• State
  • Locked Locked
  • Replies 6 replies
  • Subscribers 98 subscribers
  • Views 611 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

custom omap4460 board auto reboot!!!hardware problem

freme freme
Intellectual 300 points

Hi everyone ,please help me ,it is very seriously.
 we design the omap4460 board by ourself,Reference for the design of blaze,now we have 22 pieces board ,there are 18 pieces of them are work stable,but   4 piece of them are very unstable,when I use the GPU or IVA functions of the unstable board,the board we'll be reboot quickly,the more higer frequency of the GPU or IVA we set,the more quickly it reboot ,someone suggest me to test the supply voltage  provided for the unstable board ,then I test ,all of the supply voltage is ok, someone adviser me using the heat gun to  Add welding the unstable board,the I done,but not working ,

please help me ? My product can't wait so much time!!!!!

  • 0
    TI__Genius 10965 points

    Hi,

    Did you observe any odd log before the board reboots?

    Perhaps may be to due bad ram connection somewhere on the board. Can you provide me with schematic changes you have done to our design and perhaps high resolution photo of  both top/bottom layers of the board.

    Regards,

    Boyko

  • 0 in reply to Boyko Kazakov
    Intellectual 300 points

    hi thank you Boyko

     now I post the power supply schematic of our board.and two  high resolution photo of our board just as you say.now we have some new progress,when we set the CPU at 500MHz,GPU at 384M Hz,IVA at 430MHz ,the board can work stable ,we find that if we set the CPU is lower frequze,the board can work stable ,so we We feel that the higher frequency of the cpu we set ,the more power the cpu  need. then we have  two suspicious place,first,.we doubt the decoupling capacitance at the bottom of omap4460 is fake,when high speed circuit work,the power is supplied by it,if the capacitance has problem.the cpu work at high frequency is unstable,second,we doubt the pcb board  has some problem ,our board is 8 layer ,the inner layer connect by the buried via,if it is  manufacture not very well ,the  path of  electric current is  narrower ,it can't through enough power when the board work at high frequency? are we consider correct ?

    can you give me some advices

    the power supply of our board

    6761.power supply.pdf

     

  • 0 in reply to freme freme
    TI__Genius 10965 points

    Hi,

    Do you have smartreflex enabled on your board or the reset occurs even before those drivers are loaded.

    If you initialling the board with  lower clock speeds and  then you switch them up do you observe any strange fluctuations on your oscilogram near the decoupling capacitors.

    I still think it may be to loose solder joint of the omap soc itself.

    Regards,

    Boyko

  • 0 in reply to Boyko Kazakov
    Intellectual 300 points

    Hi Boyko,goodnight

    the  smartreflex is disable by our system.the phenomenon is that the system is reboot  suddenly and not has any log and sign .it just reboot when we set frequency is higher then 500MHz (eg.720MHz reboot after our program run two hours;1GHz it is reboot quickly.) when we solder a newer omap4460 soc on one of unstable board ,it is the same as before ,it is also reboot when the frequency is set more then 500MHz.

    best regards

    guoguodian

  • 0 in reply to Boyko Kazakov
    Intellectual 300 points

    Hi Boyko,I have some question,can you help me ?

     can you please send your phone number in my email? thank you ！ my email is guoguodian@126.com

  • 0 in reply to freme freme
    TI__Genius 10965 points

    You can open conversation with me on the top menu of the forum.

    Regards,

    Boyko