Connecting multpie pins to a pad? not possible :(

[andrewbarry3000]

Hi all. I am creating a component BAV99T(Q) which requires 2 pins on 1 pad. How does one do this? I will also need to create a spice model as well

CAndrew

[jorge_garcia]

Hi @andrewbarry3000,

I hope you're doing well. So in the symbol you would just draw that internal connection to a single pin. 

So just put 3 pins in the symbol and draw the diodes between them graphically.

Let me know if there's anything else I can do for you.

Best Regards,

[andrewbarry3000]

Hi that would be the easy way out. I need to use a spice model for each of these diodes. I just figured I can copy pad 3 in footprints and name it pad 4 and overlap pad 4 with pad 3. Would this cause an issue? it will appear as there is only 3 pads but 1 is overlapped so i can go ahead with the spice model? Pad 1 is D1 Anode. Pad 3 is D1 Cathode. Pad 4 is D2 Anode. Pad 2 is D2 Cathode or something like that.

I also tried components 2 seperate single diodes but (for the sake of sim purposes) it appears the BAS16T spice model has a figure that was different from its brother BAV99T(Q). 

Thank you for your response

Andrew

[jorge_garcia]

Hello @andrewbarry3000,

From the viewpoint of the schematic and PCB design the process I mentioned above is the correct way. Don't let the spice model dictate what the physical reality of the PCB should be, it's actually the other way around. Your suggested workaround will create problems when routing and even simulating so I don't encourage it.

Do you have the SPICE model for the component you are trying to use? The correct spice model will internally make the connection between the 2 diodes and only expose 3 connections.

Let me know if there's anything else I can do for you.

Best Regards,