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Learn electronics by practice

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Re: Learn electronics by practice

#41

Post by rramadass »

_Microft wrote: post #5
max_ wrote: post #3

Earlier quoted context omitted.

What other kinds of "electronics" are there?

Analog electronics [0] uses a continuously variable signal while digital electronics interprets the signal with thresholds that define states like 0 and 1. Here is a simple example: using a few discrete parts, like two transistors (Darlington pair), a LED and resistor, you can create a simple circuit that shows varying brightness of the LED depending on how close you move your hand or an object to an antenna connecte…

> Here is a simple example: using a few discrete parts, like two transistors (Darlington pair), a LED and resistor, you can create a simple circuit that shows varying brightness of the LED depending on how close you move your hand or an object to an antenna connected to one of the transistors (forming a sort of proximity sensor)

Do you have some book/video/etc. recommendations for this "type" of Electrical/Electronics circuit engineering? I only know how to program a MCU :-(

Re: Learn electronics by practice

#42

Post by dragontamer »

dktnj wrote: post #9
max_ wrote: post #3

Earlier quoted context omitted.

What other kinds of "electronics" are there?

Probably the wrong way to look at it. Digital electronics doesn't really exist outside of theoretical spaces. It's all analogue underneath and any experienced digital designer will know that and what the consequences for things like signal integrity, noise immunity and latency.

I mean... Analog electronics doesn't exist either, or for that matter, electronics in general.

All of electronics assumes Kirchhoff's Current Law and Kirchoff's Voltage law, which does not truly exist in reality. Electrons often escape a circuit (see antennas, which throw the voltage / current into a wave that is emitted out of your designs). All wires are antennas, so even the most basic circuit doesn't have all the current return in a loop.

The assumptions of KVL and KCL are just over-simplifications of true physics, Maxwell's equations. Because working with Maxwell's equations directly is too much effort in practice.

--------------

Electronics itself is a huge abstraction upon physics. You could, in theory, calculate all the voltages and currents using Maxwell's equations, except this isn't useful at all.

Similarly: most of "Analog Electronics" uses simplifications as well: OpAmps are often assumed to be ideal (aka: infinite gain), which is good enough in most cases.

Re: Learn electronics by practice

#43

Post by simonbarker87 »

mike50 wrote: post #35
matmann2001 wrote: post #27

Earlier quoted context omitted.

In my experience in a university ECE program, you'd start with understanding the high level properties of transistors, then combining transistors to make AND and OR gates, then XOR and other gates, then MUXes and half/full adders, then flip-flops and eventually into synchronous (clocked) logic. The lab component of such coursework did start with TTL chips but the timing of the coursework was such that you'd have most…

Was it an Electrical Engineering, Electronics Engineering or Electrical Engineering Technology Program? My digital course skipped over transistor level and spent that time on basic FPGA's instead.

Not OP but I did Electrical and Electronic Engineering undergrad and we started with diodes at the materials level, then BJT and FET transistors, then logic gates, flip flops, timers, ALUs and eventually working up to build a Motorola 68K micro controller from mid level components. There was some VHDL and FPGA in the later stages as well from memory.

Re: Learn electronics by practice

#44

Post by SanderNL »

kaishiro wrote: post #24

I opened this thinking I was the target audience - a longtime developer who has always wanted to get into electronics. However, this first paragraph... > In order to present our paradigm in learning electronics, we can take an example of a full adder chip that enables binary addition. Let us use a top-down approach, and look at the datasheet of the TTL (Transistor-Transistor Logic) chip 7483. We will immediately noti…

You are plenty clever.

This is the equivalent of introducing programming by giving a piece of ARM assembly and stating that it is immediately obvious that we are dealing with a merge sort implementation.

I’m not sure why, but I see this often in other domains as well. Math in particular. I guess it’s the curse of knowledge.

Re: Learn electronics by practice

#45

Post by SanderNL »

mike50 wrote: post #34

Someone rewrote a bunch of text books from the 1970s and put them on the internet. Unless you work in IC development you don't need to know how comparators work internally. The logic gate examples are slighly less obsolete (early 1980s). This is yet another joke introduction written by a hobbyist who wants to mess with individual transistors for no purpose. There are no practical applications for these examples and t…

You ever built a computer this way? If nothing else it’s great fun and kind of magical TBH.

