Using ADF4108 RFin at a frequency less than 1Ghz minimum stated in datasheet?

Document created by analog-archivist Employee on Feb 23, 2016
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The ADF4108 Datasheet states a minimum frequency of 1GHz and a slew rate of
320V/us or more below 1 GHz.

Can I feed the ADF4108 with a sine wave 0.5 to 1v pk2pk at 330 MHz to get the
PLL operational ?

will the ADF4108 be operational at 330 MHz and RFin ~ 0.5 to 1Vpp?


The max input across the RF inputs must be limited to +5dbm= differentially =
+/-0.562 pk to pk  or 1.125 single ended (Vp = 0.562) .

As the slew rate of a sinewave = 2*pi*f*V(peak), then with a peak value of
0.5Volts, and an input of 330Mhz, you will get a slew rate of:

2 x 3.14159265 x 0.5 x 330 x 10^6 = 1036.73 x 10^6 Volts per sec = 1035 v/usec .

Therefore, using a RFin with a frequency of 330MHz and with amplitude of ~ 0.5
to 1Vpp is fine.