from > onboard regulator or from PCI connector). PEF? You mean the quad T1 framer? That is all sufficiently isolated from the PCI bus that I don't think it'd be a problem, and 5V power is available even on 3.3V PCI sockets. > Any way, I don't see any problems to connect TE405P to 3.3V bus (after > making second, 3.3V, key hole). But I'm not Digium's hardware engineer... > ;-)' I think there would be dual-voltage TE405P+ cards (TE405P with two key > holes) available when all TE410P "already-made" will be sold out. ;-)' Well I am glad that I'm not the only one who thinks it might be possible. I realize that neither of us have the real answer. I am hoping that someone from Digium replies with a "definitely UNSUPPORTED, WARRANTY-VOIDING" type of response. I'm gonna give it a few more days to build up my courage about frying a $1500 card and possibly high-end motherboard too... but this is the kind of thing I live for. :-) Regards, Andrew _______________________________________________ Asterisk-Dev mailing list [EMAIL PROTECTED] http://lists.digium.com/mailman/listinfo/asterisk-dev To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-dev