Questions tagged [cad]
Computer Aided Design
111
questions
0
votes
0answers
50 views
Altium interactive routing strange behaviour
Probably after I pressed by mistake a wrong key while routing, my routing style changed during interactive routing only for one of my projects.
The differences I could spot between my "normal" ...
0
votes
1answer
32 views
When placing a new line it doesn't get assigned a net, how to fix it in Altium?
I had this working well before, but now, every time i'm placing a new line from a component, it never gets assigned the net.
In the Net field it is always "No Net", which forces me to manually place ...
0
votes
3answers
126 views
KiCAD parametric component placement
I need to place components in a circle of a certain diameter, with a certain pitch, and angled evenly.
Is possible to do it in KiCAD automatically?
1
vote
1answer
107 views
Eagle Library Missing Micro b Connector?
I'm not sure if this post belongs here or in another community but here we go. I'm working with Eagle cad (pcb) and i'm looking through the libraries and I couldn't find a single MICRO b usb connector....
1
vote
1answer
46 views
Representing Heatsinks on board layout
When using CAD software to draw board layouts, is there any convention on how to represent heatsinks attached to, say, some power transistors? I want to make sure they don't interfere with one another,...
0
votes
0answers
40 views
Eagle right angle bending wire
How do I make sure wires go over the grid when drawing a schematic(Not layout) in Eagle?
i.e they always bend at a right angle
0
votes
2answers
521 views
How to import PCB 3D model (step file) designed in MCAD software in Altium and place PCB footprints, and route it?
I have my PCB board from Mechanical Design software as a Step file. Now, I want to import it into Altium Designer and place PCB footprints, and do the routing etc. I am looking for some guidelines or ...
0
votes
1answer
154 views
LTSpice error with V() function, … when referencing net within a subckt (V(subCktName.NetName))
I've converted an IBIS model to a SPICE model using microCap, and am trying to simulate that subckt with LTSpice.
Using LTspice, I get an error with the subckt in the library.
"u1:g1: Unknown ...
0
votes
1answer
58 views
LTSpice error with the V() function in a subcircuit
I'm trying to do a simulation with a subcircuit, and I've narrowed down the issue to the V() function.
The simulation fails with the message 'can't find definition of model "V" '
Here is the spice ...
1
vote
1answer
42 views
Altium Designer 16.1 Can't find Pin in Place Menu
I am new to Altium, so this is probably a stupid question. I want to place a pin in a schematic, as described here.
But I cannot find pin in any of the menus.
No pins anywhere... What am I doing ...
0
votes
0answers
23 views
Design/Simulation and on-chip microfabrication of a 2D/thin-film bias tee with narrow bandwidth around 200 MHz
What is necessary and a possible design to realize a bias tee for on-chip integration and the AC electrical connection of two 200 MHz nano-rf-oscillators (both DC-fed with 1-10 mA) and creating an AC ...
0
votes
1answer
58 views
Annotate block in Proteus
How can I annotate a block in Proteus 8 (automatically)? For example, let's suppose I design a multiplexer and I embed it in a block and I need to copy it several times. How can I make Proteus ...
1
vote
0answers
48 views
Anneal Placement
I'm doing a practice assignment, and I cant seem to understand this question.
They give 6 gates in a small 6x6 grid.
Each gate is drawn as a circle with number. There are 4 nets, labeled A, B, C and ...
0
votes
1answer
39 views
Why only shared resistances are taken into consideration while computing Elmore delay?
While we compute the delay , using Elmore delay model we take into consideration the shared resistance and capacitance. I would like to know why are we only concerned with shared resistance not the ...
3
votes
2answers
235 views
Why are project files in Altium modified every time they are opened? Is there a way to prevent this?
I use Altium Designer 18. When I open a project file (.PrjPCB), the asterisk ("*") appears next to the project name indicating that the project has been modified, but I haven't actually made any ...
0
votes
1answer
54 views
On adding components in Eagle schematic same are not reflected on Eagle board else link error pops-up?
While adding new components to Schematic same are not reflected on board. Forward/Backward annotations cannot be performed. How Re-link the schematic and board so that I can add new components?
or
Can ...
0
votes
2answers
65 views
Deducing the CAD program used to make a schematic
I've received a reference schematic from a company whose chips I'm interested in using. After studying it for a while and copying the schematic into the CAD program I'm most familiar with, I have ...
-9
votes
1answer
102 views
Where to find parameters of a component in Altium Designer [closed]
Where can I find the parameters of a selected component in the schematic editor?
0
votes
2answers
68 views
EagleCad Warning errors
Is it normal for me to be getting these warnings when I changed the names of the wires?
0
votes
1answer
55 views
How to simulate a component hspice model in multisim
I'm trying to simulate TS5A22364 and they have hspice and ibis models, and CAD model .bxl in Multisim. Is it possible?
I have tried to add the package model but I don't know how to add the .bxl model ...
2
votes
4answers
118 views
Basic Eagle question about DIPs in schematics
I just started using Eagle this morning, and I've read/watched some tutorials, but with no luck on this question; please forgive my naivete.
I want to insert an LM324 (quad op-amp) into a schematic. ...
0
votes
1answer
325 views
In EAGLE, why is the ground pour not connected to these SMD pads?
There are some SMD pads in my schematic that are connected to ground, but do not appear as connected on the board. Any help on how to solve this?
This happens for all pads except 12, which is also ...
0
votes
0answers
147 views
Visual circuit simulation on a Mac
I am currently trying to design a circuit on a Mac (some might say therein lies my problem).
My goal is simply to design a rudimentary implementation of the circuit which I can visualise working
I ...
0
votes
0answers
2k views
Wiring Diagram Software for Open Source Projects
So, obviously, there are plenty of CAD software options out there for hobbyists and open source hardware folks to do PCB schematic capture and layout.
However, I'm having a really hard time figuring ...
0
votes
2answers
1k views
Import step model into HFSS [closed]
I have a step file and I want to simulate it in HFSS but it seams that the structure it is not made with solids, but with attached sheets because when I import it in HFSS I cannot define materials and ...
3
votes
3answers
966 views
Altium schematic editor colours
I've just started doing some work for a company doing some CAD work where they use Altium 16. (16.1.10 to be precise.)
I've used umpteen CAD systems over the years, but done very little Altium. I ...
0
votes
2answers
203 views
Eagle - placing pin number silkscreen
I'm fairly new to PCB designing, and it's my first board design.
If I want to add pin number silkscreen on the board, do I have to do it all manually on the board design page?
Can't I do it on ...
0
votes
1answer
143 views
Eagle CAD autorouter places tracks too close to vias
Eagle CAD autorouter places tracks too close to vias. I tried to change some parameters in the design rules but without a good result.
0
votes
2answers
174 views
Eagle PDF Out Print
How can I print a PDF with defining how many pages I want to print out. The option (Page: From/To) is disabled and it prints the blank page as second page (completely useless, my customer may think I ...
-5
votes
3answers
270 views
How to make a 3D .STEP model for components? [closed]
Any ideas? I'm really trying to make my own 3D components, I'v read something about solidworks but i havn't seen any tutorial about this topic until now...
8
votes
2answers
669 views
Standard format for custom symbols in schematic drawings?
When drawing a circuit in a schematic editor, most of the time people are going to have to draw their own custom symbols, for example ICs.
What is the standard practice for the way in which pins are ...
0
votes
1answer
108 views
Eagle Cad: Library package appears different when placed on pcb
I placed a device and package on the schematic and board. However, the package appears different on the pcb, and generates DRC 'dimension' errors. The package is a 3-pin sip, Allegro Micro Hall-...
4
votes
1answer
640 views
Eagle via option 1-16 not shown
For this one eagle drawing, I am not seeing the via option for 1-16 layer. I can only put a via connecting layer 1-2 (see attached). If I try to change layer while routing from top to bottom, I get ...
1
vote
2answers
502 views
PTH drill diameter do the IPC take the pin distance in account?
