Symbol Builder

Like all PCB design tools, APD/Allegro uses symbol/pin/netlist as its basic structure. Symbols have pins and the netlist defines how the pins are interconnected. Therefore to move our data to APD requires that we create a mininmum of two symbols - one for our die and one for our package. Of course, if we have two die in a package then we would have three symbols.

We need a mininmum of two symbols - a die symbol and a package symbol

Preparing your Data

To run the symbol builder you will need:

• to have drawn your pins/pads as either zero width closed polylines (for die pads) or as circles or donuts (for BGA substrates.)

• to have drawn your symbol outline as a zero width closed polyline. It need not be rectangular but it must not self intersect and it must completely contain the pads of the symbol.

• If you have text to label nets or pin numbers, the number of text labels must match exactly the number of pins.

Symbol pads with net labels