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HD3SS3220: Power Sequencing

Shmuel Davis
Expert 2930 points

Part Number: HD3SS3220

Is there any special power sequencing between VBUS_DET, VDD5 & VCC33 ?

I would like to power VDD5 via the VBUS protected by a TPD1S514-1 (ramp time = 23.mS) which in turn will supply a +5 to +3.3 regulator (EP53F8QI:soft start=1.62mS max) ! 

  • 0
    TI__Genius 16150 points
    Hello Shmuel,

    There is not a specific power-up/down sequence for the H3DSS3220. Even this device supports dead battery, thus, the sequence is not critical.

    Best Regards,
    Luis Omar Moran
    High Speed Interface
    SWAT Team
  • 0 in reply to Luis Omar Moran
    Expert 2930 points
    Dear Luis Omar Moran,

    My VDD5 of the HD3SS3220 is being powered by the VBUS_SYS of by a TPD1S514-1 . If there is an over voltage fault the VDD5 of the HD3SS3220 will see a MAX 5.99V for ~100ns before the discharge circuit reduces the voltage below 5V. Can I assume that this enough protection ?
  • 0 in reply to Shmuel Davis
    TI__Genius 16150 points
    Hi Shmuel,

    It could be enough protection theoretically, but TI does not recommend this condition. Be aware absolute maximum ratings are only for extreme and random conditions (not frequently). This scenario could be decrease the long life of the device.

    Best Regards,
    Luis Omar Moran
    High Speed Interface
    SWAT Team