LED flashing 3 times and not being able to program


I designed a board using the schematic available on the website to have a 12V power supply. I have attached the circuit used for this purpose.

I purchased the programmer chip pre-programmed, and I have checked the part number of the flash chip multiple times to ensure it ends with the letter "M".

However, after connecting the power supply, the board blinks three times and the programming process does not proceed.

Does anyone have any idea where my problem might be coming from?


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3 blinks means a problem with the flash memory. I spent a few minute tracing out the wires of your PCB layout. It looks correct. If the chip really is Winbond W25Q16JVUXIM (PCBA vendors actually using W25Q16JVUXIQ is a common problem), the only explanation I can imagine is a problem with the soldering. Everything I can see in your message really looks like this should work.
Thank you very much for your response.

Considering that I see the following image in the software, could the soldering issue be with the MIMX chip itself or the bootloader? I have soldered two boards and they are the same, and I have replaced the flash chip several times.


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