main chip too high

[chenjun]

hi, i currently used nxp1176 main chip as a board.Now I encounter some problems, and I don't know where to check the problems. The current corresponding to the empty burning program is 0.03A. There is a little difference between the CPU temperature calculated according to the calculation formula in the data manual and the actual size (difference of 2 degrees), and then the overall circuit current of the burning screen display program is 0.12A (without LCD) (the current entering the CPU should be calculated). According to the calculation formula, it is 41 degrees, but the actual CPU is 56.3 degrees (the difference is very obvious).

thanks.

[PabloAvalos]

Hi @chenjun 

Thanks a lot for reaching our technical support. I really appreciate your patience.

Regarding your concern, may you tell me what are you trying to do? Then, just to be on the same page, what do you mean with "the overall circuit current of the burning screen display program" ? Hopefully you may clarify those things, because I am not understanding your question. Something that can help, it might be a screenshot from the datasheet page you are watching the formula, and which is your goal with that one.

I will stay tuned to your answer. Please let me know if you have more questions.

Best Regards.

Pablo Avalos.

[chenjun]

hi,Pablo Avalos.

The temperature difference between the main control calculated according to the data manual and the actual measured temperature is very large (the main control temperature calculated according to the manual is 43, but the actual temperature is 65 (captured from the thermal imager)), but all peripherals of the board can be used normally. I want to ask whether this phenomenon is normal and how to solve it if it is abnormal.

Best Regards.

Chen Jun

[PabloAvalos]

Hi @chenjun 

Thanks a lot for your reply and many thanks for your patience.

Regarding your question, it might be for several reasons, probably the environment of the mcu, mcu damaged or overcurrent on some part of the board where the mcu is mounted. In this case, I would like to know which is the formula and the page from the reference manual that you are using to calculate that temperature and what are the parameters that you are considering for that one?

Hope you may help me with that information, so I can help you with. Please let me know if you have more questions or any comments.

Sincerely,
Pablo Avalos.

[chenjun]

Hi,@Pablo Avalos

Thanks a lot for your reply.

In response to your question, the chips we use are purchased through official channels, and there should be no problem; The formula for calculating the temperature is calculated according to the formula in the third small point in 4.1.2 in the reference manual; Then, if the circuit of the surrounding circuit is too large, it should be very hot t

hrough the thermal imaging analyzer. However, the thermal imaging analyzer shows that only the center of the CPU is the most heated.

Sincerely,

Chen Jun

[PabloAvalos]

Hi @chenjun 

Please accept my apologies for the late response. We had some backlog on the requests these days. I truly appreciate you were so patient.

Regarding I am watching at your images, and after double-checking with my teammates, this is the expected behavior, because the core in the mcu is the one that is going to be warming up, and not the modules attached to it, that's why you are seeing that heat point on your thermal camera. Then, if the temperature calculated it is not the expected, you should check the surround elements on the circuit and the clock frequency that your core is running on your application, to determine the correct temperature.

Hope the information was helpful, please let me know if you have more questions.

Best Regards.
Pablo Avalos.