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Struggling to create PCB layout, missing footprints.

Learning orcad. Created a project in capture using pc board wizard.

Drew simple circuit containing a BZX84C12/ZTX zener from the zetex library that shipped with orcad.

Following instructions from http://encon.fke.utm.my/nikd/PSM1/PCB_layout/PCBorcadpcb.pdf exported layout netlist.

Trying to create project in Layout (or Layout Plus or Layout Engineer's Edition or Layout PSpice Orcad Ultra A/D Super Duper or Layout Engineer University Edition Plus Japan or whatever tool I'm actually using).

It says no footprint for component. I try to link existing component. I pick one with two pads e.g. DAX/1N_4001-4007 from TM_DIODE.

Error says "electrical package bzx84c12/ztx forcomp d1 has at least one pin (1) which has no corresponding pin on footprint". Unclear as to how to proceed, as component has two pins, footprint has two pads, component is a diode, and footprint is from a library for diodes.

Please advise as project is now on hold.

Thanks.

mnbv0987 over 13 years ago

According to capture diode pin names are 1 and 2. Tried using DAX1/* and DAX2/* footprints from TM_DIODE which have pads labelled 1 and 2. Error now says "at least one pin (0)", but diode model does not appear to have a pin named 0. Please advise.
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redwire over 13 years ago

Sounds like you want to push a button and it all works out? That doesn't happen with *any* pcb/schematic tool.
What you are seeing is that the footprint has been constructed with a set of pads that may be labeled "A" and "C" for anode/cathode respectively. The OrCAD schematic sounds like it is using pin 1, pin 2 for the diode. And by the way, the industry standard is pin 1 is cathode which is typically reversed in most OrCAD libraries.
So you need to get a matching footprint or correct the schematic symbol. Either way the two objects have to have 1:1 matching pins in order to be associated to each other.
There are plenty of user manuals that come with the tools to help with this.
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mnbv0987 over 13 years ago

Thank you.

I am not expecting to push a button but I am expecting reasonable out-of-the-box consistency between tools in the "integrated" orcad suite, e.g. some compatibility between the models orcad capture ships with and the footprints orcad layout provides, especially given the cost of this software. As of yet I have not found any footprints compatible with any of the capture models.

I resolved the diode issue by modifying one of the apparently functionless-out-of-the-box layout footprints to use pin names 0 and 1.

I am now struggling with a mosfet in a to263 package. The to263 footprints that ship with orcad have pads 1, 2, and 4, which do not correspond to the mtb1306/on model that also ships with orcad, whose pin names I am currently trying to determine as capture shows them as d, s, and g, and the pspice model lists them as 1, 2, and 3, and apparently neither match what was exported in the layout net listing as layout says pin 0 is unmatched. How do I determine the correspondance between capture and pspice models and what layout expects?

Adding to the frustration is the fact that the layout autoeco dialog is not owned by the layout window nor does it appear in the taskbar, meaning that I have to repeatedly minimize all open application windows to get back to autoeco dialog if I focus away from it. Then I had to start over because layout crashed.

On top of that, I created a new footprint for the mosfet, and despite saving the library and seeing the model in footprint in the maxeco list, it spuriously complained that the footprint was not found until I closed layout and restarted it (which also compounds the irritation because the "Use as default" check box in the Cadence Product Choices dialog has no effect).

Additionally, while I would find the "search footprint" functionality useful, it does not actually search the libraries listed/selected in the maxeco footprint chooser where the search button is, despite having "configured libraries" checked. Pressing the "help" button on the dialog was a no-op, help did not display, but fortunately I have the manual right here. Unfortunately I cannot locate any information regarding the footprint search dialog.

I would have replied here sooner but the forum server crashed and was down for about an hour.

Off-topic, when pspice wasn't failing to converge, after much headscratching I discovered that the TL082 model in OPAMP.OLB is entirely broken -- fortunately TL082/301/TI works fine. I will make a separate post about that.

I believe my expectations are quite reasonable.

Anyways, the current issue is finding the MTB1306/ON pin names as expected by layout.

For reference here is the pspice model - how can I determine which pin is 0, 1, and 2 as expected by layout?

