Small PCB board doesn't work when it's cold

[brunofunchas]

Hi,

I have a small PCB board with just two IC's, zener, diodes, resistors and capacitors.

That problem is that the board does not work when it is cold and after it warms up, it works fine.

Is it possible that the problem are the IC's? Or do you think it is probably from another thing?

Thanks,
Bruno

 

[keith1200rs]

Small PCB board

You will have to show a circuit diagram at least!

Keith

 

[brunofunchas]

Re: Small PCB board

Hello,

I do not have the circuit diagram. I will take a picture of the board.

Regards,
Bruno

 

[keith1200rs]

Small PCB board

Bruno,

A hand drawn circuit would be fine or a link to where you got the circuit from. A picture of the board is not much use.

Keith.

 

[pranam77]

Re: Small PCB board

Hi, I have a small PCB board with just two IC's, zener, diodes, resistors and capacitors. That problem is that the board does not work when it is cold and after it warms up, it works fine. Is it possible that the problem are the IC's? Or do you think it is probably from another thing? Thanks, Bruno

As per your post, i guess you cant debug the fault. As you have mentioned, if the Small PCB is having just two IC's, zener, diodes, resistors and capacitors, just remove all components and replace with new ones. Your problem will be solved instantly. Cheers

 

[karesz]

Small PCB board

Hi,
...and if the components are removed; is more light possible to take a circuit (for future events) from board ...
K.

 

[brunofunchas]

Re: Small PCB board

Hi,

Since it is a small board, I can in fact substitute all the components.

But I would like to know your opinion If I had instead a very large board, what are the components that have a higher probability to malfunction as I described in my first post?

The IC’s can malfunction when cold and function correctly when warm? The resistors? The zeners?

Thanks in advance.

Regards,
Bruno

 

[keith1200rs]

Small PCB board

Bruno,

You need to establish what the problem is first. It could be that you have a floating input that drifts to a point where it works due to a bad design or connection. If it genuinely a temperature related problem I would track it down with a freezer spray.

Keith.

 

[karesz]

Small PCB board

Hi,
In my opinion is to sort in temperature for malfunction is falsh!
Temp`s are question of dimensioning the circuits too, so can be a "worm component" absolutly normal in function... Nobody can it so generell say for you.
K.

 

[powersys]

Small PCB board

You've never described the function of your circuit. Has its function anything to do with temperature?

 

[brunofunchas]

Re: Small PCB board

Hi,

The board is used on an industrial machine and it's function is to rotate a set of pins when the newspaper arrives. It is a stacker for newspaper that comes out of the printing press.

The problem was solved by changing the IC's and a zener.

Thanks for the inputs.

Regards,
Bruno