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'''IMPORTANT NOTE (until V20.5.0.23):'''
Differential Pairs can be placed only between signals which have exactly '''two''' connection pads. If a signal has more than two pads to connect, it is not a pair anymore and a differential pair routing is refused. A message flashes accordingly. So please connect only signals with two connections as differential pair. If pads to connect follow, the only way is to delete these packages from the layout for a while, do the differential pair routing and later insert them again in order to route them by hand.<br><br><br>


[[image:diffpairs1_e.png]]<br>Image: The main menu "Settings"<br><br>
[[image:diffpairs1_e.png]]<br>Image: The main menu "Settings"<br><br>
In order to place differential pairs for [http://en.wikipedia.org/wiki/Differential_signaling Differential signaling] it is clever to establish a signal class first. It is to determine minimum track width and minimum spacing between different signals.<br>
In order to place differential pairs for [http://en.wikipedia.org/wiki/Differential_signaling Differential signaling] it is clever to establish a signal class first. It is to determine minimum track width and minimum spacing between different signals. Later we will use this class for our differential pairs.<br><br>
 
[[image:diffpairs2_e.png]]<br>Image: The dialog "Edit signal classes"<br><br><br>
 
In our example we create the new signal class ''DiffPairsUSB'' with minimum values of 0,5mm und 0,2mm for track width and track spacing. After having imported two components to the schematic we change over to the mode ''Place wire [2]''    [[image: placewire_small.png]]  Now we press keyboard key [o] for <u>O</u>ptions. In the opening dialog we select our new net class (=signal class), so that the tracks in the layout later will achieve the properties which we have determined here.


[[image:diffpairs2_e.png]]<br>Image: The dialog  "Signalklassen verwalten"<br><br><br>


In unserem Beispiel erschaffen wir die Signalklasse ''DiffPairsUSB'' mit Mindestwerten von 0,5mm und 0,2mm für Leiterbahnbreite und Leiterbahnabstand. Nachdem wir zwei NE555 Bausteine in den Schaltplan herein geholt haben, wechseln wir in den Modus "Signal verlegen" und drücken die Tastaturtaste [o] für <u>O</u>ptionen. Im sich öffnenden Dialog wählen wir die gerade erschaffene Netzklasse (= Signalklasse) aus, damit die Leiterbahnen im Layout später die gewünschte Gestalt erhalten.
[[image:diffpairs3.png]]<br>Image: The dialog Signal Wire Options<br><br>




[[image:diffpairs3.png]]<br>Image: Der Dialog Signalbahn-Optionen.<br><br>


Im Dialog "Signalbahn-Optionen" wählen wir die Netzklasse aus, deren Eigenschaften wir für die Leiterbahnen vorgesehen haben, die Differential Pairs werden sollen.<br>
[[image:diffpairs4.png]]<br>Image: Now we connect the pins using the "Place wire [2]" mode.<br><br><br>


[[image:diffpairs4.png]]<br>Image: Jetzt schließen wir die gewünschten Pins im Schaltplan an.<br><br><br>
[[image:diffpairs5_e.png]]<br>Image: Change to the layout view and import the packages to the layout. <br><br><br>Now we choose menu option: "Settings/Edit Differential Pairs". From the right we select the pair of signals we like to treat as such. Using the arrow in the center of the dialog we shift them to the left in order to activate them for differential signaling.<br><br><br>


[[image:diffpairs5.png]]<br>Image: Nachdem wir die Gehäuse ins layout herein geholt haben, wählen wir den Menüpunkt: "WEinstellungen/Differential Pairs verwalten". Rechts wählen wir dann das gewünschte Signalpaar aus und bringen es nit der Pfeiltaste auf die Linke Seite des Dialogfensters.<br><br><br>
[[image:diffpairs6_e.png]]<br>Image: The signals OUT and |RES are going to be differential pairs.<br><br><br>


[[image:diffpairs6.png]]<br>Image: Differential pairs werden die Signalse: OUT und |RES. <br><br><br>
[[image:diffpairs7.png]]<br>Image: Now use the extension of the icon "Draw track [2]" and select the button to "Draw a differential pair".<br><br><br>


