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power issue building custom mcu board

voxe
Associate

hi i have several questions about setting up STM32 chips as im trying to build a project which requires me to do so but ive encountered issues on my first step. im currently trying to set up my own MCU board using a STM32F722ZET6 144 however once i connect the st link it looses connection from the computer. i have used a pinout board which i then soldered wires to so it can be connected to a breadboard, the idea was not to create anything long term but to attempt to get it working. there are no issues with the reset, clock ect. parts of the circuit as it still occurs with them disconnected. for power im using a 3.3v regulator with 5v input which does create the correct power requirements with everything connected to what i believe to be correct, ive only setup the Vss and Vdd pins and not the power pins for ADC and USB. there are no shorts on the wires coming out, there appears to be none on the chip itself and i had help soldering by an engineer at work. i was planning to order some boards with the same setup and hope it works however when i went to do so in kicad, i was surprised that the chip was part of the library but it had diffrent pinouts with respect to the power supply compared to the datasheet. ive worked ith ics before but this is my first time trying something with an MCU and with the lack of working combined with kicad its thrown me into a loop. 

So im willing to accept there is a short i am unable to find but is this settup according to the datasheet correct?    id like to order the boards soon regardless of if this pinout does not work however i need to know if what ive done is correct.

secondly i wanted to ask what is the minimal setup required for an STM32 MCU. ive got the reset, oscillator, vcap, PWR_ON and BOOT setup according to the datasheet but is there anything else which would be required?

 

Could anyone provide any sources for information on setting up thease chips and building custom MCU boards, i was fairly confident that i could do it as ive build projects around various ICs and it could verry well jsut be a short but more information is always helpful. and thankyou for any help you can provide.

 

 

Screenshot 2024-02-11 002150.pngScreenshot 2024-01-29 115706.pngIMG_20240211_081654.jpg

1 ACCEPTED SOLUTION

Accepted Solutions
TDK
Guru

> Could anyone provide any sources for information on setting up thease chips and building custom MCU boards

The hardware design guide for the F7 series is here:

https://www.st.com/resource/en/application_note/an4661-getting-started-with-stm32f7-series-mcu-hardware-development-stmicroelectronics.pdf

 

In particular, note the part where VDDA/VSSA are required to be connected to VDD/VSS.

 

It's going to be hard to meet the recommendations on a breakout board, particularly for decoupling caps and VCAPs.

Nucleo boards are quite cheap, reliable, and quick to set up for development/debugging.

If you feel a post has answered your question, please click "Accept as Solution".

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3 REPLIES 3

A schematic of what you actually wired would help. Or the Kicad symbol you believe is wrong.

You need to wire the Analogue supplies and references as these are used by the PLL and POR, and not just ADC/DAC

I'd probably wire up USB power too. It's really there for systems running at lower voltages so you can power to USB high enough to meet specs.

Perhaps look at NUCLEO schematics, or some of the minimum boards you see on AliExpress etc.

Tips, buy me a coffee, or three.. PayPal Venmo Up vote any posts that you find helpful, it shows what's working..

thankyou I'm still unsure of the ki cad but the nucleo schematics do align with what's in the datasheet. I've tried wiring power to the analogue and USB supplies but the st link still disconnects so it looks like an issue with the board.  

TDK
Guru

> Could anyone provide any sources for information on setting up thease chips and building custom MCU boards

The hardware design guide for the F7 series is here:

https://www.st.com/resource/en/application_note/an4661-getting-started-with-stm32f7-series-mcu-hardware-development-stmicroelectronics.pdf

 

In particular, note the part where VDDA/VSSA are required to be connected to VDD/VSS.

 

It's going to be hard to meet the recommendations on a breakout board, particularly for decoupling caps and VCAPs.

Nucleo boards are quite cheap, reliable, and quick to set up for development/debugging.

If you feel a post has answered your question, please click "Accept as Solution".