Hi all,

I am stuck with a problem with the ADC14.

When the PSOC gets warm, the reading of the ADC14 suddenly drops down a significant number and stays down until the chip has cooled down again. I have a simple PT1000 with a resistor attached to the input, nothing should happen there. The voltage should be stable at 5.00V.

I could prove this several times by heating the PSOC with hot air and cooling it down again.

I am talking about a start temperature of 20 degrees centigrade (normal room temperature) and a top temperature of 50 degrees centigrade (not too hot). The jump happens at around 40 degrees centigrade.

Until now I can not exclude that there is another design problem on my board, but I think this may be a problem with the ADC or its settings.

Could you please let me know what problem I might have run into?

Best regards,

Turtle

Hi, have you solved this problem yet?

Terrence!

COuld You please explain what You mean?

regards

@robertseczkowski,

The post is a week old, perhaps he has already found a solution.

The problem is still there.

But in the mean time I found out that the affected board takes significantly more current than another board that does not show this effect although it should be identical.

Still investigating. I will post when I found the solution.

long time ago...,

but the problem is still there.

On the board I wrote about last year, there was one IC misplaced that lead to the higher current.

But even after fixing that, the measurement was still temperature dependent.

In the mean time, I have tested about 30 boards, 3 of them show the phenomenon that the reading drops when the board reaches about 40 degrees centigrade.

I have also tested "normal" boards. They show a drop of the readings when the board temperature goes up to more than approx 75 degrees centigrade, which I think is acceptable.