I've had some support queries recently regarding the suitability of CircuitStudioCircuitStudio for high speed design so I would like to introduce you to what CircuitStudio offers the PCB designer with regards to individual net length tuning rules and accordions.


Load up CircuitStudio, pick a PCB project and follow along if you wish. The sample board shown has one net (B6) which we are going to concentrate on. Turn on the PCB net information panel, this will show us the routed and unrouted net lengths and make it easy to select a net and highlight it (as seen in the screenshots).



Here's the net routed without an accordion. Clicking on the net name in the list on the left will highlight the net on the PCB and also zoom in to focus on it.



Unroute the connection and then start a new route (R command), hit SHIFT+A to enter accordion mode then TAB to bring up the property dialog.



Click OK and continue to route, an accordion will be placed as you go. Use SHIFT+A to enter and leave accordion mode anytime during routing. You might end up with something that looks like this.



When you exit routing mode the net lengths in the left panel will update to show the new routed (and unrouted) length. Let's now set some min/max length rules to see what happens. Rip up the connection, start routing again and use SHIFT+A, TAB to bring up the accordion dialog. This time click the "Create Rule From Length..." option.



Here we have set the Minimum to 2000mil and the maximum to 4000mil. Click OK to return to the main dialog the select the "From Rules" radio button. Click OK to continue routing.



This time when you route the net with accordion mode enabled the accordion itself does not follow the whole trace, only partially in order to increase the net length slightly. Also highlighted is an overlay that follows the cursor showing the min/max and current routing lengths - very handy.



And finally a handy tip, hit SHIFT+F1 whilst routing in accordion mode and you get a list of available shortcuts. As you can see many are related to the accordion mode and let you adjust parameters without having to keep returning to the main dialog.



Hope these tips have helped and that you all keep enjoying CircuitStudio and producing great boards.