David, Below is a Voltage Controlled Resistor (Gxxx) that I use to emulate a simple Pmos Pullup to speed up some SSO work. This is from Hspice. This one has piece wise linear control to emulate the IV curve but you can simplify it to a simple linear equation Gpmos psource drain VCR NPWL(1) pgate die_vss LEVEL=1 0.25v,'150g/(pgain*psso)' + 0.5v,'10meg/(pgain*psso)' 1v,'50k/(pgain*psso)' 2v,'4k/(pgain*psso)', 3v,'2k/(pgain*psso)' This is the gate voltage control used to turn on the VCR. Vpgate pgate die_vss PWL 0n 0V 7.5ns 0V 8.0nS 3V 15.0ns 3V 15.5ns 0V Hope this helps. The pgain and psso are just parameters I use to set the drive strength and number of Pmos in parallel. Steve Waldstein swldstn@xxxxxxxxxxxx -----Original Message----- From: si-list-bounce@xxxxxxxxxxxxx [mailto:si-list-bounce@xxxxxxxxxxxxx]On Behalf Of Beal, Weston Sent: Tuesday, October 14, 2003 7:38 PM To: 'david.kaiser@xxxxxxxxxx'; si-list@xxxxxxxxxxxxx Subject: [SI-LIST] Re: How to build a variable resistor in HSPICE David, I'm pretty sure that Hspice has an element called a voltage controlled switch that will do this. It takes ON and OFF resistances as parameters. Later, Weston -----Original Message----- From: David Kaiser [mailto:david.kaiser@xxxxxxxxxx] Sent: Tuesday, October 14, 2003 3:55 PM To: si-list@xxxxxxxxxxxxx Subject: [SI-LIST] How to build a variable resistor in HSPICE Can anyone show me how to build a resistor in HSPICE that varys in value= from 1000 Ohms to 1 ohm in about 1ns and visa-versa? I suppose I could use a FET, but I don't have enough experience with= transistors in HSPICE to do this myself. Thanks in advance. David Kaiser 4 McDATA Pkwy. Broomfield, CO 80021 (720) 558-4431 david.kaiser@xxxxxxxxxx ------------------------------------------------------------------ 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 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 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