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DS90UB914/DS90UB913 Hot-Swap

Hello,

Are there concerns with hot-swapping the DS90UB914/913 SERDES link?  We are considering a removable connector with power, ground, D-, and D+ from the SERDES link.  Are there any application notes for this?

Thanks for your help.

  • Hello Nick,


    Can you please explain a little more as to the application and what you mean by a "hot swap"? In terms of power-up sequencing, a hot swap can be performed as long as you follow the guidelines in our datasheet. One guideline that is also being included in our new datasheet revision is for the requirement of the 914A device to be PDB reset (either manually on the board or through I2C commands) after the 913A. Therefore, if you perform a swap, the 914A must be PDB reset regardless after initial power-up of this device.If this is followed, hot swapping the devices (assuming here unplugging/replugging the devices together) should work fine.

    -Sean

  • Hi Sean,

    The application is a camera system with removable camera "heads" with a 913 Serializer that are powered by a base with a 914 Deserializer. By hot swap, I am referring to having a camera unit powered on, then having the user remove the camera head, and replace it with another camera head without powering the unit down. In doing so, because of the connector we are using, the D+, D-, power, and ground pins supplying the 913 (serializer on the camera head) may be disconnected and reconnected in any order (due to slight differences in pin length, angle of insertion, etc). So, there is a chance D+ and D- are connected before power, etc, along with possibly some ESD/over-voltage concerns associated with connecting/disconnecting pins with the 913/914 powered up.
  • Nick
    You can hotswap, but it is best to reset the deserializer after the swap to allow it to re-calibrate itself for the cable length and driver etc. This can be done either through a register written reset, or via hardware with the 'PDB' pin.