I never use the E element to simulate the crystal. Your problem may come from the phase. Here, the crystal_in and crystal_out has the same phase (controlled by the VCVS). I believe they should be 180 degree different. You may also need to consider the DC feedback. Usually, a resonator has a feedback resistor such as 500Kohm but a crystal doesn't have. Suppose you use a CMOS inverter as the amplifier, you need a feedback resistor. Regards, Haixiao On 6/19/08, Lurker <lurker_li@xxxxxxxxx> wrote: > > Hi Beal, > > I'm li. Please check the script. It doesn't work. > > *Crystal sim > > .option acct post list > > .param cu=2 > E1 a1 0 a4 0 max=+3.3 min=0 cu > > L1 a1 a2 0.08h > C1 a2 a3 8pf > R1 a3 a4 600 > c2 a1 a4 8pf > c3 a1 0 22pf IC=0.5 > c4 a4 0 22pf IC=0.5 > R2 a1 a4 1m > > > .temp 50 > .tran 10ps 100ns start=0ns > > .print PAR('v(a1)') > > .end > > > Best Regards, > > Lurker Li > > Tel: 86-21-58966996-1021 > > > -----Original Message----- > From: si-list-bounce@xxxxxxxxxxxxx [mailto:si-list-bounce@xxxxxxxxxxxxx] > On > Behalf Of Beal, Weston > Sent: Wednesday, June 18, 2008 10:45 PM > To: si-list@xxxxxxxxxxxxx > Subject: [SI-LIST] Re: How to do crystal simulation > > =20 > Based on your description of you circuit, I would not expect it to = > oscillate. An oscillator needs some amplification element and all of you = > circuit is passive elements. You should find a reference on basic = > oscillator design. > http://en.wikipedia.org/wiki/Pierce_oscillator > > It sounds like you got your circuit from an IC design guide that = > suggested a circuit for the input to a clock generator. The part you = > missed is that the IC itself provides the amplifier that you are missing = > in your circuit. > > Regards, > Weston > > > -----Original Message----- > From: si-list-bounce@xxxxxxxxxxxxx [mailto:si-list-bounce@xxxxxxxxxxxxx] = > On Behalf Of ? ? > Sent: Wednesday, June 18, 2008 6:40 AM > To: si-list@xxxxxxxxxxxxx > Subject: [SI-LIST] Re: How to do crystal simulation > > Hi David and Haixiao > =20 > Thank you!=20 > I just got the crystal internal circuit. It's L. C. R in serial and = > parallel with a C. > I will have a try in Hspice with a initialized capacitor or inductor.=20 > The outside circuit is two capacitor( both of them is about 22ps) = > connected crystal's output and input with a R(1Mohm) in parallel. > I don't have ADS tool. So I can't use it. If necessory I will release = > the Hspice simulation script tomorrow night. Then you can see the = > electrical circuit clearly. > I'm not sure whether it can run or not.=20 > =20 > =20 > =20 > > "Pommerenke, David" <davidjp@xxxxxxx> =D0=B4=B5=C0=A3=BA > Li, > > Your attached file was not delivered, but normally I just set initial = > conditions on the capacitor or the inductor that is part of the XTAL = > model. > > > Dr. David Pommerenke > Missouri University of Science and Technology (MST), former name: UMR > 118 EECH, 301 W. 16th Street, Rolla, MO 65409-0040 > 573 341 4531, cell: 573 308 2019 > > > =20 > Did you add stimulus to start the spice simulation? For example, a 1ns = > pulse. > ADS has more choice on crystal simulation. Check the ADS help on = > oscillators. > > Regards, > Haixiao > > > -----Original Message----- > From: si-list-bounce@xxxxxxxxxxxxx [mailto:si-list-bounce@xxxxxxxxxxxxx] = > On Behalf Of ? ? > Sent: Tuesday, June 17, 2008 8:35 AM > To: si-list@xxxxxxxxxxxxx > Subject: [SI-LIST] How to do crystal simulation > > Hi all, > > I have a problem with crystal simulation. Please check the attached. I = > can't get the crystal start to "shake". The frequency I want to get is = > 25MHz. I didn't get the internal circuit for crystal. The Pspice model = > seems didn't work. What shall I do? > > > > > > > > =20 > --------------------------------- > = > =D1=C5=BB=A2=D3=CA=CF=E4=A3=AC=C4=FA=B5=C4=D6=D5=C9=FA=D3=CA=CF=E4=A3=A1 > > ------------------------------------------------------------------ > 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: =20 > //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 > =20 > > ------------------------------------------------------------------ > 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 > > > ------------------------------------------------------------------ > 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 > > > ------------------------------------------------------------------ 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