Where to read about common solutions and good design practices? - Page 1
Forum section: electronics / beginners

author: jammasterz
author_rank: Newbie
timestamp: October 15, 2014, 10:08:12 pm
content: Hello. I'm studying electrical engineering, I'm currently in my second year(began a few months ago) and we've already gone through the majority of Hambleys Electrical Engineering: Principles & Applications, and we covered the basics. However, when watching videos like the tear-down tuesdays like this one:I find that i don't understand a single word Dave is saying when he analyses the circuits. I understand that there are some very design-specific solutions for oscilloscopes and other things, but i think that i should be able to recognize at least one thing per video.For example, I'm always very confused by the use of capacitors. They are used all over the circuit boards for some kind of voltage protection mechanisms or pull-up/down, whatever that means, and a ton of other places where they completely don't make any sense to me.I am sure that we are eventually get there during my courses, but I really don't want to wait, and also I don't want to be held back by the limited time my school has to teach me about electronics. I'd like to be designing some very simple circuits already, but when i decide to do something and search some info about the topic, they give me a perfect solution that can handle every possible scenario and they don't explain what is happening and why it is designed the way it is. And also, those bloody capacitors are everywhere and their function is never explained.So my question is, where can I start to learn about some commonly used electronics so that i build some kind of ground to, eventually understanding the tear-down of circuits and also be able to build some circuits that are more than just simple basics?

author: AG6QR
author_rank: Frequent Contributor
timestamp: October 15, 2014, 10:32:57 pm
content: The Art of Electronics, by Horowitz and Hill is a popular book in no small part because it is full of a lot of practical examples, with explanations of why components were chosen. It's a bit dated now (a new edition has been right around the corner for quite a few years now), but still pretty good. It's a bit light on theory, but not completely theory-free. It has a lot of practical examples that see fairly widespread common use. It is particularly geared toward scientific instrumentation and measurement circuits, but there are a lot of other general circuits described.Oh, and those bloody capacitors are generally used where the designer wants something to present a low impedance to high frequencies, while presenting a high impedance to low frequencies. But it's hard to be more specific without a particular example.You should definitely be asking your instructors about some of the issues you've brought up.

author: Tandy
author_rank: Frequent Contributor
timestamp: October 16, 2014, 05:13:50 pm
content: Quote from: jammasterz on October 15, 2014, 10:08:12 pmCapacitors are used for many purposes but you will find that virtually every circuit is littered with capacitors used for decoupling. While a circuit is operating the power requirements will vary causing different loading on the supply voltage. A decoupling capacitor is placed as close to each device (usually an IC) that requires a stable power supply. The capacitor smooths out variations in the supply voltage and are particularly important in high speed digital circuits and sensitive analogue circuits like an oscilloscope where small variations in the supply will cause havoc with your readings.Pull-up/Pull-down resistors are used extensively in digital electronics to hold a default state. So an input pin on an IC when not connected to anything is in a floating state, it means that it can switch between sensing high and low for no apparent reason. Often simply because a nearby input has changes state or even because moving your hand over it has induced a static charge. To prevent this you tie the input to the ground or +ve rail so with a relatively high value resistor so that input stays in that state until you supply a signal that will switch it.PS Sorry if I an teaching your grandmother to suck eggs but because this is posted in the beginner section I am assuming you don't already know this stuff.