AD ADL5390 Rf/if vector multiplier Datasheet

RF/IF Vector Multiplier
ADL5390
FEATURES
APPLICATIONS
FUNCTIONAL BLOCK DIAGRAM
VPRF
QBBP OBBM
VPS2
INMQ
INPQ
RFOP
CMRF
RFOM
INPI
INMI
CMOP
IBBP IBBM
DSOP
04954-001
Matched pair of multiplying VGAs
Broad frequency range 20 MHz to 2.4 GHz
Continuous magnitude control from +5 dB to −30 dB
Output third-order intercept 24 dBm
Output 1 dB compression point 11 dBm
Output noise floor −148 dBm/Hz
Adjustable modulation bandwidth up to 230 MHz
Fast output power disable
Single-supply voltage 4.75 V to 5.25 V
Figure 1.
PA linearization and predistortion
Amplitude and phase modulation
Variable matched attenuator and/or phase shifter
Cellular base stations
Radio links
Fixed wireless access
Broadband/CATV
RF/IF analog multiplexer
GENERAL DESCRIPTION
The ADL5390 vector multiplier consists of a matched pair of
broadband variable gain amplifiers whose outputs are summed.
The separate gain controls for each amplifier are linear-inmagnitude. If the two input RF signals are in quadrature, the
vector multiplier can be configured as a vector modulator or as
a variable attenuator/phase shifter by using the gain control pins
as Cartesian variables. In this case, the output amplitude can be
controlled from a maximum of +5 dB to less than –30 dB, and
the phase can be shifted continuously over the entire 360°
range. Since the signal paths are linear, the original modulation
on the inputs is preserved. If the two signals are independent,
then the vector multiplier can function as a 2:1 multiplexer or
can provide fading from one channel to another.
The ADL5390 operates over a wide frequency range of 20 MHz
to 2400 MHz. For a maximum gain setting on one channel at
380 MHz, the ADL5390 delivers an OP1dB of 11 dBm, an OIP3
of 24 dBm, and an output noise floor of −148 dBm/Hz. The gain
and phase matching between the two VGAs is better than 0.5 dB
and 1°, respectively, over most of the operating range.
The gain control inputs are dc-coupled with a +/−500 mV differential full-scale range centered about a 500 mV common
mode. The maximum modulation bandwidth is 230 MHz,
which can be reduced by adding external capacitors to limit the
noise bandwidth on the control lines.
Both the RF inputs and outputs can be used differentially or
single-ended and must be ac-coupled. The impedance of each
VGA RF input is 250 Ω to ground, and the differential output
impedance is nominally 50 Ω over the operating frequency
range. The DSOP pin allows the output stage to be disabled
quickly to protect subsequent stages from overdrive. The
ADL5390 operates off supply voltages from 4.75 V to 5.25 V
while consuming 135 mA.
The ADL5390 is fabricated on Analog Devices’ proprietary,
high performance 25 GHz SOI complementary bipolar IC
process. It is available in a 24-lead, Pb-free CSP package and
operates over a −40°C to +85°C temperature range. Evaluation
boards are available.
Rev. 0
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.
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.
ADL5390
TABLE OF CONTENTS
Specifications..................................................................................... 3
RF Output and Matching .......................................................... 13
Absolute Maximum Ratings............................................................ 5
Driving the I-Q Baseband Gain Controls ............................... 13
ESD Caution.................................................................................. 5
Interfacing to High Speed DACs.............................................. 14
Pin Configuration and Function Descriptions............................. 6
Generalized Modulator ............................................................. 15
Typical Performance Characteristics ............................................. 7
Vector Modulator ....................................................................... 15
General Structure ........................................................................... 11
Vector Modulator Example—CDMA2000 ............................. 15
Theory of Operation .................................................................. 11
Quadrature Modulator .............................................................. 17
Noise and Distortion.................................................................. 11
RF Multiplexer ............................................................................ 18
Applications..................................................................................... 12
Evaluation Board ............................................................................ 19
Using the ADL5390.................................................................... 12
Outline Dimensions ....................................................................... 23
RF Input and Matching.............................................................. 12
Ordering Guide .......................................................................... 23
REVISION HISTORY
10/04—Revision 0: Initial Version
Rev. 0 | Page 2 of 24
ADL5390
SPECIFICATIONS
VS = 5 V, TA = 25°C, ZO = 50 Ω, FRF = 380 MHz, single-ended source drive to INPI and INPQ, and INMI and INMQ are ac-coupled to
common, unless otherwise noted. 66.5 Ω termination resistors before ac-coupling capacitors on INPI and INPQ. The specifications refer
to one active channel with the other channel input terminated in 50 Ω. The common-mode level for the gain control inputs is 0.5 V. A
maximum gain setpoint of 1.0 refers to a differential gain control voltage of 0.5 V.
