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TPS23882B: Device setting get lost after reset, autonomous mode

Part Number: TPS23882B

Hi, Im using TPS23882B1 with two evaluation boards: 

TPS23882B1EVM-008 

BOOST-PSEMTHR8-097

Autonomous mode is selected via Jumper J5(2P-15W).

But PSE driver TPS23882B1 can detect other PD devices only if I do some manual settings in Enginering view.

After power reset all setting get back to default...Only autonomous mode stay, but all port are OFF, detection/CLS is also OFF.

How can I write these setting to TPS23882B1 to save it? 

  • Hi Martin,

    This device is meant to be standalone device and when pin 52 is selected the device should be able to operate. The device uses the default image that is built into the ROM. Therefore, any settings set by the host will not be saved. Everytime the device boots up, these settings that are set will need to be rewritten.

    The device should power on the port if the jumper J5 is set to 2P-15W. Can you confirm the this port turns on?

    Regards,

    Brandon

  • Hi Brandon,
    thank you for your reply. Jumper J5(2P-15W) is connected. I measured 124 kOhm between this resistor and GND.

    But If i read register status in TPS2388x(after power reset) , it seems unconnected or floating..

    registers:

    0x12 = 0x00

    0x14 = 0x00

    0x29 = 0x00

    How can I solve this? 

  • Upgrade from my side:
    I try do the same operation with another device (It is not avaluation board, but my own scheme, which are come from this ev. boards)

    Now: 

    0x12 = 0xFFFF - OK

    0x14 = 0x00 - still bad

    0x29 = 0x3333

    Detection still doesnt work after restart. If I toogle detection/cls manually..It says R low for connected/unconnected devices. Only PORT 3 is connected at the moment.

  • Hi Martin,

    What is the PD that is being used to connect to the PSE?

    Regards,

    Brandon

  • Hi Brandon,

    PD device is AS1138.

    Issue above (wrong R measurement) is caused by my wrong schematics. I missed put 22V zener diode between 15K resistor and LED diode of each channel ...So the PSE correctly measured this 15K value :-)

    But now, detection /clarification events still not run automatically after reset...

     

  • Hi Martin,

    Couple things here:

    1. From your screenshot, you are not loading SRAM. In order to ensure proper operation, loading SRAM is necessary. Please refer to this app note for how to load SRAM correctly. If using the GUI, please refer to User's Guide for loading SRAM. The latest SRAM version is v14 which can be found on the mysecure folder.

    2. Loading SRAM above may resolve about issue, however it appears you are operating in auto mode. From the screenshot, we can see that the port is turned on and doing detection and classification, is there additional issue?

    Regards,

    Brandon