Don't Connect/Route Power Pin

Thanks for the replies and tips!

My problem is with Auto Router. There are some headers which provide +5V and +3V3 to my shield, but those +5V are begin connected to each other, even when they are an Output, what wouldn't be necessary.

For example: There are the +5V in ICSP header and +5V in Power Header, they don't need to be connected to each other, as they are the same Output. This cause a wast in Auto Router as it routes the unecessary wire.

Is there a way to make it don't waste Auto-Routing those wires?

Thanks for the replies and tips!

My problem is with Auto Router. There are some headers which provide +5V and +3V3 to my shield, but those +5V are begin connected to each other, even when they are an Output, what wouldn't be necessary.

For example: There are the +5V in ICSP header and +5V in Power Header, they don't need to be connected to each other, as they are the same Output. This cause a wast in Auto Router as it routes the unecessary wire.

Is there a way to make it don't waste Auto-Routing those wires?

On 10/09/15 03:12, Giovanni Campaner wrote:

For example: There are the +5V in ICSP header and +5V in Power Header,

they don't need to be connected to each other, as they are the same

Output. This cause a wast in Auto Router as it routes the unecessary

wire.

Really? You have two pins that you have explicitly placed ON THE SAME

NET in the schematic, thus telling Eagle that they need to be connected,

and you're complaining that it tries to connect them?

If they shouldn't be connected then they can't be the same signal and

you need to not have them connected on the schematic.

If they are the same signal and should be connected then you WANT the

autorouter to connect them.

If the power header and ICSP header both have pins for the 5V supply,

and it's the same 5V supply, then both pins need to be connected to the

5V supply and thus to each other for the board to be correct.

If you don't like the particular route that the autorouter lays out then

do that routing by hand. Just don't blame the tool for doing what you

tell it to.

autodeskguest  wrote:

Really? You have two pins that you have explicitly placed ON THE SAME

NET in the schematic, thus telling Eagle that they need to be connected,

and you're complaining that it tries to connect them?

 

If they shouldn't be connected then they can't be the same signal and

you need to not have them connected on the schematic.

 

If they are the same signal and should be connected then you WANT the

autorouter to connect them.

 

If the power header and ICSP header both have pins for the 5V supply,

and it's the same 5V supply, then both pins need to be connected to the

5V supply and thus to each other for the board to be correct.

 

If you don't like the particular route that the autorouter lays out then

do that routing by hand. Just don't blame the tool for doing what you

tell it to.

I am aware this is an old thread but I think the subject needs additional explanation.

The problem is when using a device describing some additional PCB that could be placed onto the PCB that is being designed. For example, I've made a device for Arduino Pro Mini 18x32 mm board which can be placed into the schematics as any other component (e.g. resistor or transistor). The problem which original poster is reffering to is the following:

In the described case where the component placed into desigh has multiple pins connected internally, there are multiple situationy when we do not want or even must not to connect these pins once again with PCB traces. For example Pro Mini board has RAW input which goes to the voltage regulator and it has two Vcc ouputs to power some other 5 V device with the same voltage as the µC. However, these pins can be used as inputs as well. If we do not connect voltage to the RAW input (we do not use the voltage regulator) then we can connect 5 V to Vcc pin to power the µC directly. Furthermore, I have a design where the µC is powering the light sensor via output pin (to conserve the battery during sleep) and in that case we don not want anything at all to be connected to Vcc pins. We do not want to connect both internally connected Vcc pins with the traces which will prevent efficien routing of other traces we need.

The second Vcc on that board is just so it is more convenient to connect the programing cable, the secong Vcc pin is not because of the same reason µC itself has more supply pins!! µC has more power supply pins because of the current cosideriations but Mini Pro board has 2 Vcc and 5 GND pins just because of the convenience to connect more devices. When we solder such a board to our PCB we don't care to which of the Vcc of GND pins will some trace be connected. But we do care if Eagle insists that we draw the traces to connect the internally already connected pins once again - and to ruin our routing!! The traces between multiple Vcc and multiple GND pins are already routed on our board that is soldered onto the design, we do not want to connect those traces again because in our design.

The original poster was right when he was annoyed by Eagle's insisting to connect already connected traces once again. That is (was?) well known Eagle's problem of which the authors were aware - so they even implemented the solution.