Monday, July 27, 2015

Altium Designer 15 000 000 codelines

Embarcadero likes mentioning Altimum Designer . . .

'via Blog this'

NPTH (Non-Plated Thru Holes)

When creating a Non-Plated Hole such as a Tooling Hole if you forget to uncheck the Plated option you will most likely get a technical inquiry from your fabricator.

I wish there was a design rule check under the Manufacturing Rules to catch this mistake.


As shown below the pad and hole are set to the same size to create a NPTH. However the user forgot to uncheck the plated option.

To find a NPTH that is incorrectly checked as Plated you can use this PCB Filter:

(PadIsPlated = 'True') And ((HoleDiameter >= PadXSize_AllLayers ) OR (HoleDiameter >= PadYSize_AllLayers))


Copper Clearance Rule (Standard is 10mil)




Plane Clearance Rule



















For Non Plated Holes (if Plated is unchecked) you can use:

(HoleDiameter > 0) And (PadIsPlated = 'False') 

For both Plated or Non Plated Holes use:

((HoleDiameter >= PadXSize_AllLayers ) OR (HoleDiameter >= PadYSize_AllLayers))


Soldermask Expansion (Standard is 5mil from Hole Edge)



If the Soldermask and Copper clearances are both 10mil.  The 10mil copper clearance is good for the internal layers, but what about the outer layers ?

To prevent having a NPTH with exposed metal on the outer layers you need to consider the layer registration tolerances.

That's It !


Sunday, July 19, 2015

Schematic Checks

Altium has some clever features for checking schematics.

If you hover the mouse cursor over a net the schematic insight window will be displayed. 

Also selecting a net and Alt+DoubleClick will also enable the schematic insight view.

The schematic design insight window will highlight all instances of the same net on the current page.




























Selecting a net and Alt+SingleClick will highlight and zoom to where the net is used on the current sheet.

Move the mouse to the sheets displayed in lower to part of the panel to review where the selected net is used in the design. 

Left Click on one of the displayed sheets to jump to the selected sheet.

Tip: Hold down the ALT key use double clicks when selecting the Net and single clicks on the sheets listed in the insight view.

That's It !

Saturday, July 18, 2015

When and How to Upsize Microsoft Access Databases to SQL Server

This article by FMS discusses Microsoft Access and SQL databases.

When and How to Upsize Microsoft Access Databases to SQL Server:


As pointed out in the article 85% of all Access databases do not need to be up sized.

Most companies only have a few seats (licenses) for their CAD tools, so the number of concurrent users is limited.

An Access database is an excellent choice for small groups with 20 or fewer users.  

Access can be used with Altium's DBLIB or SVNDBLIB to create a database solution for CAD libraries.


Database libraries have several benefits compared to primitive *.SCHLIB and *.PCBLIB libraries. New parts can be rapidly added to the database and existing parts are easy to maintain.


Using the link below you can download a turnkey Access / Altium DBLIB CAD library. 


The download includes a optional Access Frontend application.

A Frontend application is not required to use a DBLib database. Parametric data, symbols and footprints can be added, deleted or edited using Altium's DBLIB interface. 


However, a well designed Frontend application like the one found in Parts can greatly simplify maintaining your database library.

Link to Parts: Altium DBLib library created using Microsoft Access

Friday, July 3, 2015

Short Circuit Rules

DRC's for Short Circuits.

Short Circuits violations can include unused pins of a fanned out BGA.

Or custom footprints that have two primitives with the same pin number.





















Example Datasheet for the QFN shown above suggested using chamfered pads for the corner pins.


Two primitives were used to create chamfered pads, a top layer pad and a region.

Pads that are made up two or more primitives can cause Short Circuit DRCs if the pads have no nets assigned.






















The solution is to create a Short Circuit rules to allow primitives with no assigned nets to overlap, using 'Not InAnyNet' 


Allow all No Nets to short together.





















This same technique can be used to allow BGAs to be fanned out and pass the DRC checks for short circuits when the pins don't have assigned nets (No Nets).

For a BGA with unused fanned out connections.




















Allow for overlapping primitives in the same part (not fanned out)
 

That's It !

Wednesday, July 1, 2015

IPC-2581 Consortium - IPC-2581 Free Viewers

IPC-2581 Consortium - IPC-2581 Free Viewers:



As of July 7, 2015 Altium doesn't not have a test case listed with the IPC-2581 Consortium.

I created a small test board using  AD15.1.13.  Then I used Vu2581 to examine the fabrication data. 

I found problems with slots, pads and copper keep outs.

For now it looks like I should only use Gerber outputs from Altium.

That's It !