Electronic Circuit Traceout

Kindly suggest me any technique.
Patience!
Start with the power supply and + - rails.
Generally I'd rather design my own circuit, at least you have a chance of fault finding it if you design it yourself.
Del

any photos etc ?

Have you contacted manufacturers ?

Did you mean PULSE or PULS?

by seeing it? I doubt it. especially if it is multilayer. no. but it would depend on the complexity.

You can however trace it (board only) with an ohmmeter... or you can build a test bed with spring-pins, and program a microprocessor to strobe the pins sequentially, and map all the paths that way, by 'listening' on all the other pins...

Are you reverse engineering someone else's product? If so, then design your own.

Chris

Listen to chris288... if you have a multi-layer board, surrender now! That said, it is a fairly straight-forward process on a single or dual layer board (top/bottom), I have done it. First, it will be a far more difficult task to identify the components on the board than to simply trace the traces...run the routing?...route the traces?...OH well, you know what I mean!

1 - De-populate the board if possible, this make the next step easier.

2 - Make photocopies of the board, both sides if needed, make a lot of copies.

3 - put the board in a safe place as you will be working on the photocopies from here on.

4 - It helped me to identify all of the cross-over/links and the relative locations of the components first.

Think of this process as like untangling string, your strategy will change as you go and as you go, you will learn and become more and more intimate with the circuit, often in ways you would have never expected. As you draw out your circuit on paper, you will frequently redraw what you have so far, on a new sheet often changing the locations of the components to make your circuit easier to draw. Make use of colored pencils and make notation on the photocopies of traces/sections you have already drawn on your circuit. Use the same colors on your drawing to correspond with the notations on the photocopy. Break the problem into smaller pieces...just like eating an elephant!

This is the process I use and it works. Del the Cat recommends patience, and I agree wholeheartedly! Good Luck!

If single-sided PCB, or only a few traces on the top side of a double-sided PCB, try these:

Try to identify each component before you start. This may take a little guessing if the manufacturer has ground off IDs.

Have a good quality plastic rubber (eraser if you're from stateside) handy. To clean it, rub it against your trousers (say against the side of the thigh). Do this regularly, if you use it a lot.

Also a pencil (2B or darker). And a piece of sandpaper to sharpen your pencil on.

After this exercise, you will know exactly what to do, providing you ever want to try again.

1. Get some tracing paper, like the stuff draughtsmen used before computers.

Trace out all the copper areas on to the tracing paper.

Turn the tracing paper over, and lay it on a sheet of white paper. Look at the PCB and sketch in the components on the tracing paper (in circuit diagram form) using a pencil. Alternatively, photocopy the mud map of the copper areas on to white paper (make sure you copy the mud map the right way up), then mark up components.

Now you can sketch the circuit diagram. You will revise it several times before you are happy with it.

2. Some people can draw a mud map straight on to a piece of white paper just by flipping then PCB back and forth and estimating by eye where components are placed with regard to the copper areas.

3. Lay the PCB on a sheet of glass (preferably pearl finish, not clear). Illuminate the underside of the glass with a strong light (fluoro preferred). Now with a pencil, start sketching the copper areas and components on to a piece of white paper.

Hi AA

1) There is no more Czechoslovakia. Just Czech and Slovakia. If you saw "Chechoslovakia" printed on the box (as the location of production) this means that this p.s. is old -probably from the 80's- and its pcb design is a simple 2 layer and not a multilayer. Then you could have more luck in your "copy-paste" procedure.

2) Making a test bench controlled by a microcontroller (as Chris suggested), although it is a clever solution, it will consume time and money. It's better to design a p.s. on your own than doing this.

3) It is better to identify the main components of the circuit before starting to draw the circuit. As an example, if it is a PWM p.s. (which probably is) there must be a PWM controller. See what chip is used and see its datasheet. You'll find the functionality of its pins and, probably, you'll find one or more applications. All these (and some personal knowledge on p.s. topologies) will help you to copy the circuit in an easier way, as your schematic should represent a known configuration (buck, boost, flyback e.t.c.).

You should be careful if this circuit is intended for commercial use, as the exact copy of a product is illegal. If I was you, I'd prefer to design a p.s. on my own.

I've done this a couple times with obsolete equipment that had to be kept in service for one reason or another. As several posters have indicated, a single-layer board is not that difficult. It does, however, require a bit of dedication and focus. I start at any input or output and follow the surface traces, drawing each trace and component as I get to it. As a trace or component of the board was committed to the drawing, I used a fine-point permanent marker to draw a line along the board trace showing the sections I had already documented.

A double-layer board is more difficult, but not impossible. Buy or build a small light box with a powerful light source. When you lay the board on the box, you will see shadows of the internal tracings. Careful concentration is required to differentiate the internal tracings from the surface tracks.

Anything more than 2 layers and it's impossible to differentiate between the traces in each layer, so I wouldn't even try.