Integrated Synthesizer and VCO
FEATURES
Output frequency range: 1450 MHz to 1750 MHz
Divide-by-2 output
3.0 V to 3.6 V power supply
1.8 V logic compatibility
Integer-N synthesizer
Programmable dual-modulus prescaler 8/9, 16/17, 32/33
Programmable output power level
3-wire serial interface
Analog and digital lock detect
Hardware and software power-down mode
APPLICATIONS
Wireless handsets (DECT, GSM, PCS, DCS, WCDMA)
Test equipment
Wireless LANs
CATV equipment
FUNCTIONAL BLOCK DIAGRAM
AV
DD
ADF4360-4
REF
CLK
DATA
IN
LE
14-BIT R
COUNTER
24-BIT
DATA REGISTER
24-BIT
FUNCTION
LATCH
DV
DD
ADF4360-4
GENERAL DESCRIPTION
The ADF4360-4 is a fully integrated integer-N synthesizer
and voltage-controlled oscillator (VCO). The ADF4360-4 is
designed for a center frequency of 1600 MHz. In addition, a
divide-by-2 option is available, whereby the user gets an RF
output of between 725 MHz and 875 MHz.
Control of all the on-chip registers is through a simple 3-wire
interface. The device operates with a power supply ranging from
3.0 V to 3.6 V and can be powered down when not in use.
CE
R
SET
MUXOUT
CP
V
VCO
V
TUNE
C
C
C
N
LOCK
DETECT
PHASE
COMPARATOR
MULTIPLEXER
CHARGE
PUMP
MUTE
INTEGER
REGISTER
13-BIT B
COUNTER
PRESCALER
P/P+1
N = (BP + A)
Rev. A
Information furnished by Analog Devices is believed to be accurate and reliable.
However, no responsibility is assumed by Analog Devices for its use, nor for any
infringements of patents or other rights of third parties that may result from its use.
Specifications subject to change without notice. No license is granted by implication
or otherwise under any patent or patent rights of Analog Devices. Trademarks and
registered trademarks are the property of their respective owners.
LOAD
LOAD
5-BIT A
COUNTER
AGND DGND CPGND
MULTIPLEXER
Figure 1.
RF
A
OUT
RF
OUT
04438-001
B
DIVSEL = 1
DIVSEL = 2
VCO
CORE
OUTPUT
STAGE
÷2
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781.329.4700
www.analog.com
Fax: 781.326.8703 © 2004 Analog Devices, Inc. All rights reserved.
ADF4360-4
TABLE OF CONTENTS
Specifications..................................................................................... 3
VCO ............................................................................................. 10
Timing Characteristics..................................................................... 5
Absolute Maximum Ratings............................................................ 6
Transis t o r Cou nt ........................................................................... 6
ESD Caution.................................................................................. 6
Pin Configuration and Functional Descriptions.......................... 7
Typical Performance Characteristics............................................. 8
Circuit Description........................................................................... 9
Reference Input Section............................................................... 9
Prescaler (P/P + 1)........................................................................ 9
A and B Counters ......................................................................... 9
R Counter ...................................................................................... 9
PFD and Charge Pump................................................................ 9
MUXOUT and Lock Detect...................................................... 10
Input Shift Register..................................................................... 10
Output Stage................................................................................ 11
Latch Structure ........................................................................... 12
Power-Up..................................................................................... 16
Control Latch.............................................................................. 18
N Counter Latch......................................................................... 19
R Counter Latch ......................................................................... 19
Applications..................................................................................... 20
Direct Conversion Modulator .................................................. 20
Fixed Frequency LO ................................................................... 21
Interfacing ................................................................................... 21
PCB Design Guidelines for Chip Scale Package........................... 22
Output Matching........................................................................ 22
Outline Dimensions....................................................................... 23
Ordering Guide .......................................................................... 23
REVISION HISTORY
12/04—Rev. 0 to Rev. A
Updated Format..................................................................Universal
Changes to Specifications................................................................ 3
Changes to Timing Characteristics................................................ 5
Changes to the Power-Up Section................................................ 16
Added Table 10 ............................................................................... 16
Added Figure 16.............................................................................. 16
Changes to Ordering Guide.......................................................... 23
Updated the Outline Dimensions................................................. 23
11/03—Revision 0: Initial Version
Rev. A | Page 2 of 24
ADF4360-4
SPECIFICATIONS
AVDD = DVDD = V
Table 1.
Parameter B Version Unit Conditions/Comments
REFIN CHARACTERISTICS
REFIN Input Frequency 10/250 MHz min/max
REFIN Input Sensitivity 0.7/AV
0 to AVDD V max CMOS compatible.
REFIN Input Capacitance 5.0 pF max
REFIN Input Current ±100 µA max
PHASE DETECTOR
Phase Detector Frequency2 8 MHz max
CHARGE PUMP
ICP Sink/Source3 With R
High Value 2.5 mA typ
Low Value 0.312 mA typ
R
Range 2.7/10 kΩ
SET
ICP 3-State Leakage Current 0.2 nA typ
Sink and Source Current Matching 2 % typ 1.25 V ≤ VCP ≤ 2.5 V.
ICP vs. VCP 1.5 % typ 1.25 V ≤ VCP ≤ 2.5 V.
ICP vs. Temperature 2 % typ VCP = 2.0 V.
LOGIC INPUTS
V
, Input High Voltage 1.5 V min
INH
V
, Input Low Voltage 0.6 V max
INL
I
, Input Current ±1 µA max
INH/IINL
CIN, Input Capacitance 3.0 pF max
LOGIC OUTPUTS
VOH, Output High Voltage DVDD – 0.4 V min CMOS output chosen.
IOH, Output High Current 500 µA max
VOL, Output Low Voltage 0.4 V max IOL = 500 µA.
POWER SUPPLIES
AVDD 3.0/3.6 V min/V max
DVDD AV
V
AV
VCO
4
AI
DD
4
DI
DD
, 5
4
I
VCO
4
I
RFOUT
Low Power Sleep Mode4 7 µA typ
RF OUTPUT CHARACTERISTICS5
VCO Output Frequency 1450/1750 MHz min/max I
VCO Sensitivity 50 MHz/V typ
Lock Time
Frequency Pushing (Open Loop) 6 MHz/V typ
Frequency Pulling (Open Loop) 15 kHz typ Into 2.00 VSWR load.
Harmonic Content (Second) −19 dBc typ
Harmonic Content (Third) −37 dBc typ
Output Power
Output Power Variation ±3 dB typ For tuned loads, see the Output Matching section.
VCO Tuning Range 1.25/2.50 V min/max
VCO
6
5, 7
1
= 3.3 V ± 10%; AGND = DGND = 0 V; TA = T
DD
DD
DD
10 mA typ
2.5 mA typ
24.0 mA typ I
3.5–11.0 mA typ RF output stage is programmable.
400 µs typ To within 10 Hz of final frequency.
−13/−4 dBm typ Programmable in 3 dB steps. See Table 7.
MIN
to T
, unless otherwise noted.
MAX
For f < 10 MHz, use dc-coupled CMOS compatible
square wave, slew rate > 21 V/µs.
V p-p min/max AC-coupled.
= 4.7 kΩ.
SET
= 15 mA.
CORE
= 15 mA.
CORE
Rev. A | Page 3 of 24
ADF4360-4
Parameter B Version Unit Conditions/Comments
NOISE CHARACTERISTICS5
VCO Phase-Noise Performance8 −111 dBc/Hz typ @ 100 kHz offset from carrier.
