• State TI Thinks Resolved
  • Locked Locked
  • Replies 1 reply
  • Answers 1 answer
  • Subscribers 33 subscribers
  • Views 548 views
  • Users 0 members are here
Support feedback
Options
Options
Related

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.

DS90CF386: about DS90CF386 reference circuit

Vera Mao
Expert 5065 points

Part Number: DS90CF386

hi dear supporting team,

for the reference design of CF386, Should customer isolate PLL_GND , LVDS_GND AND VCC_GND through 0 Ohm or ferrite bead?  and for RXOUT serial resistor, should they use 50 ohm? tks!

  • 0
    TI__Mastermind 35130 points

    Hi Vera,

    It looks like you're using the EVM as reference (http://www.ti.com/lit/ug/snlu032a/snlu032a.pdf) 

    I don't believe it is really necessary to isolate the supplies/grounds as long as the supply noise can be kept below 20mVpp. If noise is a concern then ferrite beads are recommended, as well as separate power/ground planes for PLL_VCC and PLL_GND. They should also use the same bypass capacitor scheme as the EVM on each supply pin.

    For RxOUT serial resistors, please reference section 4.3 on page 11 of the above EVM guide. These resistors are optional in case customers want to connect the outputs to the 50ohm inputs on an oscilloscope.

    Regards,
    I.K.