Why are circuits on boards?

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You know those tech chips (which might not even be chips, but to my uneducated eye look like chips).

In: Technology

Before circuit boards were a thing, designers had to scramble wires together in a big ugly mess. I don’t have all the details of this organization, but imagine a bunch of tangled up wires, capacitors, etc. Circuit boards not only rid of those messy wires, but they’re super compact, which allowed computers back then to shrink down (along with other inventions like the silicon transistor).

Edit: [I found the image I was looking for.](https://rsdacademy.net/textbooks/AnalogCircuits/Part7/PageSetup.php?Page=53&FileName=PrintedCircuitBoards)

Edit2: With Circuit boards came cheaper computers, which meant they could be mass produced and sold to consumers. Paving the way for today’s computers and even the Internet and the www.

All the branches were taken?

Seriously tho, because it’s easy to design in 2d (draw by hand) and mass produce with minimal waste and effort.

Also it’s far more durable and safe than wiring.

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Because it’s way easier to manufacture this way, and therefore nearly all modern parts are designed to be put on printed circuit boards.

That wasn’t always the case, up to the 1950s point-to-point wiring was common.

It looked like this:
https://commons.m.wikimedia.org/wiki/File:Motorolagoldenviewchassis.jpg#mw-jump-to-license

This is basically impossible to automate, and was done on long assembly lines by (typically) women. In those times, labor was cheap and parts were expensive, so this was economically viable. It was prone to faults though, it’s not uncommon at all for collectors of vintage gear to find connections not ever been soldered. They just barely had contact to work on the testing station.

Then came printed circuit boards. The start out as a copper-clad board and all the copper not needed for connections is etched away in a quite complicated process, which I will not explain here.

They started to be used in 1930s, but really became mainstream in the early 1960s. The early board were still populated (parts were stuck through holes) by hand, but already soldered automatically by moving them over a bath with molten solder (wave soldering, still in use today).

From the 1980s onwards, even the placement of components was done by robots and then the whole board is put in a special oven to melt the soldering paste which was put on before the parts. You get a finished board in minutes, with a precision not possible by hand.

Each chip serves a specific purpose

There are little timer chips and little memory chips and little controller chips that let you interface with them and little power chips that give you the right power for the other chips. In theory you could make a single chip that integrates the functions of all the other chips but it would only do a single thing. By having chips with dedicated functions, if you need a timer chip you buy one of them and put it on your board, and since they’re making billions of them for all sorts of applications each chip is cheap

The board itself serves to connect the little legs on all the little chips so that power goes where it needs to and data goes to the right places. We used to solder individual wires to components which works fine when your component is relatively large and there are a few wires per part but doesn’t work nearly as well when your 13mm x 13mm chip has over 200 connection points on the bottom of it.

Using circuit boards allows us to use high precision machines to place the parts down onto the pads and they can work with some really really tiny parts (0.4mm x 0.2mm) and they can put down tens of thousands of parts per hour. Building modern phones at all wouldn’t be possible with circuit boards, and building small phones cheaply would be impossible without the fancy machines

Circuits are the equivalent of wire where electricity passes through. They were then flatten in circuit version without the insulation and all that, the board is just what is used to hold that. It was made of wood initially, but because of all the heat electricity can produce it evolved to material that are a lot more heat resistant.

What else would you do?