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DS90UB913A-CXEVM: DS90UB913A + DS90UB914A

Jeff YANG
Mastermind 9325 points

Part Number: DS90UB913A-CXEVM

Hi,

Currently testing the DS90UB913AEVM + DS90UB914AEVM. When testing the DS90UB913A + DS90UB914A alone, the Lock LED lights up. However, when connecting the BiTEK CVBS to ITU656 and hooking up the PCLK, the Lock LED turns off, and there is no video output. Measuring with an oscilloscope, the 27MHz signal looks like a sine wave.

Could it be that PCLK requires a clean square wave? The board settings and waveforms are as follows:

PCLK not connect to DS90UB913AEVM:

913.jpg

Thanks!

Jeff

PCLK connect to DS90UB913AEVM:

913-1.jpg

  • 0
    TI__Mastermind 28351 points

    Hi Jeff,

    Thanks for your message. Would you be able to provide the settings which were used to configure the UB913 / UB914 in this case? Regarding your setup using a "BiTEK CVBS to ITU656" could you provide a bit more background here? I'm not familiar with this particular chipset or test equipment.

    In this case PCLK would not be expected to be sinusoidal, a square wave is expected with high and low times as defined in the datasheet shown below.

    Best,

    Thomas

  • 0 in reply to Thomas Bejin
    Mastermind 9325 points

    Hi Thomas,

    The current setting is 12-bit low-frequency mode.

    'BiTEK CVBS to ITU656' uses 27MHz PCLK + 8-bit video data, with no HS/VS signals.

    The PCLK was not a sine wave; I later corrected the waveform. It is now a standard 3.3V square wave, but using jumper wires for connection causes significant over/under-shoot phenomena during measurement. thanks!

    Jeff

  • 0 in reply to Jeff YANG
    TI__Mastermind 28351 points

    Hi Jeff,

    Could you confirm if you're operating in external oscillator mode or with pclk from sensor? For the deserializer side on UB914, could you share the configuration script which has been run here and the mode pin configuration of the UB914A?

    Best,

    Thomas