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TPS40400: TPS40400 program burning issue

Part Number: TPS40400

Hi Expert,

My customer is using TPS40400 on one project. During the program burning procedure on the product line, they found one module couldn't import the input UVLO register value successfully. They checked the operation method and found this was caused by the power on and power off sequence. After that, all of the module couldn't import the input UVLO value successfully even they correct the power sequence. Could you check if the below process is correct for burning the program during production?

1).Power Off--------2).put the module on the bench slot-------3). Power on-------4). import the program--------5). the screen shows the program imported successfully-------6). Power Off--------7). Pick out the module from the bench slot--------8). Put another module on the bench slot and repeat step 1 to step 7

  • We are reviewing your issue and will get back shortly

  •  

    The procedure that you describe appears to be correct, assuming that the program that is being imported includes the required "STORE" command to commit the changes to NVM and the Input UVLO command is part of the import sequence and you are waiting long enough between

    Are you using TI's FUSION software or another vendor's software to load the commands to the device?

    Are you importing from a manufacturer's programming script or a FUSION project file?

    Can you share the programming script or project file with me?

    Are you able to share screen shots showing the sequence?

    If you are using the FUSION Digital Designer, what import options are you using?

  • Hi Peter,

    Thanks supporting this question.

    1. The customer is using the Fusion Digital Designer

    2. I was not able to get the project file. The input UVLO value is the first command imported in programming. I would like to describe the customer's incorrect operation when they got issue.

    Power off the module----import the program---it shows wrong indication, see the below figure----power on the module and no restart the software---try import the program again, it shows the project imported successfully, while the UVLO register is not imported the correct value.---Do the steps which I mentioned in my first E-mail and don't restart the software. All the following modules can't import the UVLO value correctly.----Restart the software, it works!

    Could you tell why the UVLO register can't be configured successfully unless restart the software?

    1).Power Off--------2).put the module on the bench slot-------3). Power on-------4). import the program--------5). the screen shows the program imported successfully-------6). Power Off--------7). Pick out the module from the bench slot--------8). Put another module on the bench slot and repeat step 1 to step 7

     

     

  •  

    I am trying to make sure I understand the issue, is VIN_OFF the only command that is not being imported correctly, or is it stopping when the VIN_OFF command NACKs?

    A couple of possibilities:

    1) The connected device is not located on Address 36d, so it is NACKing attempts to write to 36d if the project file is loaded before a device is connected.  Rebooting the FUSION Digital Designer software runs an "On Line Auto Detect" routine that searching valid addresses to "discover" the connected devices, which corrects the Address.

    A screen shot showing a successful write after rebooting the FUSION Digital Designer software should show this as the address the device is connected to would change.

    2) The Module's default WRITE_PROTECT value before you start programming, and the FUSION GUI software not realizing that the Write Protect is causing the TPS40400 to NACK the write attempt to VIN_OFF when the FUSION GUI does not know to disable WRITE_PROTECT.

    A screen shot of the PMBus log after a successful write should also show this, as would a screen shot of the "Config All" tab of the Module before importing the project file would also show a non-zero WRITE_PROTECT value.

    The TPS40400 does have a relative data checker that prevents VIN_OFF from being programmed to a value greater than VIN_ON, but that should not be preventing the writing of a VIN_OFF value of 2.5V since the minimum VIN_ON value is 2.75V