Internal connections: Difference between revisions
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For the fact that the decision for the load capacity in most cases is not made by the designer of the part, the user of this part needs to confirm the connection. In the layout just draw two normal pads not touching each other. In the schematic create two pins as well but place them exactly superposed to each other: | For the fact that the decision for the load capacity in most cases is not made by the designer of the part, the user of this part needs to confirm the connection. In the layout just draw two normal pads not touching each other. In the schematic create two pins as well but place them exactly superposed to each other: | ||
[[Image: | [[Image: PinsUebereinander_e.jpg]] | ||
The pin numbers 1+2 are displayed together by TARGET automatically later: | The pin numbers 1+2 are displayed together by TARGET automatically later: | ||
[[Image: | [[Image: PinsUebereinander2_e.jpg]] | ||
In this case two pins showing the length of zero are used, the pin numbers have been deleted. If several poles in a part are wanted several connections are superposed to each other: 1+2, 3+4, 5+6 ... If more than 2 pins represent one pole in a connector then the pins are combined as three: 1+2+3, 4+5+6, ... Such a combination in TARGET is called "cluster". | In this case two pins showing the length of zero are used, the pin numbers have been deleted. If several poles in a part are wanted several connections are superposed to each other: 1+2, 3+4, 5+6 ... If more than 2 pins represent one pole in a connector then the pins are combined as three: 1+2+3, 4+5+6, ... Such a combination in TARGET is called "cluster". | ||
Revision as of 17:23, 4 March 2013
In a component several pins/pads might internally be connected in order to have electrical load capacity. So they can be used like a brigde. For example in a connector one terminal can be connected to several pads:
Both connections are needed to give mechanical stability. If the current load is only low the internal connection might be used as a bridge. Route close to one of the pads and continue routing with the other. The gap in between can be used routing through to it. But if the electrical load capacity is high it might be necessary to connect both pins by a current leading piece of track.
For the fact that the decision for the load capacity in most cases is not made by the designer of the part, the user of this part needs to confirm the connection. In the layout just draw two normal pads not touching each other. In the schematic create two pins as well but place them exactly superposed to each other:
The pin numbers 1+2 are displayed together by TARGET automatically later:
In this case two pins showing the length of zero are used, the pin numbers have been deleted. If several poles in a part are wanted several connections are superposed to each other: 1+2, 3+4, 5+6 ... If more than 2 pins represent one pole in a connector then the pins are combined as three: 1+2+3, 4+5+6, ... Such a combination in TARGET is called "cluster".
In packages already placed click M11 upon the handle cross. While the dialog "Change packages" flashes, select button [Internal connection]. Now the pins belonging to each other can be combined to clusters. If the pins in the schematic already are superposed to each other correctly then one just can confirm the proposal. In consequence TARGET combines all clusters automatically.
Other CAD systems (e.g. Eagle) require the decision whether pins are internally connected already when drawing the part. The properties "all" and "any" are used in a "Connect" context. "all" for: all pins need to be connected, "any" for: it is sufficient to connect any pin. This leads to problems because the designer of the part can not know, how heavy the electical load later will be. A push button with one pin and a 2x2 connection in a motor control sure won't lead the complete motor current through its small package just only because 2 pins are joint together to GND:
