QWe are using a ADF4002BRU and have noticed that the device works with RFin
driven at 0dBM and upto 500MHz,
although it only specified for operation up to 400MHz. I noticed the Rev B data
sheet “Figure 5. RF
Input Sensitivity” extends to 500MHz typical.
We are interested to know:
1. Is operation above the specified frequency a repeatable/guaranteed feature
of the ADF4002?
2. What are the best operating conditions help ensure the RF input functions at
this higher frequency?
3. Is there any test data to verify what we are seeing that it is
AIf you use the device beyond 400MHz the N counter will simply stop working
because the frequency will be too fast for the CMOS counter.
Sorry if Figure 5 has caused some confusion and this demonstrates the result
for perhaps 1-3 devices. Furthermore the ADF4002 has been characterised over
temperature for an RFin of upto 400Mhz only and hence cannot be guaranteed to
work beyond 400MHz.