−133 dBc/Hz typ @ 1 MHz offset from carrier.
−141 dBc/Hz typ @ 3 MHz offset from carrier.
−147 dBc/Hz typ @ 10 MHz offset from carrier.
Synthesizer Phase-Noise Floor9 −172 dBc/Hz typ @ 25 kHz PFD frequency.
−163 dBc/Hz typ @ 200 kHz PFD frequency.
−147 dBc/Hz typ @ 8 MHz PFD frequency.
In-Band Phase Noise
RMS Integrated Phase Error12 0.56 Degrees typ 100 Hz to 100 kHz.
Spurious Signals due to PFD Frequency
Level of Unlocked Signal with MTLD Enabled −48 dBm
1
Operating temperature range is –40°C to +85°C.
2
Guaranteed by design. Sample tested to ensure compliance.
3
ICP is internally modified to maintain constant loop gain over the frequency range.
4
TA = 25°C; AVDD = DVDD = V
5
These characteristics are guaranteed for VCO core power = 15 mA.
6
Jumping from 1.45 GHz to 1.75 GHz. PFD frequency = 200 kHz; loop bandwidth = 10 kHz.
7
Using 50 Ω resistors to V
8
The noise of the VCO is measured in open-loop conditions.
9
The synthesizer phase-noise floor is estimated by measuring the in-band phase noise at the output of the VCO and subtracting 20 log N (where N is the N divider value).
10
The phase noise is measured with the EVAL-ADF4360-xEB1 Evaluation Board and the HP8562E Spectrum Analyzer. The spectrum analyzer provides the REFIN for the
synthesizer; offset frequency = 1 kHz.
11
f
= 10 MHz; f
REFIN
12
f
= 10 MHz; f
REFIN
13
The spurious signals are measured with the EVAL-ADF4360-xEB1 Evaluation Board and the HP8562E Spectrum Analyzer. The spectrum analyzer provides the REFIN for
the synthesizer; f
10, 11
11, 13
= 3.3 V; P = 32.
VCO
into a 50 Ω load. For tuned loads, see the section. Output Matching
VCO
= 200 kHz; N = 8000; Loop B/W = 10 kHz.
PFD
= 1 MHz; N = 1600; Loop B/W = 25 kHz.
PFD
= 10 MHz @ 0 dBm.
REFOUT
−85 dBc/Hz typ @ 1 kHz offset from carrier.
−65 dBc typ
Rev. A | Page 4 of 24
ADF4360-4
K
TIMING CHARACTERISTICS
AVDD = DVDD = V
Table 2.
Parameter Limit at T
t1 20 ns min LE Setup Time
t2 10 ns min DATA to CLOCK Setup Time
t3 10 ns min DATA to CLOCK Hold Time
t4 25 ns min CLOCK High Duration
t5 25 ns min CLOCK Low Duration
t6 10 ns min CLOCK to LE Setup Time
t7 20 ns min LE Pulse Width
1
See the section for the recommended power-up procedure for this device. Power-Up
= 3.3 V ± 10%; AGND = DGND = 0 V; 1.8 V and 3 V logic levels used; TA = T
VCO
MIN
1
to T
MIN
to T
(B Version) Unit Test Conditions/Comments
MAX
, unless other wise noted.
MAX
CLOC
DATA
t
2
DB23 (MSB) DB22 DB2
LE
t
1
LE
t
t
4
3
t
5
DB1
(CONTROL BIT C2)
DB0 (LSB)
(CONTROL BIT C1)
t
6
t
7
04438-002
Figure 2. Timing Diagram
Rev. A | Page 5 of 24
ADF4360-4
ABSOLUTE MAXIMUM RATINGS
TA = 25°C, unless otherwise noted.
Table 3.
Parameter Rating
AVDD to GND
AVDD to DVDD −0.3 V to +0.3 V
V
to GND −0.3 V to +3.9 V
VCO
V
to AVDD −0.3 V to +0.3 V
VCO
Digital I/O Voltage to GND −0.3 V to VDD + 0.3 V
Analog I/O Voltage to GND −0.3 V to VDD + 0.3 V
REFIN to GND −0.3 V to VDD + 0.3 V
Operating Temperature Range
Maximum Junction Temperature 150°C
CSP θJA Thermal Impedance
(Paddle Soldered) 50°C/W
(Paddle Not Soldered) 88°C/W
Lead Temperature, Soldering
Vapor Phase (60 sec) 215°C
Infrared (15 sec) 220°C
1
−0.3 V to +3.9 V
1
GND = AGND = DGND = 0 V.
Stresses above those listed under Absolute Maximum Ratings
may cause permanent damage to the device. This is a stress rating only; functional operation of the device at these or any
other conditions above those indicated in the operational sections of this specification is not implied. Exposure to absolute
maximum rating conditions for extended periods may affect
device reliability.
This device is a high performance RF integrated circuit with an
ESD rating of <1 kV and it is ESD sensitive. Proper precautions
should be taken for handling and assembly.
TRANSISTOR COUNT
12543 (CMOS) and 700 (Bipolar)
ESD CAUTION
ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily accumulate on the
human body and test equipment and can discharge without detection. Although this product features proprietary ESD protection circuitry, permanent damage may occur on devices subjected to high energy electrostatic
discharges. Therefore, proper ESD precautions are recommended to avoid performance degradation or loss of
functionality.
Rev. A | Page 6 of 24
ADF4360-4
T
PIN CONFIGURATION AND FUNCTIONAL DESCRIPTIONS
DD
21
PIN 1
IDENTIFIER
ADF4360-4
TOP VIEW
(Not to Scale)
AGND8AGND9AGND10AGND
MUXOU
20LE19
11
18
DATA
CLK
17
REF
16
IN
DGND
15
C
14
N
R
13
SET
12
C
C
04438-003
CPGND
AV
AGND
RF
OUT
RF
OUT
V
VCO
CP24CE23AGND22DV
1
2
DD
3
A
4
B
5
6
7
TUNE
V
Figure 3. Pin Configuration
Table 4. Pin Functional Descriptions
Pin No. Mnemonic Description
1 CPGND Charge Pump Ground. This is the ground return path for the charge pump.
2 AVDD
Analog Power Supply. This ranges from 3.0 V to 3.6 V. Decoupling capacitors to the analog ground plane
should be placed as close as possible to this pin. AV
must have the same value as DVDD.
DD
3, 8 to 11, 22 AGND Analog Ground. This is the ground return path of the prescaler and VCO.
4 RF
OUT
A
VCO Output. The output level is programmable from −4 dBm to −13 dBm. See the Output Matching section for
a description of the various output stages.
5 RF
OUT
B
VCO Complementary Output. The output level is programmable from −4 dBm to −13 dBm. See the Output
Matching section for a description of the various output stages.
6 V
7 V
VCO
Control Input to the VCO. This voltage determines the output frequency and is derived from filtering the CP output voltage.
TUNE
Power Supply for the VCO. This ranges from 3.0 V to 3.6 V. Decoupling capacitors to the analog ground plane
should be placed as close as possible to this pin. V
must have the same value as AVDD.
VCO
12 CC Internal Compensation Node. This pin must be decoupled to ground with a 10 nF capacitor.
13 R
14 C
SET
N
Connecting a resistor between this pin and CP
synthesizer. The nominal voltage potential at the R
I
where R
CPmax
SET
75.11
=
R
SET
= 4.7 kΩ, I
CPmax
= 2.5 mA.
