STM32F405RGT6 Custom Board LED not working anymore

[huhuhaha]

I'm currently working on my custom STM32F405RGT6. I've soldered the minimum systems (STM32F405RGT6 + Necesary Resistor n Capacitor + LED ). I've been able to program the MCU to blink the LED at first. So i start to adding other components

I've been adding the MIC5504-3.3v LDO by alternatively change the components using AP2112-3.3V LDO. I've compared both datasheets and it should be working properly. Also, i've been soldered the LM7805 Ic too. After soldered that two ic's, i reprogram the STM32. The result is my led now can't working (blinking) anymore, but the STM32F405RGT6 seems had no problem (because it still managed to be debuged and programmed). What makes this happen ?

[mƎALLEm]

Hello @huhuhaha and welcome to the community,

You can program the MCU but you cannot toggle the LED? if you succeeded to program the MCU, from my stand point,  this is no more a regulator issue.

[huhuhaha]

I also think of that. but i still finding the problem of my blinking led

[Tesla DeLorean]

Each of the VCAP capacitors should be 2.2uF

[mƎALLEm]

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@Tesla DeLorean wrote:

Each of the VCAP capacitors should be 2.2uF

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Indeed and with low ESR. From AN4488:

 

[huhuhaha]

Thanks for the reference, i will try it

[Andrew Neil]

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@huhuhaha wrote:

the STM32F405RGT6 seems had no problem (because it still managed to be debuged and programmed). 

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What, exactly, do you mean by "debugged" here?

Have you stepped through the LED-blinking code? Does it successfully go through the code to set the pin high & low?

What do you see if you probe the pin externally?

 

If you set the PC13 output low, and then externally short the LED cathode to GND - does it light?

PC13,14,15 and PI8 are subject to limitations:

https://www.st.com/resource/en/datasheet/stm32f405rg.pdf#page=205

 

You should be OK with sinking the current for your LED D1:

https://community.st.com/t5/stm32-mcus-products/stm32f030-pc13-14-15-current-sink-limits/m-p/717014

But what does REF_DIR do on PC14 ?