• State TI Thinks Resolved
  • Locked Locked
  • Replies 1 reply
  • Answers 1 answer
  • Subscribers 21 subscribers
  • Views 329 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.

LMX2594: SYSREF DC coupling

daniele sassaroli
Intellectual 650 points
Part Number: LMX2594

Hi,

I'm using a LMX2594 to generate a clock and a Sysref signal. I'm generationg a
burst of 5 sysref impulses.  In this case the AC coupling is not a good idea and I want to use the DC
coupling. The Rx is a PI6C5916004ZHIE and the maximum Vih is VDD-0.9 = 2.4V.

I don't connected directly the RF_outB of the LMX2594 to the Rx. Can I reduce the 
OutB high level of the LMX2594 removing the Cap and inserting a resistor?
 

Do you have any suggestion to adapt the 2.3-3.3V to the input levels of the PI6C5916004ZHIE?

Thanks you in advance for your attention.

  • 0
    TI__Genius 11900 points

    Hello Daniele,

    Have you tried changing the output power level to see if a lower power settings fits your requirements?

    Update (8/12): You cannot meet Vih < 2.4 V if you DC couple the output. The DC bias of the output increases with decrease in power setting. At PWR = 31 the DC bias I measured was 2 V, however after adding on the signal swing the Vih exceeds the requirement. At PWR = 15 DC bias is 2.5 V and after adding the signal swing still exceeds the requirement.

    Thanks,

    Vibhu