Analog Devices AD9361 User Manual

UG-570 AD9361 Reference Manual
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BBPLL VCO
The BBPLL VCO is a multiband ring oscillator with Kv of
550 MHz/V that requires a frequency calibration before
operation. The calibration is configured and run with the
ad9361_bbpll_set_rate function.
Figure 7 is a block diagram of the BBPLL. The reference
frequency for the loop is the output of the reference scaler
block, which is identical to, but independent from the reference
scaler blocks for the RFPLLs. The reference block is configured
to buffer, multiply, or divide the device reference frequency
before passing to the to the BBPLL phase detector. For best
performance, it is recommended that the BBPLL reference
scaler block be configured such that the resulting BBPLL F
REF
is
between 35 MHz to 70 MHz.
Fig
ure 7. BBPLL Block Diagram
F
REF
÷2
÷4
UP
DWN
PFD
LPF
F
OUT
F
VCO
715MHz TO 1430MHz
N ÷ (N + 1)
DSM
MODULUS = 2088960
FRACTIONAL WORD
INTEGER WORD
×2
11668-008
Rev. A

Analog Devices AD9361 Specifications

General

Brand	Analog Devices
Model	AD9361
Category	Motherboard
Language	English