Internal Compensation Node. This pin must be decoupled to V
sets the maximum charge pump output current for the
GND
pin is 0.6 V. The relationship between ICP and R
SET
with a 10 µF capacitor.
VCO
is
SET
15 DGND Digital Ground.
16 REFIN
Reference Input. This is a CMOS input with a nominal threshold of V
/2 and a dc equivalent input resistance of
DD
100 kΩ. See Figure 10. This input can be driven from a TTL or CMOS crystal oscillator or it can be ac-coupled.
17 CLK
Serial Clock Input. This serial clock is used to clock in the serial data to the registers. The data is latched into the
24-bit shift register on the CLK rising edge. This input is a high impedance CMOS input.
18 DATA
Serial Data Input. The serial data is loaded MSB first with the two LSBs being the control bits. This input is a
high impedance CMOS input.
19 LE
Load Enable, CMOS Input. When LE goes high, the data stored in the shift registers is loaded into one of the
four latches, and the relevant latch is selected using the control bits.
20 MUXOUT
This multiplexer output allows either the lock detect, the scaled RF, or the scaled reference frequency to be
accessed externally.
21 DVDD
23 CE
Digital Power Supply. This ranges from 3.0 V to 3.6 V. Decoupling capacitors to the digital ground plane should
be placed as close as possible to this pin. DV
must have the same value as AVDD.
DD
Chip Enable. A logic low on this pin powers down the device and puts the charge pump into three-state mode.
Taking the pin high powers up the device depending on the status of the power-down bits.
24 CP Charge Pump Output. When enabled, this provides ± ICP to the external loop filter, which in turn drives the internal VCO.
Rev. A | Page 7 of 24
ADF4360-4
TYPICAL PERFORMANCE CHARACTERISTICS
0
–10
–20
–30
–40
–50
–60
–70
–80
–90
–100
–110
–120
OUTPUT POWER (dB)
–130
–140
–150
–160
–170
1k 10M1M100k10k
1
2
FREQUENCY OFFSET (Hz)
Figure 4. Open-Loop VCO Phase Noise
3
4
04438-004
0
VDD = 3V, V
–10
I
= 2.5mA
CP
PFD FREQUENCY = 200kHz
–20
LOOP BANDWIDTH = 10kHz
RES. BANDWIDTH = 30Hz
–30
VIDEO BANDWIDTH = 30Hz
SWEEP = 1.9 SECONDS
AVERAGES = 10
–40
–50
–60
–70
OUTPUT POWER (dB)
–80
–90
–2kHz –1kHz 1600MHz 1kHz 2kHz
VCO
= 3V
–87.2dBc/Hz
04438-007
Figure 7. Close-In Phase Noise at 1600 MHz (200 kHz Channel Spacing)
–70
–75
–80
–85
–90
–95
–100
–105
–110
–115
–120
–125
OUTPUT POWER (dB)
–130
–135
–140
–145
–150
100 10M1M100k10k1k
FREQUENCY OFFSET (Hz)
04438-005
Figure 5. VCO Phase Noise, 1600 MHz, 200 kHz PFD, 10 kHz Loop Bandwidth
–70
–75
–80
–85
–90
–95
–100
–105
–110
–115
–120
–125
OUTPUT POWER (dB)
–130
–135
–140
–145
–150
100 10M1M100k10k1k
FREQUENCY OFFSET (Hz)
04438-006
Figure 6. VCO Phase Noise, 800 MHz,
Divide-by-2 Enabled, 200 kHz PFD, 10 kHz Loop Bandwidth
0
VDD = 3V, V
–10
I
= 2.5mA
CP
PFD FREQUENCY = 200kHz
–20
LOOP BANDWIDTH = 10kHz
RES. BANDWIDTH = 3kHz
–30
VIDEO BANDWIDTH = 3kHz
SWEEP = 14 ms
AVERAGES = 100
–40
–50
–60
–70
OUTPUT POWER (dB)
–80
–90
–200kHz –100kHz 1600MHz 100kHz 200kHz
VCO
= 3V
Figure 8. Reference Spurs at 1600 MHz
(200 kHz Channel Spacing, 10 kHz Loop Bandwidth)
0
VDD = 3V, V
I
= 2.5mA
–10
CP
PFD FREQUENCY = 1MHz
LOOP BANDWIDTH = 25kHz
–20
RES. BANDWIDTH = 30kHz
VIDEO BANDWIDTH = 30kHz
–30
SWEEP = 50 ms
AVERAGES = 100
–40
–50
–60
–70
OUTPUT POWER (dB)
–80
–90
–1MHz –0.5MHz 1600MHz 0.5MHz 1MHz
VCO
= 3V
Figure 9. Reference Spurs at 1600 MHz
(1 MHz Channel Spacing, 25 kHz Loop Bandwidth)
–74.3dBc
04438-008
–77.5dBc/Hz
04438-009
Rev. A | Page 8 of 24
ADF4360-4
C
T
CIRCUIT DESCRIPTION
REFERENCE INPUT SECTION
The reference input stage is shown in Figure 10. SW1 and SW2
are normally closed switches. SW3 is normally open. When
power-down is initiated, SW3 is closed, and SW1 and SW2 are
opened. This ensures that there is no loading of the REF
IN
pin
on power-down.
POWER-DOWN
CONTROL
FROM VCO
N = BP + A
PRESCALER
MODULUS
CONTROL
P/P+1
13-BIT B
COUNTER
LOAD
LOAD
5-BIT A
COUNTER
TO PFD
100kΩ
NC
REF
SW1
NO
SW2
SW3
IN
NC
BUFFER
TO R COUNTER
04438-010
Figure 10. Reference Input Stage
PRESCALER (P/P + 1)
The dual-modulus prescaler (P/P + 1), along with the A and B
counters, enables the large division ratio, N, to be rea lized
(N = BP + A). The dual-modulus prescaler, operating at CML
levels, takes the clock from the VCO and divides it down to a
manageable frequency for the CMOS A and B counters. The
prescaler is programmable. It can be set in software to 8/9,
16/17, or 32/33 and is based on a synchronous 4/5 core. There is
a minimum divide ratio possible for fully contiguous output
frequencies; this minimum is determined by P, the prescaler
value, and is given by (P
2
− P).
A AND B COUNTERS
The A and B CMOS counters combine with the dual-modulus
prescaler to allow a wide range division ratio in the PLL feedback counter. The counters are specified to work when the prescaler output is 300 MHz or less. Thus, with a VCO frequency of
2.5 GHz, a prescaler value of 16/17 is valid, but a value of 8/9 is
not valid.
Pulse Swallow Function
The A and B counters, in conjunction with the dual-modulus
prescaler, make it possible to generate output frequencies that
are spaced only by the reference frequency divided by R. The
VCO frequency equation is
RfABPf
REFIN
/×]+×[=
where:
VCO
()
N DIVIDER
04438-011
Figure 11. A and B Counters
R COUNTER
The 14-bit R counter allows the input reference frequency to
be divided down to produce the reference clock to the phase
frequency detector (PFD). Division ratios from 1 to 16,383 are
allowed.
PFD AND CHARGE PUMP
The PFD takes inputs from the R counter and N counter
(N = BP + A) and produces an output proportional to the phase
and frequency difference between them. Figure 12 is a simplified schematic. The PFD includes a programmable delay element that controls the width of the antibacklash pulse. This
pulse ensures that there is no dead zone in the PFD transfer
function and minimizes phase noise and reference spurs. Two
bits in the R counter latch, ABP2 and ABP1, control the width of
the pulse (see Table 9).