Table 1.
Parameter
OVERALL FUNCTION
Frequency Range
Gain Control Range
GAIN CONTROL INTERFACE (I and Q)
Gain Scaling
Modulation Bandwidth
Second Harmonic Distortion
Third Harmonic Distortion
Step Response
FRF = 70 MHz
Maximum Gain
Gain Conformance
Output Noise Floor
Output IP3
Output 1 dB Compression Point
Input 1 dB Compression Point
Gain Flatness
Gain Matching
Phase Matching
Input Impedance
Output Return Loss
FRF = 140 MHz
Maximum Gain
Gain Conformance
Output Noise Floor
Output IP3
Output 1 dB Compression Point
Input 1 dB Compression Point
Gain Flatness
Gain Matching
Phase Matching
Input Impedance
Output Return Loss
FRF = 380 MHz
Maximum Gain
Gain Conformance
Conditions
Min
Typ
Max
Unit
2400
35
MHz
dB
3.5
230
1/V
MHz
45
dBc
55
dBc
45
47
ns
ns
Maximum gain setpoint
Over gain setpoint of 0.2 to 1.0
Maximum gain setpoint, no RF input
RF PIN = −5 dBm, frequency offset = 20 MHz
FRF1 = 70 MHz, FRF2 = 72.5 MHz, maximum gain
setpoint
Maximum gain setpoint
Gain setpoint = 0.1
Over any 60 MHz bandwidth
At maximum gain setpoint
At maximum gain setpoint
INPI, INMI, INMQ, INMP (Pins 20, 21, 22, 23)
RFOP, RFOM (Pins 9, 10) measured through
balun
4.6
0.25
−149
−146
23
dB
dB
dBm/Hz
dBm/Hz
dBm
10.7
6.7
0.25
0.5
±0.25
250||1
9.7
dBm
dBm
dB
dB
Degrees
Ohms||pF
dB
Maximum gain setpoint
Over gain setpoint of 0.2 to 1.0
Maximum gain setpoint, no RF input
RF PIN = −5 dBm, frequency offset = 20 MHz
FRF1 = 140 MHz, FRF2 = 142.5 MHz, maximum
gain setpoint
Maximum gain setpoint
Gain setpoint = 0.1
Over any 60 MHz bandwidth
At maximum gain setpoint
At maximum gain setpoint
INPI, INMI, INMQ, INMP (Pins 20, 21, 22, 23)
RFOP, RFOM (Pins 9, 10) measured through
balun
4.5
0.25
−144
−145
24.4
dB
dB
dBm/Hz
dBm/Hz
dBm
11
7.1
0.25
0.5
±0.25
250||1
9.6
dBm
dBm
dB
dB
Degrees
Ohms||pF
dB
Maximum gain setpoint
Over gain setpoint of 0.2 to 1.0
4.1
0.25
dB
dB
20
Relative to maximum gain
QBBP, QBBM, IBBM, IBBP (Pins 4, 5, 14, 15)
500 mV p-p, sinusoidal baseband input singleended
500 mV p-p, 1 MHz, sinusoidal baseband input
differential
500 mV p-p, 1 MHz, sinusoidal baseband input
differential
For gain from −15 dB to +5 dB
For gain from +5 dB to −15 dB
Rev. 0 | Page 3 of 24
ADL5390
Parameter
Output Noise Floor
Output IP3
Output 1 dB Compression Point
Input 1 dB Compression Point
Gain Flatness
Gain Matching
Phase Matching
Input Impedance
Output Return Loss
FRF = 900 MHz
Maximum Gain
Gain Conformance
Output Noise Floor
Output IP3
Output 1 dB Compression Point
Input 1 dB Compression Point
Gain Flatness
Gain Matching
Phase Matching
Input Impedance
Output Return Loss
FRF = 2400 MHz
Maximum Gain
Gain Conformance
Output Noise Floor
Output IP3
Output 1 dB Compression Point