.SUBCKT mtb1306/ON 1 2 3</div><div>**************************************</div><div>*      Model Generated by MODPEX     *</div><div>*Copyright(c) Symmetry Design Systems*</div><div>*         All Rights Reserved        *</div><div>*    UNPUBLISHED LICENSED SOFTWARE   *</div><div>*   Contains Proprietary Information *</div><div>*      Which is The Property of      *</div><div>*     SYMMETRY OR ITS LICENSORS      *</div><div>*Commercial Use or Resale Restricted *</div><div>*   by Symmetry License Agreement    *</div><div>**************************************</div><div>* Model generated on Dec 11, 98</div><div>* MODEL FORMAT: PSpice</div><div>* Symmetry POWER MOS Model (Version 1.0)</div><div>* External Node Designations</div><div>* Node 1 -> Drain</div><div>* Node 2 -> Gate</div><div>* Node 3 -> Source</div><div>M1 9 7 8 8 MM L=100u W=100u</div><div>.MODEL MM NMOS LEVEL=1 IS=1e-32</div><div>+VTO=2.04213 LAMBDA=0 KP=161.241</div><div>+CGSO=2.48389e-05 CGDO=1e-11</div><div>RS 8 3 0.00475798</div><div>D1 3 1 MD</div><div>.MODEL MD D IS=1.8541e-10 RS=0 N=1.13751 BV=30</div><div>+IBV=10 EG=1.2 XTI=2.69158 TT=0.0001</div><div>+CJO=4.69655e-09 VJ=0.638331 M=0.445058 FC=0.5</div><div>RDS 3 1 1e+06</div><div>RD 9 1 0.0001</div><div>RG 2 7 6.86824</div><div>D2 4 5 MD1</div><div>* Default values used in MD1:</div><div>*   RS=0 EG=1.11 XTI=3.0 TT=0</div><div>*   BV=infinite IBV=1mA</div><div>.MODEL MD1 D IS=1e-32 N=50</div><div>+CJO=4.36355e-09 VJ=0.5 M=0.653132 FC=1e-08</div><div>D3 0 5 MD2</div><div>* Default values used in MD2:</div><div>*   EG=1.11 XTI=3.0 TT=0 CJO=0</div><div>*   BV=infinite IBV=1mA</div><div>.MODEL MD2 D IS=1e-10 N=0.410863 RS=3e-06</div><div>RL 5 10 1</div><div>FI2 7 9 VFI2 -1</div><div>VFI2 4 0 0</div><div>EV16 10 0 9 7 1</div><div>CAP 11 10 4.36355e-09</div><div>FI1 7 9 VFI1 -1</div><div>VFI1 11 6 0</div><div>RCAP 6 10 1</div><div>D4 0 6 MD3</div><div>* Default values used in MD3:</div><div>*   EG=1.11 XTI=3.0 TT=0 CJO=0</div><div>*   RS=0 BV=infinite IBV=1mA</div><div>.MODEL MD3 D IS=1e-10 N=0.410863</div><div>.ENDS </div><div>

This forum has no preview button so if it does not recognize code tags, pardon the mess while I edit it.

Thanks.

Edit: Code tags came out worse than expected. Sigh... it's here: http://pastebin.com/hABVMB84
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mnbv0987 over 13 years ago

I solved the problem by using EAGLE for schematic editing and PCB layout, as Orcad's integration between Capture and Layout basically does not exist, and every part and footprint that ship with EAGLE's standard libraries correspond with each other.
Why Orcad ships with Capture parts that do not match the Layout footprints it also ships with is only explainable by poor or nonexistent QA at Cadence - which is inline with the stability and quality of the rest of the software in this "suite".
That said Capture + PSpice is still a valuable tool. Layout, however, should not be included in the package until it's run through some actual QA and testing. It's major version 16. Sixteen. These types of issues should not be present in the sixteenth major revision of a professional software package.
Also reflecting on Cadence's QA abilities is the fact that the quick reply I just entered removed all line breaks from the text (in addition to all of the web site issues mentioned above). And I'm still getting consistent server errors when I click the forum links at the top of the page (see my post in the site forum), so now I have to find a way back to the new post page... wish me luck.
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