Help with Pspice Capture Bias Point Calculation Errors

In summary, the conversation is about a person who is using Pspice for the first time and following a user's guide to do bias point calculation. However, they encounter an error regarding undefined diodes. Another person suggests using the full part name and editing the model parameters. The first person confirms that it worked and expresses their gratitude. Others also mention their similar problems and seek help in fixing them. The conversation also touches on accessing libraries and using the power ground feature.
  • #1
ram0001
5
0
Hi all,
This is first time I am using Pspice. I have 9.1 student version.
I am using Pspice capture user's guide for reference. Following an example from there, I was trying to do bias point calculation using Capture.
I have no knowledge about Pspice and I am following the user's guide only.

But when I tried to run it ,using mentioned steps,... I am getting some errors.
It says 'undefined diodes'.
I am hereby attaching log file for your reference.

-------------------------------------------------------------------------------------

**** 02/07/07 18:13:40 *********** Evaluation PSpice (Nov 1999) **************

** Profile: "SCHEMATIC1-Bias" [ C:\Program Files\OrCAD_Demo\Capture\clipper-SCHEMATIC1-Bias.sim ]


**** CIRCUIT DESCRIPTION


******************************************************************************




** Creating circuit file "clipper-SCHEMATIC1-Bias.sim.cir"
** WARNING: THIS AUTOMATICALLY GENERATED FILE MAY BE OVERWRITTEN BY SUBSEQUENT SIMULATIONS

*Libraries:
* Local Libraries :
* From [PSPICE NETLIST] section of pspiceev.ini file:
.lib "nom.lib"

*Analysis directives:
.PROBE
.INC "clipper-SCHEMATIC1.net"


**** INCLUDING clipper-SCHEMATIC1.net ****
* source CLIPPER
V_V1 VCC OUT 5v
R_R1 IN MID 1k
R_R4 OUT OUT 5.6k
D_D1 N00100 VCC D1N3940
R_R2 N00097 VCC 3.3
R_R3 N00097 OUT 3.3k
D_D2 OUT N00100 D1N3940
V_VIn IN OUT 0Vdc
C_C1 MID OUT 0.47u

**** RESUMING clipper-SCHEMATIC1-Bias.sim.cir ****
.INC "clipper-SCHEMATIC1.als"



**** INCLUDING clipper-SCHEMATIC1.als ****
.ALIASES
V_V1 V1(+=VCC -=OUT )
R_R1 R1(1=IN 2=MID )
R_R4 R4(1=OUT 2=OUT )
D_D1 D1(1=N00100 2=VCC )
R_R2 R2(1=N00097 2=VCC )
R_R3 R3(1=N00097 2=OUT )
D_D2 D2(1=OUT 2=N00100 )
V_VIn VIn(+=IN -=OUT )
C_C1 C1(1=MID 2=OUT )
_ _(mid=MID)
_ _(In=IN)
_ _(Vcc=VCC)
_ _(Out=OUT)
_ _(GND_POWER=OUT)
.ENDALIASES

**** RESUMING clipper-SCHEMATIC1-Bias.sim.cir ****
.END

ERROR -- Model D1N3940 used by D_D1 is undefined
ERROR -- Model D1N3940 used by D_D2 is undefined

-------------------------------------------------------------------------------

If anybody can help me in understanding this error and how to remove it... that would be a great help. I really appreciate if some one can help.
Thanks,
 
Engineering news on Phys.org
  • #2
I don't know this software, but...
I'll guess that D1N3940 is an invalid diode identifier.
Try removing the D and use 1N3940.
 
  • #3
I confirmed that you do need the full part name (D1N3940). Your output file seems to be missing the model parameters. You can right click on the part in Capture and click on EDIT PSPICE MODEL. You should have something that looks like this:

.MODEL D1N3940 D(
+ IS = 4E-10
+ RS = .105
+ N = 1.48
+ TT = 8E-7
+ CJO = 1.95E-11
+ VJ = .4
+ M = .38
+ EG = 1.36
+ XTI = -8
+ KF = 0
+ AF = 1
+ FC = .9
+ BV = 600
+ IBV = 1E-4
+ )
*
 
  • Like
Likes Os95
  • #4
Thanks for you help.
I will try implementing your suggestions.
Thanks for your time
 
  • #5
It worked.
WOW!

Thanks you.
 
  • #6
Thats good news. I wonder why it wasn't there?
 
  • #7
Hi,

Im having the same problem, but when i right-click on the part, there is no option for editing the part. I am using 9.1 student version of orcad.
 
  • #8
andi, left click on the part, click Edit ~> Model ~> Edit Instance Model (text)

I use the text one because it's pretty straightforward to change a spec (delete old value, type in the new one, hit save)

this will change the specs on just that single part, not every single one

EDIT: whoops, that was for PSpice, I'm not sure if orcad is the same. sorry
 
  • #9
Hi everybody! I have the problem like ram0001's, but when I right click on the part in Capture and click on EDIT PSPICE MODEL, a message appear and yell that "Error-Model D1 3940 Not Found!". I don't know how to fix it! Do I need making a file with the content of emlombardo and put it into any folder to make it run? Thank you so much if anyone can help me! Thank for your help!

I don't know why my OrCAD Capture 9.2 hide the choices "analog and Mixed A/D" and "Programable logic wizard" when I make new project.
 

Attachments

  • Untitled.jpg
    Untitled.jpg
    21 KB · Views: 947
Last edited:
  • #10
pspsice is now owned by orcad so fundamentally the same...

when accessing libraries, at start up, ensure you add libraries for your poject that are pspice enabled...some libraries are only for stuff like schematic, pcb etc...

the main library i use to test an idea is the breakout library...always load that one for your tests...it includes all your basic needs...

also, for ground, use the power ground that has the zero label and that will take care of any ground errors you get. normally accessed from the drop down power menu...depending on the version you have.
 

1. What is PSpice Capture and how does it calculate bias point errors?

PSpice Capture is a software tool used for circuit simulation and design. It calculates bias point errors by analyzing the circuit and determining the appropriate voltage and current values at each node in the circuit. Bias point errors can occur when the circuit is not properly designed or when there are errors in the component values or connections.

2. How can I fix bias point errors in PSpice Capture?

To fix bias point errors, you can try adjusting the circuit design, checking for errors in component values or connections, and using the "Bias Point" option in the simulation settings. You can also try using the "Convergence Assistant" tool to help identify and fix any issues.

3. What is the "Bias Point" option in PSpice Capture and when should I use it?

The "Bias Point" option in PSpice Capture allows you to specify a starting point for the simulation, which can help prevent bias point errors. It should be used when the circuit has complex nonlinear components or when the circuit has multiple DC sources.

4. How do I know if my PSpice Capture bias point calculations are accurate?

You can check the accuracy of your bias point calculations by comparing them to the expected values from your circuit design. You can also use the "Probe" tool in PSpice Capture to view the voltage and current values at each node in the circuit and compare them to the calculated values.

5. Are there any common mistakes that can lead to bias point errors in PSpice Capture?

Some common mistakes that can lead to bias point errors in PSpice Capture include incorrect component values, incorrect connections, and improperly defined voltage and current sources. It is important to carefully review your circuit design and simulation settings to ensure that all parameters are accurately specified.

Similar threads

  • Engineering and Comp Sci Homework Help
Replies
6
Views
6K
Back
Top