active area


active area

[′ak·tiv ′er·ē·ə] (electronics) The area of a metallic rectifier that acts as the rectifying junction and conducts current in the forward direction.

active area

The active area is the top part of the chip where all the action takes place. It contains the layers of transistors, resistors, capacitors and interconnections that make up the circuits and perform the actual computing. Although the thickness of the entire chip is only about 1/30th of an inch, the active area is just a few micrometers. See chip.

Entirely Magical
No man-made object is more incredible than the CPU chip. Today's state-of-the-art CPUs contain billions of transistors, many millions of which are simultaneously switching their state from on to off and off to on every second. In fact, so many transistors are changing at the same time that, in total, there are quadrillions of transistor state changes taking place every second. Think about that number... quadrillions of changes every second! Second after second, minute after minute, hour after hour. See transistor.


A Digital Miracle
When people look at a chip package, they see an object the size of a cracker, but its active area is thinner than a postage stamp. CPU packages can be as large as this or as small as the tip of a lead pencil (see microcontroller). See Boolean logic and chip package.