Re: Learn electronics by practice

#46

Post by Animats »

kaishiro wrote: post #24

I opened this thinking I was the target audience - a longtime developer who has always wanted to get into electronics. However, this first paragraph... > In order to present our paradigm in learning electronics, we can take an example of a full adder chip that enables binary addition. Let us use a top-down approach, and look at the datasheet of the TTL (Transistor-Transistor Logic) chip 7483. We will immediately noti…

I once took a computer architecture course from the designer of the Burroughs 6700, who had us do a similar exercise. But that was back when people actually built things out of 74xx TTL. Few people do that any more. It would be very unusual to use a 4-bit adder chip today, unless you're deliberately doing retro stuff. And even more unusual to start there. Also, a 4-bit adder, a stateless device, is only useful when surrounded by latches and clocks so that something useful happens.

Here's a real beginner level presentation, from Adafruit.[1] This may be too simplified for some.

The Art of Electronics by Horowitz and Hill is highly recommended, but the original audience was physics grad students who needed to build instrumentation for physics experiments. The order of presentation is good, but it's a big book. Because it mentions current components by part number, the book ages rapidly.

[1] https://learn.adafruit.com/guides/beginner

Re: Learn electronics by practice

#47

Post by Animats »

patmorgan23 wrote: post #14
max_ wrote: post #3

Earlier quoted context omitted.

What other kinds of "electronics" are there?

Analog, Radio and television were both developed before digital electronics was.

Digital systems, using relays, predate analog electronics.

There were relays used for railroad signaling in the 19th century. Union Switch and Signal was formed in 1881. The first active electronic device, the deForest Audion, was developed in 1906.

Re: Learn electronics by practice

#48

Post by tinco »

SanderNL wrote: post #44
kaishiro wrote: post #24

I opened this thinking I was the target audience - a longtime developer who has always wanted to get into electronics. However, this first paragraph... > In order to present our paradigm in learning electronics, we can take an example of a full adder chip that enables binary addition. Let us use a top-down approach, and look at the datasheet of the TTL (Transistor-Transistor Logic) chip 7483. We will immediately noti…

You are plenty clever. This is the equivalent of introducing programming by giving a piece of ARM assembly and stating that it is immediately obvious that we are dealing with a merge sort implementation. I’m not sure why, but I see this often in other domains as well. Math in particular. I guess it’s the curse of knowledge.

Except that when I was in highschool, programming in assembly was not in the curriculum, but designing simple logic circuits was. I am pretty sure we practiced designing a half adder in physics class as part of the electronics chapters.

The bad part of the writing is the assumption that all that technical language and knowledge is stil at the top of your memory when you just picked up this book.

Re: Learn electronics by practice

#49

Post by pfyra »

WalterBright wrote: post #30
dgacmu wrote: post #29

Earlier quoted context omitted.

I think this is mostly poor writing on the part of the author. You being able to "immediately notice" is contingent upon having read the data sheet, which was not linked nor reproduced, but the way it was presented made it seem like the diagram was sufficient. If you were to have read the data sheet, it would have stated up front that the circuit performs four-bit addition. But the page did not facilitate that...

> this is mostly poor writing on the part of the author Indeed. The correct way is: "It is trivially obvious to the most casual observer that the chip performs the addition of two 4-bit binary words"

There should be a "clearly" in there as well as that word by itself is commonly believed to bring a lot of clarity.

Re: Learn electronics by practice

#50

Post by dpwm »

kaishiro wrote: post #24

I opened this thinking I was the target audience - a longtime developer who has always wanted to get into electronics. However, this first paragraph... > In order to present our paradigm in learning electronics, we can take an example of a full adder chip that enables binary addition. Let us use a top-down approach, and look at the datasheet of the TTL (Transistor-Transistor Logic) chip 7483. We will immediately noti…

If you look up a data sheet for any 7483 variant, it is immediately notable: the first lines are something like "4-bit binary full adder" and the description says "…accept two 4-bit binary words" If you skip to the next paragraph, you’ll see they are onto transistors. Ideally the author could show a data sheet, but there may be reasons they can’t.

I found the material that followed to be a clear exposition of the fundamentals – this is as somebody who has tried to learn electronics over the years but nothing ever stuck. This did a better job than anything else at a pace that is about right for me.

But YMMV and I personally relish being in a room full of people who are smarter than me.

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