Differential pair pad entry

Question

Hi, 
 The differential pair entry into a pad in allegro 23.1 was ortogonal

However, Since I uploaded allegro 25.1 the differential pair entry is different and I'm not able to route it orthogonal to the pad: 
 
 Does anyone know how to change the entry? 
 
 Thank you in advance.

excellon1 · Answer

Hi in your second picture you have DRC's so there may be spacing issues with the trace to pad on the left side. What DRC's are reported ?. 
 There are a couple of methods to route in diff-pairs, Regardless of the etch style, When you route off the pin it should typically look like what you have in the first picture. Since the pins in pic 2 are fairly close try this. click on the pin and route off the pin a short distance then left click to stop routing. Next right click and choose target > route from target and you should see the etch auto start from the other end of the diffpair. Continue routing to join the etch up. Where the etch comes off the pin it should gather the same as each end of the net.

steve · Answer

Have a look at Setup - User Preferences - Route - Connect and padentry_factor. This may help.

steve · Answer

Try clicking on the Next button..... you can also type that into the Smart Search...

excellon1 · Answer

There are many moving parts to the Diff- Pairs, One thing worth trying is the miter factor. If this is too low then your etch may not escape the pin and turn to sharply. 
 So click on your pin to start your diff pair. In the "Options Pane" check to see if the actual miter is at a minimum 2xwidth. You can change that to a higher value to see how the diff-pair responds. If the Miter is set to something like 1xwidth the etch will turn too sharply and not escape the pins as you want. 
 Its also possible to use single trace mode. In that mode you route off the pin a certain distance then left click to stop routing, next right click and uncheck single trace mode. The other pin should route in to match the etch you started. 
 So click on pin both diff-pairs appear. Right click and choose "Single Trace mode" Rote off the pin and left click to stop routing. Right click and uncheck "Single Trace mode" Let us know if it works. 
 More than likely the trouble is related to the miter. A good value for Pad Entry Factor is 75 !

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Differential pair pad entry

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