[[image:diffpairs7.png]]<br>Image: In der Erweiterung der "Leiterbahn verlegen" - Ikone wählen wir den Modus "Differential Pair verlegen."<br><br><br>
[[image:diffpairs8.png]]<br>Image of the pointer in "Differential pair" - mode.<br><br><br>


[[image:diffpairs8.png]]<br>Image: Mauszeiger im "Differential Pair" - Modus. <br><br><br>
[[image:diffpairs9.png]]<br>Image: Now we place the tracks as a parallel running pair segment by segment. The track width and the track spacing are determined by the signal class in use, see above.<br><br><br>


[[image:diffpairs9.png]]<br>Image: Jetzt verlegt man Segment für Segment die beiden Signale als parallel verlaufendes Doppelpack. Leiterbahnbreite und -mindestabstand sind in der Signalklasse bestimmt, siehe oben. <br><br><br>
[[image:Diffpairs10_e.png]]<br>Image: A short distance in front of the connecting pads we cancel the action and give TARGET 3001! the command not to fulfill the connection automatically. We do the final connecting by hand.<br><br><br>


[[image:diffpairs10.png]]<br>Image: Kurz vor dem Anschluss an die Ziel-Pads, bricht man den Vorgang ab und weist TARGET an, die Bahnen NICHT fertig anzuschließen.<br><br><br>
[[image:diffpairs11.png]]<br>Image: This is the way our differential Pair might look like. The right one is still highlighted, that's the reason why it appears in yellow.<br><br><br>


[[image:diffpairs11.png]]<br>Image: So könnte der parallel verlaufende Leiterzug zweier unterschiedlicher Signale letzlich aussehen.<br><br><br>
Since version V20.5.0.73 also differential pairs can be [https://server.ibfriedrich.com/wiki/ibfwikien/?title=Meander+a+track meandered] to gain certen lenghts:<br><br><br>
[[Image:Meander7_en.jpg]]<br>Image: Meander with Differential Pairs<br><br><br>




[[de:Differential Pairs]][[fr:Differential Pairs]]
[[de:Differential Pairs]][[fr:Differential Pairs]]

Latest revision as of 08:08, 25 January 2020

IMPORTANT NOTE (until V20.5.0.23):

Differential Pairs can be placed only between signals which have exactly two connection pads. If a signal has more than two pads to connect, it is not a pair anymore and a differential pair routing is refused. A message flashes accordingly. So please connect only signals with two connections as differential pair. If pads to connect follow, the only way is to delete these packages from the layout for a while, do the differential pair routing and later insert them again in order to route them by hand.




Image: The main menu "Settings"

In order to place differential pairs for Differential signaling it is clever to establish a signal class first. It is to determine minimum track width and minimum spacing between different signals. Later we will use this class for our differential pairs.


Image: The dialog "Edit signal classes"


In our example we create the new signal class DiffPairsUSB with minimum values of 0,5mm und 0,2mm for track width and track spacing. After having imported two components to the schematic we change over to the mode Place wire [2] Now we press keyboard key [o] for Options. In the opening dialog we select our new net class (=signal class), so that the tracks in the layout later will achieve the properties which we have determined here.



Image: The dialog Signal Wire Options



Image: Now we connect the pins using the "Place wire [2]" mode.



Image: Change to the layout view and import the packages to the layout.


Now we choose menu option: "Settings/Edit Differential Pairs". From the right we select the pair of signals we like to treat as such. Using the arrow in the center of the dialog we shift them to the left in order to activate them for differential signaling.



Image: The signals OUT and |RES are going to be differential pairs.



Image: Now use the extension of the icon "Draw track [2]" and select the button to "Draw a differential pair".



Image of the pointer in "Differential pair" - mode.



Image: Now we place the tracks as a parallel running pair segment by segment. The track width and the track spacing are determined by the signal class in use, see above.



Image: A short distance in front of the connecting pads we cancel the action and give TARGET 3001! the command not to fulfill the connection automatically. We do the final connecting by hand.



Image: This is the way our differential Pair might look like. The right one is still highlighted, that's the reason why it appears in yellow.


Since version V20.5.0.73 also differential pairs can be meandered to gain certen lenghts:



Image: Meander with Differential Pairs