Input 1 dB Compression Point
Gain Flatness
Gain Matching
Phase Matching
Input Impedance
Output Return Loss
POWER SUPPLY
Positive Supply Voltage
Total Supply Current
OUTPUT DISABLE
Disable Threshold
Maximum Attenuation
Enable Response Time
Disable Response Time
Conditions
Maximum gain setpoint, no RF input
RF PIN = −5 dBm, frequency offset = 20 MHz
FRF1 = 380 MHz, FRF2 = 382.5 MHz, maximum
gain setpoint
Maximum gain setpoint
Gain setpoint = 0.1
Over any 60 MHz bandwidth
At maximum gain setpoint
At maximum gain setpoint
INPI, INMI, INMQ, INMP (Pins 20, 21, 22, 23)
RFOP, RFOM (Pins 9, 10) measured through
balun
Min
Typ
−147.5
−146
24.2
Max
Unit
dBm/Hz
dBm/Hz
dBm
11.3
8.3
0.25
0.5
±0.5
200||1
8.5
dBm
dBm
dB
dB
Degrees
Ohms||pF
dB
Maximum gain setpoint
Over gain setpoint of 0.2 to 1.0
Maximum gain setpoint, no RF input
RF PIN = −5 dBm, frequency offset = 20 MHz
FRF1 = 900 MHz, FRF2 = 902.5 MHz, maximum
gain setpoint
Maximum gain setpoint
Gain setpoint = 0.1
Over any 60 MHz bandwidth
At maximum gain setpoint
At maximum gain setpoint
INPI, INMI, INMQ, INMP (Pins 20, 21, 22, 23)
RFOP, RFOM (Pins 9, 10) measured through
balun
4.5
0.4
−149.5
−148
23.3
dB
dB
dBm/Hz
dBm/Hz
dBm
11.5
8.5
0.25
0.6
±1
180||0.6
6.8
dBm
dBm
dB
dB
Degrees
Ohms||pF
dB
Maximum gain setpoint
Over gain setpoint of 0.2 to 1.0
Maximum gain setpoint, no RF input
RF PIN = −5 dBm, frequency offset = 20 MHz
FRF1 = 2400 MHz, FRF2 = 2402.5 MHz, maximum
gain setpoint
Maximum gain setpoint
Gain setpoint = 0.1
Over any 60 MHz bandwidth
At maximum gain setpoint
At maximum gain setpoint
INPI, INMI, INMQ, INMP (Pins 20, 21, 22, 23)
RFOP, RFOM (Pins 9, 10) measured through
balun
VPRF, VPS2 (Pin 1, 18, 6); RFOP, RFOM (Pins 9, 10)
7.0
0.5
−147
−144
18.7
dB
dB
dBm/Hz
dBm/Hz
dBm
9.6
4.3
0.25
0.8
±2.5
140||0.5
13.5
dBm
dBm
dB
dB
Degrees
Ohms||pF
dB
4.75
Includes load current
DSOP (Pin 13)
DSOP = 5 V
Delay following high-to-low transition until
device meets full specifications
Delay following low-to-high transition until
device produces full attenuation
Rev. 0 | Page 4 of 24
5
135
5.25
V
mA
2.5
40
15
V
dB
ns
10
ns
ADL5390
ABSOLUTE MAXIMUM RATINGS
Table 2.
Parameters
Supply Voltage VPRF, VPS2
DSOP
IBBP, IBBM, QBBP, QBBM
RFOP, RFOM
RF Input Power at Maximum Gain
(INPI or INPQ, Single-Ended Drive)
Equivalent Voltage
Internal Power Dissipation
θJA (With Pad Soldered to Board)
Maximum Junction Temperature
Operating Temperature Range
Storage Temperature Range
Rating
5.5 V
5.5 V
2.5 V
5.5 V
10 dBm for 50 Ω
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 section of this specification is not implied. Exposure to absolute
maximum rating conditions for extended periods may affect
device reliability.
