• State Resolved
  • Locked Locked
  • Replies 8 replies
  • Answers 2 answers
  • Subscribers 64 subscribers
  • Views 135 views
  • Users 0 members are here
Support feedback
Options
Options
Similar topics

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.

UCD3138PSFBEVM-027: Problems with UCD3138PSFBEVM-027

koumei okahara
Prodigy 30 points
Part Number: UCD3138PSFBEVM-027
Other Parts Discussed in Thread: USB-TO-GPIO2, UCD3138FW-PSFB, UCD3138

Tool/software:

Hello

I am trying to evaluate the UCD3138PSFBEVM-027.

I connected the USB-TO-GPIO2 to the UCD3138CC64EVM-30 and was able to scan the device in ROM mode without any problems.

However, the firmware download did not complete successfully.

As a test, I shorted J2 on the UCD3138CC64EVM-30 and turned off the 400V power supply on the UCD3138PSFBEVM-027, and was able to download the firmware successfully.

Furthermore, when I turned on the 400V power supply to the UCD3138PSFBEVM-027 from this state, the circuit itself worked properly and 12V was output, but Fusion Digital power studio did not start properly.

When I connect UCD3138PSFBEVM-027 to UCD3138CC64EVM-30, it seems like data communication via PMBUS is not possible. Is there any problem?

Note) I have not modified any of the source code of UCD3138FW-PSFB.

  • 0
    TI__Expert 6200 points

    Hello Koumei,

    Are you setting your USB-TO-GPIO2 adapter to 400kHz or 100kHz communication? The USB-TO-GPIO2 may default to a 1MHz communication. The UCD3138 currently cannot support 1MHz communication. Typically if you can detect the UCD in ROM mode but when trying to download firmware you get the "Error: Firmware Download Error" message, then you are communicating at 1MHz. You must choose either 100kHz or 400kHz.

    In your last screenshot, it looks like 1MHz is selected. Try selecting the other Bus speeds.

    Regards,

    Jonathan Wong

  • 0 in reply to Jonathan Wong
    Prodigy 30 points

    Hello Jonathan

    Thank you for your reply.

    I tried changing it to 100kHz but it was exactly the same.

    I followed the steps in "8.Test procedure" in the user guide again to check the behavior of UCD3XXX_GUI and found that the firmware download was successful, but when I tried to run the firmware from the flash afterwards, there seemed to be no response from PMBUS.

    (See the figure below)

    As I mentioned last time, when I shorted J2 on the UCD3138CC64EVM-30 and supplied power from USB-TO-GPIO2, and the UCD3138PSFBEVM-027 was not powered, I could communicate with the UCD3138 via PMBUS normally, so I think that the level of the signal connected to the UCD3138PSFBEVM-027 is preventing the PMBUS from working. What do you think?.

    I don't know if this is related, but even when S1 is off, 12V is output. Is this the correct state? . I thought that it would not be output when S1 is off.

  • 0 in reply to koumei okahara
    TI__Expert 6200 points

    Hello Koumei,

    Sorry to hear you are still encountering problems. The UCD PSFB EVM User's Guide specifies to keep S1 off. 

    After downloading the firmware, can you try unplugging and replugging the PMBus adapter, and then searching for ROM mode or DEVICE ID again? If ROM mode is detected, then click "Execute program flash". 

    Try removing the J2 jumper and shorting the J6 jumper on the UCD control card. This way the 3.3V will come from the UCD PSFB EVM instead of the PMBus adapter. We have seen issues where supplying power on a control card via the PMBus adapter while controlling an application EVM causes error. This is likely due to mismatched groundings since your pmbus adapter is grounded to your laptop while your application EVM is grounded to your power supply and load.

    Regards,

    Jonathan Wong

  • 0 in reply to Jonathan Wong
    Prodigy 30 points

    Hi Jonathan

    I tried as you instructed, but it didn't solve the problem.

    I'm in exactly the same situation.

    As a test, I disconnected the UCD3138CC64EVM-30 from the UCD3138PSFBEVM-027, connected the 12V power supply (VAUXS) and GND as shown in the photo below, and tried to supply power only from the UCD3138PSFBEVM-027. I was able to successfully download the firmware and communicate via PMBUS.