V
P
CHARGE
PUMP
HI
R DIVIDER
HI
N DIVIDER
Q1D1
U1
CLR1
PROGRAMMABLE
ABP1 ABP2
CLR2
Q2D2
U2
UP
DELAY
DOWN
U3
CPGND
CP
f
is the output frequency of the VCO.
VCO
P is the preset modulus of the dual-modulus prescaler (8/9,
R DIVIDER
16/17, and so on).
B is the preset divide ratio of the binary 13-bit counter (3 to 8191).
N DIVIDER
A is the preset divide ratio of the binary 5-bit swallow counter (0 to 31).
f
is the external reference frequency oscillator.
REFIN
Rev. A | Page 9 of 24
P OUTPU
Figure 12. PFD Simplified Schematic and Timing (In Lock)
04438-012
ADF4360-4
MUXOUT AND LOCK DETECT
The output multiplexer on the ADF4360 family allows the user
to access various internal points on the chip. The state of
MUXOUT is controlled by M3, M2, and M1 in the function
latch. The full truth table is shown in Table 7. Figure 13 shows
the MUXOUT section in block diagram form.
Lock Detect
MUXOUT can be programmed for two types of lock detect:
digital and analog. Digital lock detect is active high. When LDP
in the R counter latch is set to 0, digital lock detect is set high
when the phase error on three consecutive phase detector cycles
is less than 15 ns.
Table 5. C2 and C1 Truth Table
Control Bits
C2 C1 Data Latch
0 0 Control Latch
0 1 R Counter
1 0 N Counter (A and B)
1 1 Test Mode Latch
VCO
The VCO core in the ADF4360 family uses eight overlapping
bands, as shown in Figure 14, to allow a wide frequency range to
be covered without a large VCO sensitivity (K
poor phase noise and spurious performance.
) and resultant
V
With LDP set to 1, five consecutive cycles of less than 15 ns
phase error are required to set the lock detect. It stays set high
until a phase error greater than 25 ns is detected on any
subsequent PD cycle.
The N-channel open-drain analog lock detect should be operated with an external pull-up resistor of 10 kΩ nominal. When a
lock has been detected, the output is high with narrow lowgoing pulses.
DV
DD
ANALOG LOCK DETECT
DIGITAL LOCK DETECT
R COUNTER OUTPUT
N COUNTER OUTPUT
SDOUT
CONTROLMUX
Figure 13. MUXOUT Circuit
MUXOUT
DGND
INPUT SHIFT REGISTER
The ADF4360 family’s digital section includes a 24-bit input
shift register, a 14-bit R counter, and an 18-bit N counter,
comprised of a 5-bit A counter and a 13-bit B counter. Data is
clocked into the 24-bit shift register on each rising edge of CLK.
The data is clocked in MSB first. Data is transferred from the
shift register to one of four latches on the rising edge of LE. The
destination latch is determined by the state of the two control
bits (C2, C1) in the shift register. The two LSBs are DB1 and
DB0, as shown in Figure 2.
The truth table for these bits is shown in Table 5. Table 6 shows
a summary of how the latches are programmed. Note that the
test mode latch is used for factory testing and should not be
programmed by the user.
04438-013
The correct band is chosen automatically by the band select
logic at power-up or whenever the N counter latch is updated. It
is important that the correct write sequence be followed at
power-up. This sequence is
1.
R counter latch
Control latch
2.
3.
N counter latch
During band s elect, which takes five PFD cycles, the VCO V
TUNE
is disconnected from the output of the loop filter and connected
to an internal reference voltage.
3.5
3.0
2.5
2.0
1.5
VOLTAGE (V)
1.0
0.5
0
1350 1450 1550 1650 1750 18501250 1950
Figure 14. Frequency vs. V
FREQUENCY (MHz)
, ADF4360-4
TUNE
04438-014
The R counter output is used as the clock for the band select logic
and should not exceed 1 MHz. A programmable divider is provided
at the R counter input to allow division by 1, 2, 4, or 8 and is controlled by Bits BSC1 and BSC2 in the R counter latch. Where the
required PFD frequency exceeds 1 MHz, the divide ratio should be
set to allow enough time for correct band selection.
After band select, normal PLL action resumes. The nominal value
of K
is 50 MHz/V or 25 MHz/V, if divide-by-2 operation has been
V
selected (by programming DIV2 [DB22] high in the N counter
latch). The ADF4360 family contains linearization circuitry to
minimize any variation of the product of I
and KV.
CP
Rev. A | Page 10 of 24
ADF4360-4
The operating current in the VCO core is programmable in four
steps: 5 mA, 10 mA, 15 mA, and 20 mA. This is controlled by
Bits PC1 and PC2 in the control latch.
OUTPUT STAGE
The RF
nected to the collectors of an NPN differential pair driven by
buffered outputs of the VCO, as shown in Figure 15. To allow
the user to optimize the power dissipation versus the output
power requirements, the tail current of the differential pair is
programmable via Bits PL1 and PL2 in the control latch. Four
current levels may be set: 3.5 mA, 5 mA, 7.5 mA, and 11 mA.
These levels give output power levels of −12 dBm, −9 dBm,
−6 dBm, and −3dBm, respectively, using a 50 Ω resistor to V
and ac coupling into a 50 Ω load. Alternatively, both outputs
can be combined in a 1 + 1:1 transformer or a 180° microstrip
coupler (see the Output Matching section).
A and RF
OUT
B pins of the ADF4360 family are con-
OUT
DD
If the outputs are used individually, the optimum output stage
consists of a shunt inductor to V
DD
.
Another feature of the ADF4360 family is that the supply current
to the RF output stage is shut down until the part achieves lock as
measured by the digital lock detect circuitry. This is enabled by the
mute-till-lock detect (MTLD) bit in the control latch.
RF
VCO
BUFFER/
DIVIDE BY 2
Figure 15. Output Stage ADF4360-4
ARF
OUT
OUT
B
04438-015
Rev. A | Page 11 of 24
ADF4360-4
LATCH STRUCTURE
Table 6 shows the three on-chip latches for the ADF4360 family. The two LSBs determines which latch is programmed.
