I am conused withe the descriotion in the ADF4112 datasheet. Could anyoneone clarify and give me any advice?
In the ADF4110/ADF4111/ADF4112/ADF4113 Rev,C datasheet on page 3, the Reference Input Sensitivity is specified as 0.4/AVDD V p-p min/max for AVDD = 3.3 V and 3.0/AVDD V p-p min/max for AVDD = 5 V. Isn't it 0.3/AVDD V p-p min/max for AVDD = 5 V??
The meaning of this is that we have to put the Reference level more than 0.4Vp-p and less than 3.3 Vp-p for AVDD 3.3V. Am I correct?
If we increase the AVDD to 5V, the device capacity should icrease. So it should be more than 0.3Vp-p and less than 5 Vp-p for AVDD 5V.
I am also confused with the description on page 7.
REF IN: Reference Input. This is a CMOS input with a nominal threshold of VDD/2,
I put 1Vp-p (0 to 1V) for AVDD = 5 V as 10MHz Reference. It does not reach the threshhold as 2.5V. But It is working fine.