The wire's z-profile is defined using a model with parameters. While Artwork has developed some very sophisticated user-defined models, we are not going to use those at present - instead we are going to use two very old models developed by JEDEC - the JEDEC 3 point wire model and the JEDEC 4 point wire model.

Jedec 3 Point Wire Model

The JEDEC 3 point wire model requires just two parameters - h1, the height that the wire rises from the die pad and L1 the distance it travels horizontally before beginning a straight line descent to the package finger pad.

illustration of JEDEC 3 point model

The three point model works well for relatively short wires. The illustration is not to scale as h1 and L1 are exaggerated for clarity.

Jedec 4 Point Wire Model

Longer wires generally have a bit of arc in them much like the arch of a bridge -- this helps to reduce the wire sag that might result in a short circuit. The JEDEC 4 point model has additional parameters that enable the user to approximate an arc as shown in the illustration below:

illustration of JEDEC 4 point model

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