Table 6. Latch Structure
CONTROL LATCH
PRESCALER
VALUE
2 SELECT
DIVIDE-BY-
RESERVED
POWER-
DB21DB22DB23
PD2P1P2
BY-2
DIVIDE-
DB21DB22DB23
CPGDIV2DIVSEL
BAND
SELECT
CLOCK
RESERVED
DB21DB22DB23
BSC2RSVRSV
CURRENT
DOWN 1
POWER-
SETTING2
DOWN 2
DB20 DB19 DB18 DB17 DB16 DB15 DB14 DB13 DB12 DB11 DB10 DB9 DB8 DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0
CURRENT
SETTING1
OUTPUT
POWER
LEVEL
LD
CP GAIN
MUTE-TILL-
CP
STATE
THREE-
PHASE
DETECTOR
POLARITY
MUXOUT
CONTROL
CORE
POWER
LEVEL
RESET
COUNTER
PC1PC2CRM1M2PDPCPCPGMTLDPL1PL2CPI1CPI2CPI3CPI4CPI5CPI6PD1 M3
CONTROL
C2 (0) C1 (0)
N COUNTER LATCH
A1A2A3A4A5B1B2B3B4B5B6B7B8B9B10B11B12B13 RSV
CONTROL
C2 (1) C1 (0)
13-BIT B COUNTER
CP GAIN
DB20 DB19 DB18 DB17 DB16 DB15 DB14 DB13 DB12 DB11 DB10 DB9 DB8 DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0
RESERVED
5-BIT A COUNTER
R COUNTER LATCH
ANTI-
BACKLASH
BIT
TEST
MODE
DB20 DB19 DB18 DB17 DB16 DB15 DB14 DB13 DB12 DB11 DB10 DB9 DB8 DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0
LOCK
DETECT
PULSE
WIDTH
PRECISION
14-BIT REFERENCE COUNTER
R1R2R3R4R5R7R8R9R10R11R12R13R14ABP1ABP2LDPTMBBSC1 R6
CONTROL
C2 (0) C1 (1)
BITS
BITS
BITS
04438-016
Rev. A | Page 12 of 24
ADF4360-4
Table 7. Control Latch
PRESCALER
VALUE
CURRENT
SETTING 2
DOWN 2
DOWN 1
POWER-
POWER-
DB20 DB19 DB18 DB17 DB16 DB15 DB14 DB13 DB12 DB11 DB10 DB9 DB8 DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0
DB21DB22DB23
CURRENT
SETTING 1
OUTPUT
POWER
LEVEL
MUTE-TILL-
LD
CP
CP GAIN
STATE
THREE-
PHASE
MUXOUT
CONTROL
POLARITY
DETECTOR
PD2P1P2
I
CPI6 CPI5 CPI4
CPI3 CPI2 CPI1 4.7kΩ
0
0
0
0
1
1
1
1
0
0
1
1
0
0
1
1
0
1
0
1
0
1
0
1
PL2 PL1 OUTPUT POWER LEVEL
0
0
1
0
0
1
CP
0.31
0.62
0.93
1.25
1.56
1.87
2.18
2.50
CURRENT POWER INTO 50Ω (USING 50Ω TO V
3.5mA
5.0mA
7.5mA
(mA)
–13dBm
–10dBm
–7dBm
–4dBm1 1 11.0mA
CPG
0
1
MUTE-TILL-LOCK DETECT
MTLD
0
DISABLED
ENABLED
1
CP
0
1
CP GAIN
CURRENT SETTING 1
CURRENT SETTING 2
PHASE DETECTOR
POLARITY
PDP
0
NEGATIVE
POSITIVE
1
CHARGE PUMP
OUTPUT
NORMAL
THREE-STATE
)
CC
CR
0
1
M3 M2 M1
001
010
011
100
101
110
111
CORE
POWER
LEVEL
RESET
COUNTER
PC2
PC1
0
0
0
1
10
11
COUNTER
OPERATION
NORMAL
R, A, B COUNTERS
HELD IN RESET
OUTPUT
THREE-STATE OUTPUT000
DIGITAL LOCK DETECT
(ACTIVE HIGH)
N DIVIDER OUTPUT
DV
DD
R DIVIDER OUTPUT
N-CHANNEL OPEN-DRAIN
LOCK DETECT
SERIAL DATA OUTPUT
DGND
PC1PC2CRM1M2PDPCPCPGMTLDPL1PL2CPI1CPI2CPI3CP14CPI5CPI6PD1 M3
CONTROL
BITS
C2 (0) C1 (0)
CORE POWER LEVEL
5mA
10mA
15mA
20mA
CE PIN PD2 PD1 MODE
0 X X ASYNCHRONOUS POWER-DOWN
1 X 0 NORMAL OPERATION
1 0 1 ASYNCHRONOUS POWER-DOWN
1 1 1 SYNCHRONOUS POWER-DOWN
P2 P1 PRESCALER VALUE
0 0 8/9
0 1 16/17
1 0 32/33
1 1 32/33
04438-017
Rev. A | Page 13 of 24
ADF4360-4
Table 8. N Counter Latch
2 SELECT
DIVIDE-BY-
DIVSEL
BY-2
DIVIDE-
DB21DB22DB23
CPGDIV2
CONTROL
CP GAIN
13-BIT B COUNTER
5-BIT A COUNTER
RESERVED
DB20 DB19 DB18 DB17 DB16 DB15 DB14 DB13 DB12 DB11 DB10 DB9 DB8 DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0
C2 (1) C1 (0)
A1A2A3A4A5B1B2B3B4B5B6B7B8B9B10B11B12B13 RSV
THIS BIT IS NOT USED
BY THE DEVICE AND
IS A DON'T CARE BIT.
A5 A4 .......... A2 A1
0 0 .......... 0 0 0
0 0 .......... 0 1 1
0 0 .......... 1 0 2
0 0 .......... 1 1 3
. . .......... . . .
. . .......... . . .
. . .......... . . .
1 1 .......... 0 0 28
1 1 .......... 0 1 29
1 1 .......... 1 0 30
1 1 .......... 1 1 31
B13 B12 B11 B3 B2 B1 B COUNTER DIVIDE RATIO
000
000
000
.. .
.. .
111
111
111
.......... 0000
.......... 0 0 1 NOT ALLOWED
.......... 0 1 0 NOT ALLOWED
.......... 1 1 1 3
.......... ... .
.......... . . . .
.......... . . . .
.......... 1111
.......... 1 0 1 8189
.......... 1 1 0 8190
.......... 1 1 1 8191
0 0 NOT ALLOWED
.. .
0 0 8188
A COUNTER
DIVIDE RATIO
BITS
DIVSEL
0
1
F4 (FUNCTION LATCH)
FASTLOCK ENABLE
DIVIDE-BY-2
DIV2
0
FUNDAMENTAL OUTPUT
DIVIDE-BY-2
1
DIVIDE-BY-2 SELECT (PRESCALER INPUT)
FUNDAMENTAL OUTPUT SELECTED
DIVIDE-BY-2 SELECTED
CP GAIN OPERATION
00
10
CHARGE PUMP CURRENT SETTING 1
IS PERMANENTLY USED
CHARGE PUMP CURRENT SETTING 2
IS PERMANENTLY USED
Rev. A | Page 14 of 24
N = BP + A; P IS PRESCALER VALUE SET IN THE CONTROL LATCH.
B MUST BE GREATER THAN OR EQUAL TO A. FOR CONTINUOUSLY
ADJACENT VALUES OF (N
×
F
), AT THE OUTPUT, N
REF
IS (P2–P).
MIN
04438-018
ADF4360-4
Table 9. R Counter Latch
RESERVED
RESERVED
THESE BITS ARE NOT
USED BY THE DEVICE
AND ARE DON'T CARE
BITS.
LOCK
DETECT
ANTI-
BACKLASH
PULSE
WIDTH
PRECISION
14-BIT REFERENCE COUNTER
BAND
SELECT
CLOCK
DB20 DB19 DB18 DB17 DB16 DB15 DB14 DB13 DB12 DB11 DB10 DB9 DB8 DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0
DB21DB22DB23
TEST
MODE
BIT
BSC2RSVRSV
TEST MODE
BIT SHOULD
BE SET TO 0
FOR NORMAL
OPERATION.
ABP2 ABP1 ANTIBACKLASH PULSE WIDTH
0 0 3.0ns
0 1 1.3ns
1 0 6.0ns
1 1 3.0ns
LDP LOCK DETECT PRECISION
0 THREE CONSECUTIVE CYCLES OF PHASE DELAY LESS THAN
1 FIVE CONSECUTIVE CYCLES OF PHASE DELAY LESS THAN
15ns MUST OCCUR BEFORE LOCK DETECT IS SET.