    Based on this result, I think there may be some signal between the UCD3138PSFBEVM-027 and the UCD3138CC64EVM-30 that is affecting the PMBUS.

    What do you think?

  • 0 in reply to koumei okahara
    TI__Expert 6200 points

    Hello Koumei,

    First, thank you for sending pictures of your setup. This greatly helps my understanding and will help us solve your problem more quickly. Please continue sending high quality photos in the future.

    Just to confirm, since the photo is a little blurry, is J2 not populated? If you can send another higher quality photo, then that would help. 

    Disregarding the PMBus, you said that the circuit was correctly output 12V. Does this mean that if you probe the UCD3138 DPWM pins, you get the correct DPWM waveforms? Thus, the only problem is that you cannot communicate with the UCD3138 via PMBus while the UCD3138 is controlling the PSFB?

    Here are some more thoughts:

    1) Try switching the PMBus speed to 400kHz

    2) Previously, we discussed the PWR050's unreliability. Have you probed the PWR050 without the UCD control card attached to ensure you are getting the right outputs? Link to previous E2E

    3) Your GUI does not show the typical error message if the GUI cannot find the UCD at all. See my example screenshot below. I connected the USB-TO-GPIO2 without connecting the UCD3138 and launched Fusion Studio Online. The error message shows "DEVICE_ID scan (UCD3xxx)". Your message shows "Isolated1". I will try an investigate what that error message means. 

    Regards,

    Jonathan Wong

  • 0 in reply to Jonathan Wong
    Prodigy 30 points

    Hello Jonathan

    Thank you for your reply.

    Q1:Just to confirm, since the photo is a little blurry, is J2 not populated? If you can send another higher quality photo, then that would help. 

    A1:Yes. At this point, J2 is open. Therefore, the power for the UCD3138CCEVM-30 is supplied from the AUXS (12V) of the UCD3138PSFBEVM-027 via the regulator (U2: TPS715A33DRBR) mounted on the UCD3138CCEVM-30.

    Q2:Disregarding the PMBus, you said that the circuit was correctly output 12V. Does this mean that if you probe the UCD3138 DPWM pins, you get the correct DPWM waveforms? Thus, the only problem is that you cannot communicate with the UCD3138 via PMBus while the UCD3138 is controlling the PSFB?

    A2:Yes, that's correct.I have not yet seen the detailed waveforms of each part, but when the UCD3138CCEVM-30 is mounted on the UCD3138PSFBEVM-027, 12V is normally output to the output terminal block, and there is no problem even when a load of about 4Ω is connected.

    From this, it seems that the control part is working normally, but only the communication with PMBUS is not working properly.

    I will check the following two points later.

    ①Try changing the PMBUS speed to 400KHz

    ②PWR050 output

  • 0 in reply to koumei okahara
    TI__Expert 6200 points

    Hello Koumei,

    Glad to hear that the control part is working and that the only problem is the PMBus communication. Do you have an old USB-TO-GPIO (2006) adapter like this one: https://mou.sr/3HmBHIT.

    I have been doing testing on my own and I was occasionally running into the same problem where the firmware is successfully downloaded using the UCD3xxx Device GUI but I cannot open the Fusion Studio Online. If I did run into the problem, then random fidgeting with the USB-TO-GPIO2 adapter (unplugging and plugging back in on both the USB-A side and mini-B side) seemed to fix the problem. However, I did not have this problem at all with the USB-TO-GPIO (2006) adapter.

    I think this is because the USB-TO-GPIO (2006) adapter is not capable of 1MHz PMBus speed. I suspect something may be wrong where the USB-TO-GPIO2 adapter is defaulting into a 1MHz PMBus speed and not retrying in 400kHz or 100kHz on the Fusion Studio Online.

    Regards,

    Jonathan Wong

  • 0 in reply to Jonathan Wong
    Prodigy 30 points

    Hello Jonathan

    Thank you for your reply.
    The control part is working and the output is normal, so I will continue with the evaluation.