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.
Tool/software:
Hi folks,
I've designed a custom Wi-Fi board using the CC3235S chip. Upon powering up, the board operates correctly and I can see the expected 1.2V and 1.9V on the DCDC_DIG and DCDC_ANA outputs..
However, I'm encountering an issue with the reset pin. The board's behavior seems to depend on the duration of the reset period. If the reset duration is very short, the chip boots up properly and the voltages on the DCDC pins are as expected. But if the reset duration is longer (e.g., 1 or 2 seconds), the chip fails to boot up after the reset is released.
Has anyone experienced a similar issue or have any insights?
Thanks,
Saber
Hey Saber,
I have assigned this thread to one of out HW experts to support. Please allow them until tomorrow to respond.
Hey Saber,
Can you please give me more details regarding your custom board? a schematic is preferable.
Also, can you please elaborate on all the actions that you're trying to perform? what are you doing prior and after asserting the reset? In what environment? etc.
Moreover, when using the nRESET pin, few things need to be taken into account:
- The nRESET pin of the CC3235x device must be held low until the VBAT supply to the device is
driven and stable.
- For 1st time power-up the nRESET timing after VBAT and VIO supply are stable must be 1 msec.
Please see 1st time power-up timing tables described in chapter 8 within the datasheet.
I also recommend looking into the device's user's guide for further information.
Both datasheet and the device's users guide can be found in the product page within our website: https://www.ti.com/lit/ug/swru543a/swru543a.pdf?ts=1720528071957&ref_url=https%253A%252F%252Fwww.ti.com%252Fproduct%252FCC3235S
Regards,
Omri
Hi Omri,
Thanks for the reply. I have replicated the schematic (tied pins 10, 54, 37,39, 44) from the Launchpad cc3235s board (the schematic is attached bellow). I am using Uniflash to connect to the chip via Serial port. For this I am using the Launchpad onboard headers as shown in the picture below:
When connecting the RX,TX, Reset and GND to the onboard CC3235S, I am able to connect to it. But when connect them to the custom boar, it keep throwing 'Timuout' error.
I have tried all possible SOP configurations, including 010. To ensure that the Reset is not released before the VBAT, I also manually holds the reset button, power up the board, and then release it, but still no luck in connecting to the device.
I believe there is something wrong with the reset mechanism, but not quite sure what,
Hi Saber,
You've mentioned that you used a custom board. Can you please provide its schematics?
Btw, The PDF link that you've attached isn't working, can you attach the PDF to this thread?
Regards,
Omri
Ops. sorry, I didn't notice the link is not working. Please see blow
5430.Wifi.pdf
Hi Saber,
Four layers are OK.
From the past I remember some issue with reset pin and CC32xx devices reported here at E2E forum. But I am not sure if this was somehow related to your case. Unfortunately I am not able find that thread now.
Jan
Hi Saber,
Can you please specify what are the exact values of R5 and C13?
Just want to make sure they're correct.
Thanks.
Yes These are indeed the correct values, just wanted to make sure.
Let me check this case further and I'll get back to you as soon as possible.
I am writing this just in case someone else has faced the same issue.
It turned out we have mistakenly assembled a 48Mhz Crystal instead of a 40MHz, Replacing the crystal with a 40MHz one has solved the problem and we are now able to flash the board.
Thanks everyone
Glad to hear that you've figured out this issue and sorry I couldn't be much of an help.
Feel free to approach me if any further issues are arising in the future.
Best regards,
Omri