[SOLVED] the best way reading and understanding a electronic circuit?

the best way reading and understanding a large electronic circuit?

hi,in programming we have a skill,that is a person can read a large source and it can predict function and methods and object the source........
in electronic i saw some large electronic circuit.
my question is :
what the best way reading large electronic circuit?
i want to achieve this skill.
thanks for reply

LIke reading music, you have to start with small circuits to recognize them in a big schematic like this.
This takes me a few minutes to read any schematic after yrs of good experience and lots of motivation to read.
broken link removed
You can read design articles in trade magazine that describe how they work until you understand. In the old days we read a bookshelf full of analog and digital IC application books from National Semi ( now TI).

You can start with understanding how a transistor can be biased and the properties of input and output impedance, and how to recognize transistor switches, so that you know all the standard configurations... cold...

Its like reading the written word, or a map (or a software flow chart).
You need to understand individual words and map symbols.

And there are rules such as reading a page left to right and top to bottom, and North is always up up in any map. Flow charts generally flow downwards, etc..

When you can recognise those things, larger functional patterns start to emerge, like sentences or recognisable topographical map features, or... that is an amplifier, or an oscillator, or a voltage regulator.

Laying out a good clear circuit diagram that is recognisable and clearly understood is a real skill.

I have seen flow charts that look like a bowl of spaghetti, and circuit diagrams that can be completely baffling even to an expert.

A good schematic diagram is a pleasure to read. I am not an expert, but I can make out whether the schematic is nicely drawn. Sometimes the young engineers will draw a 555 timer circuit in such a convoluted way that you (no offense, it means me) will need a pen and paper. Sometimes lots of paper. Sometimes I take 4-5 printouts of the same schematic and try to understand the basic building blocks.

Even a complex circuit diagram can be decomposed into basic functional blocks. With some experience (that is my catch phrase) you will be able to guess the specific function one particular block is supposed to do. If you can figure out most of the blocks this way, you are on the right track and you are going to the right path to success.

Look at the circuit with a fuzzy eye; do not focus on the resistors and capacitors but try to identify the inputs and outputs and what it is supposed to do and how it does that. That is what I meant when I said that a neatly drawn schematic is a pleasure to read. But many young engineers are not Maupassant and you need to devote time or give up.

I hope I have not offended anyone. Apologies in advance.

thanks @SunnySkyguy @Warpspeed @c_mitra
for starting it's like decoding .:fight: or perhaps read a Alien book;
i soon will start practice.
good luck

So that is how real schematics looks like...

I have a question which is not really relationed with this thread but relationed to the schematic.

Schematic that works in theoretically analysis may not work in real life, what does an engineer to get it done before implement it ? The one who did that schematic, or a final project is sure 100% that implemented will work, but how does he achieve that ? There is when experience comes in right ?

HP had a graphics engine with Rubber band mode in the late 70's or early 80's that made moving objects in drawing because it moved other objects in a nearby area according to constraints so that drawing schematics or board layouts easier with auto-routing.

My draftsman would insist on Size D or E drawings saying this was the military method so microfiche would be legible. I vetoed him and got him to use size C for complex designs with smaller blank space yet extra text.

He added REFDES not used and LAST RefDes in a table.

But my all time favorite schematics were from Tektronix. But Japanese schematics were pretty great too. ( Hitachi, Fujitsu, Toshiba)

CataM said:

Schematic that works in theoretically analysis may not work in real life, what does an engineer to get it done before implement it ? The one who did that schematic, or a final project is sure 100% that implemented will work, but how does he achieve that ?

Click to expand...

I do not know all the reasons why a schematic that works in theoretical simulation may not work in real life but one rather simple aspect is component placements. There are so many constrains in real life (you must have power transistors close by or potentiometers near the edge of the board or the power supply connection at one end or the ground plane should be relatively continuous or the oscillator should be near the microprocessor ... the list is endless.

One thing is sure: as far as possible, cluster the functional blocks as a basic unit and most likely the design will work.