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.

DLPDLCR4710EVM-G2: DLPDLCR4710EVM-G2: picture disappears at power-on

Part Number: DLPDLCR4710EVM-G2
Other Parts Discussed in Thread: DLPC3439, DLPA3005

Hi

the output is missing after powering on the device. It flashes the picture once (< 1sec) and then it disapears (s. attachment)! 

The current consumption after moving the SW28 to the ON position is 150 mA. Arter pushing the SW21 switch it jumps to 230 mA!

The GUI is able to communicate to the device properly. Due to the problem mentioned above no picture is beamed on the output!

Please help us to get the device to run properly.

thanks

Device:

DLPDLCR4710EVM-G2 Board

SW Tool:

Light Crafter Display V7.4-4710EVM

  • Hi Lait, 

    Welcome to TI E2E Forums! Can you kindly confirm if you are using the latest FW available for DLPC3439 on TI.com?

    Thanks & Regards,

    Hirak.

  • Hi Hirak,

    The current version is:
    EVM Firmware: 1.6.0 (first figure)

    I downloaded the newest version (DLP4710-G2-FW: DLP LightCrafter 4710 Gen2 Firmware) 7.3.2 and uploaded it on the device. 

    There is no change yet. It still showing no image. It just flashes the image for short time (< 1 sec) and then the image disappears.

    previous version information:

    Currently:

    No change in the output:

  • Hi Lait,

    if communication is alive, can you check the LED current and LED enable status in GUI. Also can you try change the display patterns. 

    Also check the DMD flex cable is tight and intact.

    Thanks,

    Nvaneet

  • Hi Nvaneet,

    thank you for your answer.

    The LEDs are enabled with a current value of 10041 (mA). 

    The flex cables is tight enough and intact.

    There is no change when changing the display patterns. I tried all of them.

    I tried to change the LED currents down to the minimun (1423 mA). No change!

    The whole device consumes ~ 250 mA. I wonder whether the LEDs are enabled as shown on the GUI!

    What is next? 

    Lait

  • Hi User,

    Can you check the status in advanced mode of the GUI.

    Also can you probe the VBIAS, VRST and VOFS lines coming out of DLPA3005 PMIC. refer the schematic for signal (page 10) : 

    Probe the signal very carefully.

    Thanks,

    Navneet

  • Hi Navneet,

    Here is the status in advanced mode (s. attachment). 

    The voltage level of the VBIAS, VRST and VOFS is very low. I am measuring 11 mV to 0 V!

    I can't explain the low voltage over there. According to the schematic => VOFS = 10V, VBIAS = 18V, VRST = -14V...

    Thanks

  • Hi Lait,

    Looks like DLPA chip is not driving the DMD voltages, now we need to check if DLPA is throwing any fault.

    Can you install this GUI :

     After installing this GUI, check if you are able to communicate to EVM using this GUI.

    Then open advanced mode -> connection -> I2C -> connect

    Commands -> debug -> Write PAD register address 

    Now Read PAD register, put length 1 and click Get:

    Do the same above steps for Address 0x0C.

    Send me the read back data for both register address 0x01 and 0x0C.

    Thanks,

    Navneet

  • Hi Navneet,

    Thank you for the detailed reply. 

    After installing the GUI, I was able to communicate to the EVM. 

    The I2C connection was successfully established. I was not able to locate the "Write Pad Register Address" into the debug section. The only thing there is "Read Device Keyfusecheck".

    I couldn't find the "Write Pad Register Address" anywhere else. 

    Please let me know if something went wrong over here.

    Thanks,

    Lait

  • Hi Lait,

    I am sorry.. i checked and find out this option is currently not available in the GUI. 

    I have alternate option to check if DLPA is throwing any fault. Probe the INTZ signal coming out of DLPA.

    check the figure 28 in the datasheet of DLPA3005 for fault condition : http://www.ti.com/lit/ds/symlink/dlpa3005.pdf 

    If there is any fault occurs in DLPA then it will make INTZ low and respectively it will make all DMD voltages disable.

    Share the result of the INTZ signal status to move forward.

    Is this EVM behaves like it from the beginning or recently ? When did you purchase this EVM ?

    Thanks,

    Navneet

  • Hi Lait,

    Did you get chance to probe the INTZ status ?

    Please let us know if you resolved your issue or need further assistance.

    Thanks,

    Navneet

    If a post answers your question, please click the "Verify Answer" button.

  • Hi Navneet,

    Yes. I found the problem. The 4710EVM has a high peak current at start-up which drives my power supply device into lock mode. It is not able to afford the start-up current.

    I am using now two channels of a digital supply device and it is working fine. 

    The peak current on 0.1 Ohm resistor at start-up (SW28 to ON):

    And here is the current consumption after pushing switch SW21:

    Thank you very much for your support. 

    Best regards

    Lait