15ns MUST OCCUR BEFORE LOCK DETECT IS SET.
R14 R13 R12 R3 R2 R1 DIVIDE RATIO
000
000
000
...
...
111
111
111
.......... 000 0
.......... 0 1 1 2
.......... 0 1 0 3
.......... 1 0 1 4
.......... ....
.......... . . . .
.......... . . . .
.......... 111 1
.......... 1 0 1 16381
.......... 1 1 0 16382
.......... 1 1 1 16383
00 1
.. .
0 0 16380
CONTROL
BITS
C2 (0) C1 (1)R1R2R3R4R5R7R8R9R10R11R12R13R14ABP1ABP2LDPTMBBSC1 R6
BSC2 BSC1 BAND SELECT CLOCK DIVIDER
001
012
104
118
04438-019
Rev. A | Page 15 of 24
ADF4360-4
POWER-UP
Power-Up Sequence
The correct programming sequence for the ADF4360-4 after
power-up is:
1.
R counter latch
2.
Control latch
3.
N counter latch
Initial Power-Up
Initial power-up refers to programming the part after the
application of voltage to the AV
initial power-up, an interval is required between programming
the control latch and programming the N counter latch. This
interval is necessary to allow the transient behavior of the
ADF4360-4 during initial power-up to have settled.
Table 10. CN Capacitance vs. Interval and Phase Noise
CN Value Recommended Interval between Control Latch and N Counter Latch Open-Loop Phase Noise @ 10 kHz Offset
10 µF ≥ 5 ms −87 dBc
440 nF ≥ 600 µs −86 dBc
, DVDD, V
DD
, and CE pins. On
VCO
During initial power-up, a write to the control latch powers up
the part, and the bias currents of the VCO begin to settle. If
these currents have not settled to within 10% of their steadystate value, and if the N counter latch is then programmed, the
VCO may not be able to oscillate at the desired frequency,
which does not allow the band select logic to choose the correct
frequency band, and the ADF4360-4 may not achieve lock. If
the recommended interval is inserted, and the N counter latch
is programmed, the band select logic can choose the correct
frequency band, and the part locks to the correct frequency.
The duration of this interval is affected by the value of the
capacitor on the C
pin (Pin 14). This capacitor is used to
N
reduce the close-in noise of the ADF4360-4 VCO. The recommended value of this capacitor is 10 µF. Using this value
requires an interval of ≥ 5 ms between the latching in of the
control latch bits and latching in of the N counter latch bits. If a
shorter delay is required, this capacitor can be reduced. A slight
phase noise penalty is incurred by this change, which is explained further in Table 10.
POWER-UP
CLOCK
DATA
R COUNTER
LATCH DATA
LE
Figure 16. ADF4360-4 Power-Up Timing
CONTROL
LATCH DATA
N COUNTER
LATCH DATA
REQUIRED INTERVAL
CONTROL LATCH WRITE TO
N COUNTER LATCH WRITE
04438-020
Rev. A | Page 16 of 24
ADF4360-4
Hardware Power-Up/Power-Down
If the ADF4360-4 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
C
pin, which is <5 ms for 10 µF capacitance. The smaller ca-
N
pacitance of 440 nF on this pin enables lock times of <600 µs.
Software Power-Up/Power-Down
If the ADF4360-4 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
C
pin, which is <5 ms for 10 µF capacitance. The smaller ca-
N
pacitance 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.
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 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.
Rev. A | Page 17 of 24
ADF4360-4
CONTROL LATCH
With (C2, C1) = (0, 0), the control latch is programmed. Table 7
shows the input data format for programming the control latch.
Prescaler Value
In the ADF4360 family, P2 and P1 in the control latch set the
prescaler values.
Power-Down
DB21 (PD2) and DB20 (PD1) provide programmable powerdown modes.
In the programmed asynchronous power-down, the device
powers down immediately after latching a 1 into Bit PD1, with
the condition that PD2 has been loaded with a 0. In the programmed synchronous power-down, the device power-down is
gated by the charge pump to prevent unwanted frequency
jumps. Once the power-down is enabled by writing a 1 into
Bit PD1 (on the condition that a 1 has also been loaded to PD2),
the device goes into power-down on the second rising edge of
the R counter output, after LE goes high. When the CE pin is
low, the device is immediately disabled regardless of the state of
PD1 or PD2.
When a power-down is activated (either synchronous or
asynchronous mode), the following events occur:
• All active dc current paths are removed.
• The R, N, and timeout counters are forced to their load
state conditions.
• The charge pump is forced into three-state mode.
• The digital lock detect circuitry is reset.
• The RF outputs are debiased to a high impedance state.
• The reference input buffer circuitry is disabled.
• The input register remains active and capable of loading and
latching data.
Charge Pump Currents
CPI3, CPI2, and CPI1 in the ADF4360 family determine
Current Setting 1.
CPI6, CPI5, and CPI4 determine Current Setting 2. See the
truth table in Table 7.
Output Power Level
Bits PL1 and PL2 set the output power level of the VCO. See the
truth table in Table 7.
Mute-Till-Lock Detect
DB11 of the control latch in the ADF4360 family is the mute-tilllock detect bit. This function, when enabled, ensures that the RF
outputs are not switched on until the PLL is locked.
CP Gain
DB10 of the control latch in the ADF4360 family is the charge
pump gain bit. When it is programmed to a 1, Current Setting 2
is used. When it is programmed to a 0, Current Setting 1 is used.
Charge Pump Three-State
This bit puts the charge pump into three-state mode when
programmed to a 1. It should be set to 0 for normal operation.
Phase Detector Polarity
The PDP bit in the ADF4360 family sets the phase detector
polarity. The positive setting enabled by programming a 1 is
used when using the on-chip VCO with a passive loop filter or
with an active noninverting filter. It can also be set to 0. This is
required, if an active inverting loop filter is used.
MUXOUT Control
The on-chip multiplexer is controlled by M3, M2, and M1.
See the truth table in Table 7.
Counter Reset
DB4 is the counter reset bit for the ADF4360 family. When this
is 1, the R counter and the A, B counters are reset. For normal
operation, this bit should be 0.
Core Power Level
PC1 and PC2 set the power level in the VCO core. The recommended setting is 15 mA. See the truth table in Table 7.
Rev. A | Page 18 of 24
ADF4360-4
N COUNTER LATCH
With (C2, C1) = (1, 0), the N counter latch is programmed.
Table 8 shows the input data format for programming the
N counter latch.
A Counter Latch
A5 to A1 program the 5-bit A counter. The divide range is 0
(00000) to 31 (11111).
Reserved Bits
DB7 is a spare bit that is reserved. It should be programmed to 0.
B Counter Latch
B13 to B1 program the B counter. The divide range is 3
(00.....0011) to 8191 (11....111).
Overall Divide Range
The overall divide range is defined by ((P × B) + A), where P is
the prescaler value.
CP Gain
DB21 of the N counter latch in the ADF4360 family is the
charge pump gain bit. When this is programmed to 1, Current
Setting 2 is used. When programmed to 0, Current Setting 1 is used.
This bit can also be programmed through DB10 of the control
latch. The bit always reflects the latest value written to it, whether
this is through the control latch or the N counter latch.
