EVAL-ADF4007EBZ1

Hello,

I tried to give the eval board (EV-ADF4007EBZ1) two RF signals (square wave), one way as a REFIN, one way is RFIN. At the PFD, REFIN /2 is being compared to RFIN /8 .

For graph 1, REFIN = 12 MHz.  RFIN =48 MHz.  At the PFD, 6MHz(REFIN) is being compared to 6.25 MHz (RFIN).

For graph 2, REFIN = 12 MHz.  RFIN =40 MHz.  At the PFD, 6MHz(REFIN) is being compared to 5.25 MHz (RFIN).

Compared to graph 1, I found that when the REFIN frequency is higher than RFIIN, the CP output moved up 5V.

 Thanks,

Ning