We need to make sure we can package the IC after the wafer has been diced into individual dies.

A common way of packaging ICs is to connect them to a leadframe by bonding tiny wires between the leads of the leadframe and the pads on the die.

The big bond pads around the outside of the IC often include ESD protection diodes, Input/Output drivers and so on.

This picture shows raven, an IC from Efabless. You can see around the edge there are the big bond pads and the power and ground lines. This structure is called a padring.

The padring used in the Google shuttle is included in Caravel.

Course feedback

If you've got any interest in how the sausage is made you should get on the course and you should dig in and find out more. I mean this was the work of secret witches and wizards in mysterious cloaks casting strange incantations over a cauldron! This was all secret stuff and I love that this project is trying to do to silicon design what the open source community has been trying to do with software for the last 30 years. This feels like the next logical step and I think we'll look back and say well of course you can make your own chips that's just a thing and it will just be obvious and commonplace and I look forward to that.

Jonathan Pallant (digital course)