Divide-by-2
DB22 is the divide-by-2 bit. When set to 1, the output divide-by-2
function is chosen. When it is set to 0, normal operation occurs.
Divide-by-2 Select
DB23 is the divide-by-2 select bit. When programmed to 1, the
divide-by-2 output is selected as the prescaler input. When set
to 0, the fundamental is used as the prescaler input. For example, using the output divide-by-2 feature and a PFD frequency
of 200 kHz, the user needs a value of N = 8,000 to generate
800 MHz. With the divide-by-2 select bit high, the user may
keep N = 4,000.
R COUNTER LATCH
With (C2, C1) = (0, 1), the R counter latch is programmed.
Table 9 shows the input data format for programming the
R counter latch.
R Counter
R1 to R14 set the counter divide ratio. The divide range is 1
(00......001) to 16383 (111......111).
Antibacklash Pulse Width
DB16 and DB17 set the antibacklash pulse width.
Lock Detect Precision
DB18 is the lock detect precision bit. This bit sets the number of
reference cycles with less than 15 ns phase error for entering the
locked state. With LDP at 1, five cycles are taken; with LDP at 0,
three cycles are taken.
Test Mode Bit
DB19 is the test mode bit (TMB) and should be set to 0. With
TMB = 0, the contents of the test mode latch are ignored and
normal operation occurs as determined by the contents of the
control latch, R counter latch, and N counter latch. Note that
test modes are for factory testing only and should not be programmed by the user.
Band Select Clock
These bits set a divider for the band select logic clock input. The
output of the R counter is by default the value used to clock the
band select logic, but, if this value is too high (>1 MHz), a
divider can be switched on to divide the R counter output to a
smaller value (see Table 9).
Reserved Bits
DB23 to DB22 are spare bits that are reserved. They should be
programmed to 0.
Rev. A | Page 19 of 24
ADF4360-4
APPLICATIONS
DIRECT CONVERSION MODULATOR
Direct conversion architectures are increasingly being used to
implement base station transmitters. Figure 17 shows how ADI
parts can be used to implement such a system.
The circuit block diagram shows the AD9761 TxDAC® being
used with the AD8349. The use of dual integrated DACs, such
as the AD9761 with its specified ±0.02 dB and ±0.004 dB gain
and offset matching characteristics, ensures minimum error
contribution (over temperature) from this portion of the
signal chain.
The local oscillator is implemented using the ADF4360-4. The
low-pass filter was designed using ADIsimPLL for a channel
spacing of 200 kHz and an open-loop bandwidth of 10 kHz.
The LO ports of the AD8349 can be driven differentially from
the complementary RF
A and RF
OUT
B outputs of the
OUT
ADF4360-4. This gives better performance than a single-ended
LO driver and eliminates the often necessary use of a balun to
convert from a single-ended LO input to the more desirable
differential LO inputs for the AD8349. The typical
rms phase noise (100 Hz to 100 kHz) of the LO in this
configuration is 1.09°.
The AD8349 accepts LO drive levels from −10 dBm to 0 dBm.
The optimum LO power can be software programmed on the
ADF4360-4, which allows levels from −13 dBm to −4 dBm from
each output.
The RF output is designed to drive a 50 Ω load but must be accoupled, as shown in Figure 17. 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.
MODULATED
DIGITAL
DATA
FREF
IN
1nF
SPI COMPATIBLE SERIAL BUS
10µF
REFIO
AD9761
TxDAC
FSADJ
2kΩ
V
VCO
6
DVDDAVDDCE MUXOUT
V
VCO
14
C
N
1nF1nF
16
REF
51Ω
4.7kΩ
IN
17
CLK
18
DATA
19
LE
12
C
C
13
R
SET
CPGND AGND DGND
1 3 8 9 10 11 22 15
IOUTA
IOUTB
QOUTA
QOUTB
V
DETECT
DD
ADF4360-4
LOCK
2023221
RF
RF
V
TUNE
OUT
OUT
LOW-PASS
FILTER
LOW-PASS
FILTER
7
24
CP
1nF 330pF
V
VCO
47nH 47nH
A
4
5
B
6.8kΩ
12nF
3.9kΩ
1.8pF
1.8pF
5.1nH
5.1nH
IBBP
IBBN
QBBP
QBBN
LOIP
LOIN
VPS1
PHASE
SPLITTER
AD8349
VPS2
TO
RF PA
04438-021
100pF
Figure 17. Direct Conversion Modulator
Rev. A | Page 20 of 24
ADF4360-4
FIXED FREQUENCY LO
Figure 18 shows the ADF4360-4 used as a fixed frequency LO at
1.6 GHz. The low-pass filter was designed using ADIsimPLL for
a channel spacing of 8 MHz and an open-loop bandwidth of
40 kHz. The maximum PFD frequency of the ADF4360-4 is
8 MHz. Because using a larger PFD frequency allows users to
use a smaller N, the in-band phase noise is reduced to as low as
possible, –100 dBc/Hz. The 40 kHz bandwidth is chosen to be
just greater than the point at which the open-loop phase noise
of the VCO is –100 dBc/Hz, thus giving the best possible integrated noise. The typical rms phase noise (100 Hz to 100 kHz)
of the LO in this configuration is 0.3°. The reference frequency
is from a 16 MHz TCXO from Fox; thus, an R value of 2 is programmed. Taking into account the high PFD frequency and its
effect on the band select logic, the band select clock divider is
enabled. In this case, a value of 8 is chosen. A very simple pullup resistor and dc blocking capacitor complete the RF output
stage.
LOCK
V
DETECT
VDD
2023221
V
7
TUNE
24
CP
A
4
RF
OUT
5
B
RF
OUT
4.7nF
V
VCO
51Ω
22.0nF
430Ω
51Ω
100pF
100pF
FOX
801BE-160
16MHz
SPI COMPATIBLE SERIAL BUS
1nF
10µF
V
VCO
6
DVDDAVDDCE MUXOUT
V
VCO
14
C
N
1nF1nF
16
REF
IN
51Ω
17
CLK
18
DATA
19
LE
12
C
C
13
R
4.7kΩ
SET
CPGND AGND DGND
1 3 8 9 10 11 22 15
Figure 18. Fixed Frequency LO
ADF4360-4
INTERFACING
The ADF4360 family has a simple SPI®-compatible serial interface for writing to the device. CLK, DATA, and LE control the
data transfer. When LE goes high, the 24 bits that have been
clocked into the appropriate register on each rising edge of CLK
are transferred to the appropriate latch. See Figure 2 for the
timing diagram and Table 5 for the latch truth table.
04438-022
ADuC812 Interface
Figure 19 shows the interface between the ADF4360 family and
the ADuC812 MicroConverter®. Because the ADuC812 is based
on an 8051 core, this interface can be used with any 8051-based
microcontroller. The MicroConverter is set up for SPI master
mode with CPHA = 0. To initiate the operation, the I/O port
driving LE is brought low. Each latch of the ADF4360 family
needs a 24-bit word, which is accomplished by writing three
8-bit bytes from the MicroConverter to the device. When the
third byte is written, the LE input should be brought high to
complete the transfer.
SCLOCK
MOSI
ADuC812
I/O PORTS
Figure 19. ADuC812 to ADF4360-x Interface
SCLK
SDATA
LE
ADF4360-x
CE
MUXOUT
(LOCK DETECT)
04438-023
I/O port lines on the ADuC812 are also used to control powerdown (CE input) and detect lock (MUXOUT configured as lock
detect and polled by the port input). When operating in the
described mode, the maximum SCLOCK rate of the ADuC812
is 4 MHz. This means that the maximum rate at which the output frequency can be changed is 166 kHz.
