All packages have some inductance and capacitance, and the package you are looking at is pretty much typical. Unless I've missed some cataclysmic change in packaging, I doubt your going to find something that is "matched" to your driver. You do not mention any transmission line parameters of length or impedance, so I wonder if you are modeling the driver pin directly connected to the FPGA pin. That's not realistic (you usually have some length of PCB trace between the pins), but would be simplest from a signal point of view, so you may have an issue with your HSPICE parameters. You may need to check the step size, among other parameters. Dennis Han posted a good summary on that subject to this list a couple days ago. You also mention looking at the output of the driver, but the point of interest is the input of the receiver. You may want to reconfigure your HSPICE deck to probe the receiver. Alan Hilton-Nickel Himanshu Arora wrote: >Hello, > >I need to take output from IC and interface it with an >FPGA and the question pertians to that. > >I have 1.8V rail-to-rail output from CMOS IC. It is a >80MHz signal, duty cycle atleast 50%, rise time around >1ns. The output driver in IC was designed assuming >15pF cap load (to take into account the package >capacitance, pcb track capacitance and the capaciatnce >due to FPGA package). This output becomes clock signal >for my FPGA. > >I made a model of the package assuming about 5nH >bondwire inductance and 2nH package lead inductance >(for an SOICE type package). on using this lumpled RLC >model of package in HSpice simulations I see a lot of >ringing in the output of the driver. > > Someone suggested me amkor MLF package with package >inductance of about 2nH... > >I am wondering is FPGAs come in some similar kind of >packages and if so how complicated this problem is of >interfacing a CMOS rail-to-rail output with 1ns rise >and fall time with an FPGA which can take 1.8V CMOS >inputs? Bascially I am looking for the right package. > >Thanks for your help. > >Sincerely > >Himanshu Arora > >__________________________________________________ >Do You Yahoo!? >Tired of spam? Yahoo! Mail has the best spam protection around >http://mail.yahoo.com >------------------------------------------------------------------ >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 FAQ wiki page is located at: > http://si-list.org/wiki/wiki.pl?Si-List_FAQ > >List technical documents are available at: > http://www.si-list.org > >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 > > > > > ------------------------------------------------------------------ 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 FAQ wiki page is located at: http://si-list.org/wiki/wiki.pl?Si-List_FAQ List technical documents are available at: http://www.si-list.org 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