1 Reply Latest reply on Jul 21, 2016 10:05 AM by v.placier@wanadoo.fr

    Thermal area for single pin net

    sdonaldson

      I'm using PADS 9.5.  I have a DDPAK with an isolated tab that needs some copper on the board for a heat sink.  This is a single pin net, so it's not named/listed in the netlist to assign a copper plane area.

       

      I currently have it as a flooded plane area, then drew my own thermals from the pad to connect to the plane.

       

      Another option would be to have a "heatsink" component on the schematic and make the footprint a test point or dot or something.  This requires the schematic symbol to be updated to add the tab pin.

       

      Are there any better options?

        • 1. Re: Thermal area for single pin net
          v.placier@wanadoo.fr

          Hello,

          Make sure the NET ("gnd","vcc",or "my_special_net") exist at first in the schematic cause "signal pin" need to be connected to an existing net.

          I think the signals pins should appears in the netlist,otherwise they can't exist when transfered to PCB.

          Once the pin of the D2PAK is really connected to a net you will be able to create a local copperpoor and connect it to the thermal pad

          An other solution could consist to define thermal tab of the D2PACK as "GATE-A pin" ,connect the pin in the schematic and go.

          In any case,the pin and the signal must be present in the netlist (or added later in the PCB by ECO mode) to exist in the PCB when transfed to generate a connected plane or copper aera.

          May be others solutions exist (?)

          Vincent.