ADSP-21xx Interface
Figure 20 shows the interface between the ADF4360 family and
the ADSP-21xx digital signal processor. The ADF4360 family
needs a 24-bit serial word for each latch write. The easiest way
to accomplish this using the ADSP-21xx family is to use the
autobuffered transmit mode of operation with alternate framing. This provides a means for transmitting an entire block of
serial data before an interrupt is generated.
SCLOCK
MOSI
TFS
ADSP-21xx
I/O PORTS
SCLK
SDATA
LE
ADF4360-x
CE
MUXOUT
(LOCK DETECT)
The maximum allowable serial clock rate is 20 MHz. This
means that the maximum update rate possible is 833 kHz or
one update every 1.2 µs. This is certainly more than adequate
for systems that have typical lock times in hundreds of microseconds.
Set up the word length for 8 bits and use three memory locations for each 24-bit word. To program each 24-bit latch, store
the 8-bit bytes, enable the autobuffered mode, and write to the
transmit register of the DSP. This last operation initiates the
autobuffer transfer.
Rev. A | Page 21 of 24
Figure 20. ADSP-21xx to ADF4360-x Interface
04438-024
ADF4360-4
PCB DESIGN GUIDELINES FOR CHIP SCALE PACKAGE
The leads on the chip scale package (CP-24) are rectangular.
The printed circuit board pad for these should be 0.1 mm
longer than the package lead length and 0.05 mm wider than
the package lead width. The lead should be centered on the pad
to ensure that the solder joint size is maximized.
The bottom of the chip scale package has a central thermal pad.
The thermal pad on the printed circuit board should be at least
as large as this exposed pad. On the printed circuit board, there
should be a clearance of at least 0.25 mm between the thermal
pad and the inner edges of the pad pattern to ensure that shorting is avoided.
Thermal vias may be used on the printed circuit board thermal
pad to improve thermal performance of the package. If vias are
used, they should be incorporated in the thermal pad at a
1.2 mm pitch grid. The via diameter should be between 0.3 mm
and 0.33 mm, and the via barrel should be plated with 1 ounce
of copper to plug the via.
Experiments have shown that the circuit shown in Figure 22
provides an excellent match to 50 Ω over the operating
range of the ADF4360-4. This gives approximately −2 dBm
output power across the frequency range of the ADF4360-4.
Both single-ended architectures can be examined using the
EVAL-ADF4360-4EB1 evaluation board.
V
VCO
47nH
5.1nH
RF
OUT
Figure 22. Optimum ADF4360-4 Output Stage
1.8pF
50Ω
04438-026
If the user does not need the differential outputs available on
the ADF4360-4, the user may either terminate the unused output or combine both outputs using a balun. The circuit in
Figure 23 shows how best to combine the outputs.
V
VCO
The user should connect the printed circuit thermal pad to
AGND. This is internally connected to AGND.
OUTPUT MATCHING
There are a number of ways to match the output of the
ADF4360-4 for optimum operation; the most basic is to use a
50 Ω resistor to V
nected in series, as shown Figure 21. Because the resistor is not
frequency dependent, this provides a good broadband match.
The output power in this circuit typically gives −4 dBm output
power into a 50 Ω load.
A better solution is to use a shunt inductor (acting as an RF
choke) to V
VCO
output power. Additionally, a series inductor is added after the
dc bypass capacitor to provide a resonant LC circuit. This tunes
the oscillator output and provides approximately 10 dB additional rejection of the second harmonic. The shunt inductor
needs to be a relatively high value (>40 nH).
. A dc bypass capacitor of 100 pF is con-
VCO
V
VCO
51Ω
RF
OUT
Figure 21. Simple ADF4360-4 Output Stage
100pF
50Ω
04438-025
. This gives a better match and, therefore, more
4.3nH
A
RF
OUT
OUT
4.3nH
B
RF
Figure 23. Balun for Combining ADF4360-4 RF Outputs
5.1nH
1.8pF
5.1nH
1.8pF
47nH
10pF
50Ω
04438-027
The circuit in Figure 23 is a lumped-lattice-type LC balun. It is
designed for a center frequency of 1.6 GHz and outputs 4.0 dBm
at this frequency. The series 4.3 nH inductor is used to tune out
any parasitic capacitance due to the board layout from each
input, and the remainder of the circuit is used to shift the
output of one RF input by +90° and the second by −90°, thus
combining the two. The action of the 5.1 nH inductor and the
1.8 pF capacitor accomplishes this. The 47 nH is used to provide
an RF choke to feed the supply voltage, and the 10 pF capacitor
provides the necessary dc block. To ensure good RF performance, the circuits in Figure 22 and Figure 23 are implemented
with Coilcraft 0402/0603 inductors and AVX 0402 thin-film
capacitors.
Alternatively, instead of the LC balun shown in Figure 23, both
outputs may be combined using a 180° rat-race coupler.
Rev. A | Page 22 of 24
ADF4360-4
OUTLINE DIMENSIONS
0.60 MAX
19
18
EXPOSED
(BOTTOMVIEW)
13
12
PA D
24
6
7
2.50 REF
1
PIN 1
INDICATOR
*
2.45
2.30 SQ
2.15
0.23 MIN
PIN 1
INDICATOR
1.00
0.85
0.80
SEATING
PLANE
12° MAX
4.00
BSC SQ
TOP
VIEW
0.80 MAX
0.65 TYP
*
COMPLIANT TO JEDEC STANDARDS MO-220-VGGD-2
EXCEPT FOR EXPOSED PAD DIMENSION
0.30
0.23
0.18
3.75
BSC SQ
0.20 REF
0.60 MAX
0.05 MAX
0.02 NOM
COPLANARITY
BSC
0.08
0.50
0.50
0.40
0.30
Figure 24. 24-Lead Lead Frame Chip-Scale Package [VQ_LFCSP]
4 mm × 4 mm Body, Very Thin Quad (CP-24-2)
Dimensions shown in millimeters
ORDERING GUIDE
Model Temperature Range Frequency Range Package Option
ADF4360-4BCP −40°C to +85°C 1450 MHz to 1750 MHz CP-24-2
ADF4360-4BCPRL −40°C to +85°C 1450 MHz to 1750 MHz CP-24-2
ADF4360-4BCPRL7 −40°C to +85°C 1450 MHz to 1750 MHz CP-24-2
ADF4360-4BCPZ
ADF4360-4BCPZRL1 −40°C to +85°C 1450 MHz to 1750 MHz CP-24-2
ADF4360-4BCPZRL71 −40°C to +85°C 1450 MHz to 1750 MHz CP-24-2
EVAL-ADF4360-4EB1 Evaluation Board
1
Z = Pb-free model.
1
−40°C to +85°C 1450 MHz to 1750 MHz CP-24-2
Rev. A | Page 23 of 24
ADF4360-4
NOTES
Purchase of licensed I2C components of Analog Devices or one of its sublicensed Associated Companies conveys a license for the purchaser under the Philips I2C Patent
Rights to use these components in an I
2
C system, provided that the system conforms to the I2C Standard Specification as defined by Philips.
© 2004 Analog Devices, Inc. All rights reserved. Trademarks and
registered trademarks are the property of their respective owners.
C04438–0–12/04(A)
Rev. A | Page 24 of 24
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