ADF4360-2_15 Datasheet, PDF (17/24 Pages) Analog Devices – Integrated Synthesizer and VCO

Data Sheet
Hardware Power-Up/Power-Down
If the ADF4360-2 is powered down via the hardware (using the
CE pin) and powered up again without any change to the N
counter register during power-down, the part locks at the
correct frequency because it is already in the correct frequency
band. The lock time depends on the value of capacitance on the
CN pin, which is <5 ms for 10 µF capacitance. The smaller
capacitance of 440 nF on this pin enables lock times of <600 µs.
The N counter value cannot be changed while it is in power-
down because it may not lock to the correct frequency on
power-up. If it is updated, the correct programming sequence
for the part after power-up is to the R counter latch, followed by
the control latch, and finally the N counter latch, with the
required interval between the control latch and N counter latch,
as described in the Initial Power-Up section.
ADF4360-2
Software Power-Up/Power-Down
If the ADF4360-2 is powered down via the software (using the
control latch) and powered up again without any change to the
N counter latch during power-down, the part locks at the
correct frequency because it is already in the correct frequency
band. The lock time depends on the value of capacitance on the
CN pin, which is <5 ms for 10 µF capacitance. The smaller
capacitance of 440 nF on this pin enables lock times of <600 µs.
The N counter value cannot be changed while the part is in
power-down because it may not lock to the correct frequency
on power-up. If it is updated, the correct programming
sequence for the parts after power-up is to the R counter latch,
followed by the control latch, and finally the N counter latch,
with the required interval between the control latch and N
counter latch, as described in the Initial Power-Up section.
Rev. C | Page 17 of 24