I wonder if the IPC take the Pin distance tolerance in account for the drill diameter? (see p in pic). I can't find any guidelines for it anywhere.
Or is it just so that it's implicitly,common sense ...
0
votes
0answers
4k views
proteus dc voltmeter and ammeter results are not accurate / non existent!
I'm a beginner to Proteus and was just exploring simple circuits and trying out different things on the simulator. I built this simple circuit with a potentiometer and an led and measured current and ...
2
votes
1answer
339 views
Altium VersionControl_RevNumber special string
I have encountered a rather strange problem in Altium Designer 17.1. I am using the special strings VersionControl_RevNumber and VersionControl_ProjFolderRevNumber to keep track of our PCB Revisions ...
0
votes
1answer
80 views
how to go from eagle design to Part list
I am looking for a maintainable, shareable and scalable process to output a complete part list (as in "Part N°XXX from supplier YYY") From an Eagle project, when it seems to only be able to provides a ...
30
votes
6answers
6k views
How were schematics drawn before CAD?
I was looking at the schematic of an old HP power supply I bought. It can be found here, around page 60-61.
This schematic was drawn long before CAD was a tool used by engineers. Things were still ...
1
vote
2answers
367 views
How to add identical pad names to a package
In a schematic you can you use the @ notation to specify multiple pins with identical names for example GND@2. This doesn't seem to work in a package/board. For example an arduino board PCB has ...
1
vote
1answer
301 views
EAGLE tool to LTSpice
I want to use a CadSoft - EAGLE tool model in LTSpice. I can't seem to find a way to do it. I can open the file in LTSpice as a "code" file so I can easily make appropriate changes in it. The file ...
2
votes
2answers
1k views
Solder mask resist on extra large through hole pads
I'm adding extra copper area for more thermal heat on through hole components pads. I now wonder if it's okey to have the solder resist overlapping the edge of this extra large copper area and what ...
2
votes
2answers
638 views
Designators in Altium PCB Libraries
I've noticed that some Altium PCB Libraries contain a designator in a Text field using the .Designator parameter. I've duplicated this in my own libraries, however ...
0
votes
2answers
238 views
Signals between sheets in DipTrace
Given multiple sheets in DipTrace, I am looking to do something like this:
There are a few ways I've found by which I can do something functionally similar - if not identical, - but which are ...
0
votes
1answer
163 views
Correct way in drawing a diagram
I'm an hobbist, so the reason of the silly question.
So I'm drawing with Eagle ( express ) a schematic for a DC motor driver with raspberry. I'm planning to use 2 L293D to drive four motors + another ...
3
votes
1answer
873 views
Eagle CAD pins with same function
I would like to design a tactile switch footprint, where there are clearly two pads and two pins on each side of the switch, but let eagle cad's router know that it can route to either pair of pins. I ...
-4
votes
2answers
200 views
Is it possible to generate an electronic schematic automatically, and are there any tools to do this? [duplicate]
I was wondering if it is possible to automatically generate a schematic from some higher-level description (CPU ==> RAM, etc) of a circuit? And whether there are tools that can do that?
0
votes
1answer
196 views
Mosfet shared diffusion Spice extraction (Magic)
I'm working on a project and try to design a layout using cmos CAD tool Magic. In a part of the project, I connect the nmos transistors in the form of shared diffusion as follows(each square ...
3
votes
3answers
2k views
Is there a functional difference between square, round and octagonal via pads?
The reason why these different shapes exist is probably historical, but I'm interested whether there's any reason today to not only use a single kind of via.
The ones with round pads are the most ...
-1
votes
1answer
122 views
EAGLE - Error when saving Library
After I've installed EAGLE on new OS I've moved all EAGLE files from my backup to main EAGLE directory inside programs folder to recover all my lib/files. All works good but when I save changes on a ...
8
votes
3answers
3k views
Why are DIY PCB components placed at right angles?
I'm learning PCB CAD. I want to know why components seem to be placed at right angles and orthogonal to the PCB (assuming that it's rectangular). Since the traces are secondary to the placement of ...
