3.2 What does a processor look like?
So what do these devices that are manufactured in such vast quantities look like? Processors are manufactured as integrated circuits. Essentially they are circuits, around the size of a fingernail, which contain many millions of electronic components manufactured as one very complex circuit. Figure 4(a) shows how a processor manufactured as an integrated circuit is packaged so it can be used as a component in an electronic circuit. The pins of the package are connected to the integrated circuit using gold bonding wire. (Gold is most commonly used, but sometimes aluminium is used instead.) Some of the pins are used to supply the electrical power to the device, while signals are input to and output from the processor via other pins. Figure 4(c) shows the integrated circuit I mentioned in Section 1, the one developed as part of the ENIAC fiftieth anniversary project.
Figure 5 shows the packaged processor assembled with other components on the motherboard of a computer. A motherboard is the major circuit board inside a computer and it holds the processor, the computer bus, the main memory and many other vital components.