How to build up confidence during your project?

Haloe

Member
2019-08-27 11:02 am
Recently, I have been designing a project. Actually, it is my first project. The thing is, after my design, i ordered PCBs. But when i get my PCB back, i found I forgot an important feature. So i have to add this feature and reorder new PCBs... Something similar happened several times, which really hit my confidence... And actually it cost much...
It is a bit depressed that i made so many mistakes. Could you pls give me some advice.
 

Mooly

Administrator
Paid Member
2007-09-15 8:14 am
My advice would be to write down your projects requirements and design to that... your own specification.

When designing boards keep going back and check, check check and check again. Not just basic layout but connections and component sizes as well.

Finally, and when you have a design on paper (or screen) that is correct and that works as you want then never go back and change anything in that design without a full and proper test of the proposed change.

It is easy to look at the circuit later and think that it would have been a good idea to add another cap here or a R/C filter network there and so on.

Don't do it without full testing of a prototype first or it will come back and bite with the changes causing some other unwanted behaviour.
 
Breadboard every part of the circuit if at all possible, with the actual devices.
Note the actual circuit as breadboarded and don't vary that in the PCB circuit without
going round the loop again.

Check the PCB schematic twice. Check twice, build once.


Never submit a PCB for production just after finishing it. Always check again in the cold light of the next day, thinking about such things as:
"are there mounting holes",
"have I checked the package dimensions and pinouts for _every_ part?",
"Did I forget connector(s) for power to the board?",
"Can I add some useful test points for commisioning?" - actually I just use vias, ensuring there is at least one unobstructed via on any interesting traces I can poke a 'scope probe onto

And make sure there are no design rule breaches....
 

nenad88

Member
2016-11-06 11:28 am
As for soic there ary many adapters you can use, there are many that need soldering or something like this.
HTB1NFfJSXXXXXXuapXXq6xXFXXXZ.jpg

You can get soic 16 version adapter and use 6,8,10,12,14,16 pin version chips with it.

Here is even sop28 https://encrypted-tbn0.gstatic.com/images?q=tbn%3AANd9GcRlmBhATuKutIkovrac8kE7D9Geo817Hu2iGVWQDNioxFO1sOPb
 
Last edited:
Recently, I have been designing a project. Actually, it is my first project. The thing is, after my design, i ordered PCBs. But when i get my PCB back, i found I forgot an important feature. So i have to add this feature and reorder new PCBs... Something similar happened several times, which really hit my confidence... And actually it cost much...
It is a bit depressed that i made so many mistakes. Could you pls give me some advice.

One thing that is important that you use a layout program that is fed by your schematic capture. Most CAD suites have that: you can be sure that the PCB is exactly the same connectivity as the schematic. Only one think to double check: the schematic.
Most of these apps not only take the PCB connectivity from the schematic but also show live connections on the layout and give warnings if you make a wrong connection.

It is almost impossible to manually transfer a schematic to layout except for very small and simple circuits.

Jan

Jan
 
Recently, I have been designing a project. Actually, it is my first project. The thing is, after my design, i ordered PCBs. But when i get my PCB back, i found I forgot an important feature. So i have to add this feature and reorder new PCBs... Something similar happened several times, which really hit my confidence... And actually it cost much...
It is a bit depressed that i made so many mistakes. Could you pls give me some advice.

Rushing a project is probably my biggest mistake.
I now take time to make sure it is correct before sending it off to get pcb's made.
Go over every part of the circuit to make sure it is right.
I have good PCBCAD software which has a lot of error checking.
 

Katheru

Member
2019-08-29 10:56 am
China
Just go rid of thinking that a project is quick and don’t take time. The waiting for a project is deserved. Found mistakes, solve it, and found again, solve again... It is helpful for yourself. If you mind the cost, I would like to say ALLPCB low-priced prototyping is almost negligible. Also cheaper shipping ways.
 
Just go rid of thinking that a project is quick and don’t take time. The waiting for a project is deserved. Found mistakes, solve it, and found again, solve again... It is helpful for yourself. If you mind the cost, I would like to say ALLPCB low-priced prototyping is almost negligible. Also cheaper shipping ways.

I rushed through error checking a pcb.
When it came back it didn't work.
I found two tracks shorted and running over each other.
I blamed the PCBCAD package for not picking it up.
So went back to the PCBCAD package and did error checking again and it found the error ! So, I either didnt run that clearance check or misread the answer to the check. More haste, less speed.