David, I=20am=20not=20aware=20of=20any=20references=20that=20specifically=20model= =20the=20ohmic contact=20region=20say=20from=20a=20transmission=20line=20into=20a=20resis= tive=20material. As=20a=20developer=20and=20manufacturer=20of=20PCB=20embedded=20passives=20= I=20would=20also=20be interested=20in=20references=20that=20others=20on=20this=20list=20may=20kn= ow.=20In=20the=20lack of=20information=20I=20would=20suggest=20considering=20time=20domain=20mea= surements=20from a=20signal=20launched=20from=20a=20transmission=20line=20into=20an=20embed= ded=20passive component. Keep=20in=20mind=20as=20you=20go=20through=20the=20thought=20exercise=20fo= r=20making=20such measurements=20that=20other=20factors=20may=20become=20more=20important=20= in=20the=20final analysis=20of=20the=20exercise.=20Depending=20on=20the=20frequency=20space= =20you=20are designing=20in=20the=20geometric=20shape=20of=20the=20resistor=20element=20= and=20design=20of the=20conductive=20ohmic=20contacts=20will=20have=20an=20effect=20on=20the= =20frequency response=20of=20the=20circuit.=20Ohmic=20contacts=20for=20metal=20thin=20f= ilm=20resistors such=20as=20Ohmega-Ply=20and=20Ticer=20TCR=20are=20significantly=20differe= nt=20than=20the contacts=20for=20polymer=20thick=20film=20resistor.=20The=20other=20major=20= consideration to=20frequency=20response=20is=20the=20relative=20location=20of=20the=20em= bedded=20passive to=20your=20reference=20planes. Hope=20this=20helps=20in=20your=20design=20efforts.=20If=20you=20need=20ad= ditional information=20on=20manufacturability=20contact=20me=20directly=20by=20emai= l. Nick=20Biunno Sanmina-SCI,=20Inc. nick_biunno@xxxxxxxxxxxxxx=20=20=20 -----Original=20Message----- From:=20si-list-bounce@xxxxxxxxxxxxx=20[mailto:si-list-bounce@xxxxxxxxxxxx= g] On=20Behalf=20Of=20Tate,=20David Sent:=20Wednesday,=20July=2025,=202007=206:24=20AM To:=20si-list@xxxxxxxxxxxxx Subject:=20[SI-LIST]=20Embedded=20Passives Are=20there=20any=20pitfalls=20in=20performing=20SI=20analysis=20when=20us= ing=20embedded passives? =20 Modeling=20the=20plane=20capacitances=20looks=20straight=20forward=20-=20d= istance between=20the=20planes,=20the=20dielectric=20constant,=20tangent=20loss=20= etc...=20should be=20all=20I=20need. =20 We=20are=20looking=20at=20products=20like=20Ohmega-Ply=20to=20provide=20em= bedded resistors.=20How=20do=20I=20model=20the=20transition=20from=20the=20copper= =20trace=20to=20the resistive=20material,=20or=20can=20I=20ignore=20this=20transition=20region= ? =20 best=20regards, =20 David=20Tate Lockheed=20Martin=20Missiles=20and=20Fire=20Control Senior=20Staff=20Circuit=20Design=20Engineer Electrical=20Engineering=20-=20FPGA/Processor=20Design E-Mail:=20david.tate@xxxxxxxx=20<mailto:david.tate@xxxxxxxx> ------------------------------------------------------------------ To=20unsubscribe=20from=20si-list: si-list-request@xxxxxxxxxxxxx=20with=20'unsubscribe'=20in=20the=20Subject=20= field or=20to=20administer=20your=20membership=20from=20a=20web=20page,=20go=20t= o: //www.freelists.org/webpage/si-list For=20help: si-list-request@xxxxxxxxxxxxx=20with=20'help'=20in=20the=20Subject=20field= List=20technical=20documents=20are=20available=20at: =20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20http://www.si-list.net List=20archives=20are=20viewable=20at:=20=20=20=20=20 =09=09//www.freelists.org/archives/si-list or=20at=20our=20remote=20archives: =09=09http://groups.yahoo.com/group/si-list/messages Old=20(prior=20to=20June=206,=202001)=20list=20archives=20are=20viewable=20= at: =20=09=09http://www.qsl.net/wb6tpu =20=20 CONFIDENTIALITY This=20e-mail=20message=20and=20any=20attachments=20thereto,=20is=20intend= ed=20only=20for=20use=20by=20the=20addressee(s)=20named=20herein=20and=20m= ay=20contain=20legally=20privileged=20and/or=20confidential=20information.= =20If=20you=20are=20not=20the=20intended=20recipient=20of=20this=20e-mail=20= message,=20you=20are=20hereby=20notified=20that=20any=20dissemination,=20d= istribution=20or=20copying=20of=20this=20e-mail=20message,=20and=20any=20a= ttachments=20thereto,=20is=20strictly=20prohibited.=20=20If=20you=20have=20= received=20this=20e-mail=20message=20in=20error,=20please=20immediately=20= notify=20the=20sender=20and=20permanently=20delete=20the=20original=20and=20= any=20copies=20of=20this=20email=20and=20any=20prints=20thereof. ABSENT=20AN=20EXPRESS=20STATEMENT=20TO=20THE=20CONTRARY=20HEREINABOVE,=20T= HIS=20E-MAIL=20IS=20NOT=20INTENDED=20AS=20A=20SUBSTITUTE=20FOR=20A=20WRITI= NG.=20=20Notwithstanding=20the=20Uniform=20Electronic=20Transactions=20Act= =20or=20the=20applicability=20of=20any=20other=20law=20of=20similar=20subs= tance=20and=20effect,=20absent=20an=20express=20statement=20to=20the=20con= trary=20hereinabove,=20this=20e-mail=20message=20its=20contents,=20and=20a= ny=20attachments=20hereto=20are=20not=20intended=20to=20represent=20an=20o= ffer=20or=20acceptance=20to=20enter=20into=20a=20contract=20and=20are=20no= t=20otherwise=20intended=20to=20bind=20the=20sender,=20Sanmina-SCI=20Corpo= ration=20(or=20any=20of=20its=20subsidiaries),=20or=20any=20other=20person= =20or=20entity. ------------------------------------------------------------------ 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