making SMB connector with one signal pin and 4 shielding pins

On 1/11/2011 6:41 AM, Georg Fantner wrote:

Hi,

 

I've been trying to find a way to make a library part for a SMB

connector which does not automatically connect all the 4 pins of the

shielding to the board ground, but still connects all 4 pins together. I

need this because I have an SMB input that goes into a differential

amplifier, so I don't want to die the SMB shield to ground. The closest

I've gotten was by naming the 4 shielding pins something different than

"GND" but then it still connects these pins automatically for all

instances of the part in the design. Does anybody know how to do this?

 

Many thanks!

-Geor

Have you set the "direction" of all the pins to "passive"? You may have

run into eagle's "implicit net" feature which is made to make power

supply connections to IC's invisible on the schematic. Pin directions of

"power" or "supply" are used to implement this feature. see help pin for

a little more info. now you know why it is a bad idea... there is a way

to turn it off in v5 I believe.

I have a device with two variants (horizontal and vertical package

orientation). When in vertical orientation, the central ground pad

cannot (of course) be connected since it is not in contact with the

board. For this vertical variant, I cannot connect the symbol ground pin

(VSS@2) to a corresponding pad since there is no pad. Therefore, the

device cannot be added to a board (Eagle creates an error).

What can I do? The horizontal variant should have the pad connected,

whereas the vertical variant cannot have the pad connected.

It seems to me that this will be a common issue with parts available in

multiple packages with differing numbers of pads - some variants will

have signals (pins) duplicated on multiple pads, whereas others will not.

Thanks,

Erik

Why did you post your question as a reply to an older one, and then

changed the subject? Please start a new thread if you have a new

question. Thanks.

Erik Blake schrieb:

I have a device with two variants (horizontal and vertical package

orientation). When in vertical orientation, the central ground pad

cannot (of course) be connected since it is not in contact with the

board. For this vertical variant, I cannot connect the symbol ground pin

(VSS@2) to a corresponding pad since there is no pad. Therefore, the

device cannot be added to a board (Eagle creates an error).

 

What can I do? The horizontal variant should have the pad connected,

whereas the vertical variant cannot have the pad connected.

You need to create two different symbols - and two different devices.

It seems to me that this will be a common issue with parts available in

multiple packages with differing numbers of pads - some variants will

have signals (pins) duplicated on multiple pads, whereas others will not.

Yes, it's a common issue which comes up rather often. There is still no

solution, though we have provided some suggestions about how that could

be implemented.

Tilmann