STM32F4 - Discovery fail

[regiuliano2009]

Posted on February 17, 2012 at 11:44

Dear

STe2e Community,

I'm newbie to STM32F4 programming so I'm starting using a Discovery Board. I'm searching to get working a led on/off circuit with power terminal of the board but I don't know I burned 2 discovery board. I mean that the ST-LINK is not responding and LD8 is red. In the other board also LD5 is red. Is there any procedure to make these boards start working again or I wasted my money? Thx to everyone for the replays. CX3 #me-too

[regiuliano2009]

Posted on February 20, 2012 at 12:40

thanks STone e Donald,

by the Donald's experience I started to investigate the problem by an electrical level. When the board is USB powered I have in Vin_U1 a voltage of 2,4V and in Vout_U1 2,4V and the regulator isn't working. I looked at D1 and it has a voltage drop of 2,4V on him (!!! I think it's abnormal... do you think?). So I power on the circuit by an external power supply, (As I said before the F4 was still working) and I started to look at the voltages around the circuit. U1 is working good 5->3,3, D3 3,3->3 ad D1 is off. Good. So, I attached my USB cable CN1 and ST-Link started working again!!!!!!!!!!!!!!!! O_o So, I'm asking you which is the problem with my boards. Is D1 the problem? Like Donald, I think that I have touched 5V with 3V external pin in my first board. thank you again

[regiuliano2009]

Posted on April 13, 2012 at 16:21

I'd like to send some fresh news about the question.

The problem was caused by D1 diode burnig up. I have changed that and the board started working again. So D1 work as protection diode well. Whatever, D1 is very sensible to rapid usb tension/current variation, so keep attention when removing usb cable from discovery!! 🙂 Then I have made an experiment trying to power the board from 5V pin with 8-9 V. Then the voltage regulators U1 e U3 failed down (as on datasheet). So I changed them and the discovery started working good (D1 was untouched). Hope will be useful. C

[khaled3310]

Posted on October 16, 2012 at 19:03

Hi 

I bought a new STM32F4 this days and it gone burned or something like that i have a warning in IAR that the st link is not connected and a regulator in the debbouging part of the board becomes very hot and becomes burning after few seconds when the board is under supply i think that i have your same problems so how can i proceed to repair it and do not

Remarque the last program that I download is still running perfectly

Thx for help

[emalund]

Posted on October 16, 2012 at 21:59

The problem was caused by D1 diode burnig up. I have changed that and the board started working again. So D1 work as protection diode well. Whatever, D1 is very sensible to rapid usb tension/current variation, so keep attention when removing usb cable from discovery!! 🙂

I do not have a discovery board, so this may be irrelevant for this. ANYTHING USB that does not use standard USB connectors should ALWAYS be connected last and disconnected first at the end with a standard connector. The reason being that the standard USB connectors are made so that ground always connect first and, as a result, a lot of USB stuff WILL blow if something is connected before ground. Been there, seen that Erik

[arro239]

Posted on November 03, 2012 at 12:31

here is my experience:

I have mistakenly ground the +5v pin and the board went off. First I've powered it via the VDD pins (external power) and the chip worked, so it was only the st link section  which was off. I have tried the DFU path with using the second USB connector to flash the chip this way but it did not work - USB device not recognized etc. Now the actual fix: took a small wire and bypassed D1 diode, and  this got ST link back  working again!

[daviddawe1982]

Posted on April 29, 2013 at 09:45

well i killed my discovery as well it will only power with jp1 disconnected and the mcu gets hot as well

[shafqathussnain]

Posted on May 10, 2014 at 15:51 I have also the same problem please tell me its solution if you have found.

[Tesla DeLorean]

Posted on May 10, 2014 at 18:05

I have also the same problem please tell me its solution if you have found.

Sorry to hear that, but what exactly is YOUR problem, and what tests and suggestions from the thread have you tried? If you've damaged components on the board your option is to locate and replace the damaged components, or replace the board.

[shafqathussnain]

Posted on May 11, 2014 at 05:05

I am using STM32F4 Discovery I am having problem with it when ever I connect it with USB through PC it does not show SWD and JTAG and its LD1 remains green and its IC for debugging becomes very hot. Even if I connect it with external supply this IC STM32F103C8T6 becomes very hot.

Before this it was working properly. Last time when it started this behavior I was debugging my code. It is taking 750 mA current. I was using it to drive two motors through L298 IC without opto-couplers.

[shafqathussnain]

Posted on July 15, 2014 at 09:59

I am using STM32F4 Discovery I am having problem with it when ever I connect it with USB through PC it does not show SWD and JTAG and its LD1 remains green and its IC for debugging becomes very hot. Even if I connect it with external supply this IC STM32F103C8T6 becomes very hot.

Before this it was working properly. Last time when it started this behavior I was debugging my code. It is taking 750 mA current. I was using it to drive two motors through L298 IC without opto-couplers. Kindly provide me solution of this problem.