Semiconductor

Transistor

I’ve always been intimidated by them, but essentially they are just a Logic Gate!

A transistor is an on/off switch controlled by an electric signal. Transistors the the building blocks of modern day computer circuits.

The Integrated Circuit combines hundred of Transistors into a single chip.

Electronic component that behave in a non-linear/discrete manner. Transistors are combined to form circuits, they are the basis of Logic Gate.

a transistor has

  • A Drain
  • A Source
  • A Gate

The gate controls the flow from the source to the drain. Screen Shot 2022-11-25 at 8.57.14 PM.png

In BLSI?

I never really understood how a transistor works. Good thing Ben Eater has a video teaching it

  • n-type semiconductor

Transistors on CPU

Okay, so now, I understand how a single transistor can be powered. But I don’t see how we can power so many transistors, and all this intricate wiring to power billions of transistors in a SINGLE CPU?

Speaking of which, GPUs also run on transistors?

This is a really good video with really good visualization.

Linus Tech Tips also toured the Intel Fab, which is SUPER insightful

You should also watch Sam Zeloof videos to understand.

Types of Transistor

Ethan Childerhorse taught me this, but there are two types of transistors really.

Thoughts

So logic gates are made from transistors.

These transistors are all powered by some source (like battery). But who controls how these transistors on and off. Is it a chain reaction?

These are actually how the gates are implemented with transistors http://hyperphysics.phy-astr.gsu.edu/hbase/Electronic/trangate.html

So logic gates/transistors combine control inputs. Where do these control inputs come from?

  • In the simplest case, think if you want to use a flip-flop to store data. You input the data you want to store
  • Now, go up a level of abstraction. You write a program that stores the data that you entered from your keyboard. The IO sends data to a microcontroller

Then the question is like, how does a microcontroller work?

Bipolar Junction Transistor (BJT)

Current controlled

This is the type in the Arduino kits

MOSFET Transistor

These are voltage controlled

Old Notes

Transistors Explained by Engineering Mindset Transistors come in different shapes and sizes.

BIpolar and Field effect.

Small electronic compoennts with two main functions,

  1. switch circuits on and off
  2. Amplify signals

Three pins,

Emitter Base Collector

Why do we use transistors?

We can use a switch in a lightbulb and battery circuit.

0.6V to 0.8V for transistor to turn on.

NPN transitor

Conductor vs Insulator vs Semiconductor