ADF4350BCPZ Analog Devices Inc, ADF4350BCPZ Datasheet - Page 25

• Manufacturer Part Number: ADF4350BCPZ
• Description: F-N With High Performance Integrated VCO
• Manufacturer: Analog Devices Inc
• Type: Fanout Distribution, Fractional N, Integer N, Clock/Frequency Synthesizer (RF)r

Specifications of ADF4350BCPZ

• Design Resources: Broadband Low EVM Direct Conversion Transmitter (CN0134) Broadband Low EVM Direct Conversion Transmitter Using LO Divide-by-2 Modulator (CN0144) Using low noise linear drop-out regulators to power wideband PLL & VCO IC's (CN0147)
• Pll: Yes
• Input: CMOS
• Output: Clock
• Number Of Circuits: 1
• Ratio - Input:output: 1:3
• Differential - Input:output: No/No
• Frequency - Max: 4.4GHz
• Divider/multiplier: Yes/Yes
• Voltage - Supply: 3 V ~ 3.6 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 32-LFCSP
• Frequency-max: 4.4GHz
• Frequency: 4.4GHz
• Supply Voltage Range: 3V To 3.6V
• Digital Ic Case Style: LFCSP
• No. Of Pins: 32
• Operating Temperature Range: -40°C To +85°C
• Clock External Input: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

APPLICATIONS INFORMATION
DIRECT CONVERSION MODULATOR
Direct conversion architectures are increasingly being used to
implement base station transmitters. Figure 34 shows how Analog
Devices, Inc., parts can be used to implement such a system.
The circuit block diagram shows the AD9761 TxDAC® being
used with the ADL5375. The use of dual integrated DACs, such
as the AD9788 with its specified ±0.02 dB and ±0.001 dB gain
and offset matching characteristics, ensures minimum error
contribution (over temperature) from this portion of the
signal chain.
The local oscillator (LO) is implemented using the ADF4350.
The low-pass filter was designed using ADIsimPLL™ for a channel
spacing of 200 kHz and a closed-loop bandwidth of 35 kHz.
FREF
IN
4.7kΩ
1nF
1nF
51Ω
29
22
1
2
3
MODULATED
DIGITAL
DATA
16
REF
CLK
DATA
LE
R
CP
V
SET
V
VCO
8
VCO
GND
IN
17
SD
DV
28
GND
31
DD
2kΩ
REFIO
AV
FSADJ
AGND
10
DD
9
V
CE
4
11 18 21
DD
ADF4350
A
GNDVCO
PDB
AD9761
TxDAC
26
RF
V
10pF
6
P
D
GND
27
SDV
QOUTA
QOUTB
32
IOUTA
IOUTB
DD
TEMP VCOM V
19
MUXOUT
0.1µF 10pF
DETECT
LOCK
30
Figure 34. Direct Conversion Modulator
51Ω
51Ω
23
RF
RF
RF
RF
LD
CP
25
OUT
OUT
OUT
OUT
V
TUNE
OUT
SW
REF
24
B+
B–
A+
A–
Rev. 0 | Page 25 of 28
51Ω
51Ω
0.1µF 10pF
14
15
12
13
20
7
5
LOW-PASS
LOW-PASS
V
VCO
2700pF
FILTER
FILTER
3.9nH
0.1µF
3.9nH
The LO ports of the ADL5375 can be driven differentially from
the complementary RF
This gives better performance than a single-ended LO driver
and eliminates the use of a balun to convert from a single-ended
LO input to the more desirable differential LO input for the
ADL5375. The typical rms phase noise (100 Hz to 5 MHz)
of the LO in this configuration is 0.61°rms.
The AD8349 accepts LO drive levels from −10 dBm to 0 dBm.
The optimum LO power can be software programmed on the
ADF4350, which allows levels from −4 dBm to +5 dBm from
each output.
The RF output is designed to drive a 50 Ω load, but must be
ac-coupled, as shown in Figure 34. If the I and Q inputs are
driven in quadrature by 2 V p-p signals, the resulting output
power from the modulator is approximately 2 dBm.
360Ω
680Ω
39nF
1200pF
1nF
1nF
QBBN
QBBP
IBBP
IBBN
LOIN
LOIP
OUT
A and RF
QUADRATURE
SPLITTER
PHASE
OUT
B outputs of the ADF4350.
ADL5375
ADF4350
RFO
DSOP