2.0 V p-p
825 mW
59°C/W
125°C
−40°C to +85°C
−65°C to +150°C
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. 0 | Page 5 of 24
ADL5390
CMRF
INPQ
INMQ
INMI
INPI
CMRF
PIN CONFIGURATION AND FUNCTION DESCRIPTIONS
24
23
22
21
20
19
VPRF 1
18 VPRF
QFLP 2
16 IFLM
TOP VIEW
(Not to Scale)
QBBP 4
15 IBBP
QBBM 5
14 IBBM
VPS2 6
8
9
10
11
12
RFOP
RFOM
CMOP
CMOP
CMOP
7
CMOP
13 DSOP
04954-002
QFLM
17 IFLP
ADL5390
3
Figure 2. LFCSP Pin Configuration
Table 3. Pin Function Descriptions
Pin No.
2, 3
Mnemonic
QFLP, QFLM
4, 5
6, 1, 18
7, 8, 11, 12,
19, 24
9, 10
13
14, 15
16, 17
QBBP, QBBM
VPS2, VPRF
CMOP, CMRF
RFOP, RFOM
DSOP
IBBM, IBBP
IFLM, IFLP
20, 21
INPI, INMI
22, 23
INMQ, INPQ
Exposed
Paddle
GND
Description
Q Baseband Input Filter Pins. Connect optional capacitor to reduce Q baseband gain control channel lowpass corner frequency.
Q Channel Differential Baseband Gain Control Inputs. Typical common-mode bias level of 0.5 V.
Positive Supply Voltage. VP of 4.75 V to 5.25 V.
Device Common. Connect via lowest possible impedance to external circuit common.
Differential RF Outputs. Must be ac-coupled. Differential impedance 50 Ω nominal.
Output Disable. Pull high to disable output stage. Connect to common for normal operation.
I Channel Differential Baseband Gain Control Inputs. Typical common-mode bias level of 0.5 V.
I Baseband Input Filter Pins. Connect optional capacitor to reduce I baseband gain control channel lowpass corner frequency.
I Channel Differential RF Inputs. Must be ac-coupled. 250 Ω impedance to common on each pin. These
inputs can be driven single-ended without any performance degradation.
Q Channel Differential RF Inputs. Must be ac-coupled. 250 Ω impedance to common on each pin. These
inputs can be driven single-ended without any performance degradation.
The exposed paddle on the underside of the package should be soldered to a low thermal and electrical
impedance ground plane.
Rev. 0 | Page 6 of 24
ADL5390
TYPICAL PERFORMANCE CHARACTERISTICS
10
5
4
CHANNEL GAIN MATCH (dB)
5
0
FRF = 70MHz
FRF = 140MHz
FRF = 380MHz
FRF = 900MHz
FRF = 2400MHz
GAIN (dB)
–5
–10
–15
–20
3
2
+3σ
1
0
–1
–3σ
–2
04954-003
–30
0
0.25
0.50
GAIN SETPOINT
0.75
04954-006
–3
–25
–4
–5
1.00
0
300
600
900
1200
1500
FREQUENCY (MHz)
1800
2100
2400
Figure 6. Channel Gain Matching (I to Q) vs. RF Frequency,
Gain Setpoint = 1.0
Figure 3. Gain Magnitude vs. Gain Setpoint, RF Frequency = 70 MHz,
140 MHz, 380 MHz, 900 MHz, 2400 MHz (Channel I or Channel Q)
9
10
TEMP = –40°C
TEMP = +25°C
TEMP = +85°C
5
TEMP = –40°C
8
TEMP = +25°C
7
0
GAIN (dB)
–10
–15
4
TEMP = +85°C
–25
1
04954-004
2
0
0.1
0.2
0.3
0.4
0.5
0.6
GAIN SETPOINT
0.7
0.8
0.9
0
1.0
Figure 4. Gain Magnitude vs. Gain Setpoint, Temp = +85°C, +25°C, −40°C,
RF Frequency = 380 MHz (Channel I or Channel Q)
04954-007
3
–20
–30
0
5
+3σ = DASH LINE
–3σ = SOLID LINE
FRF = 70MHz
FRF = 140MHz
FRF = 380MHz
FRF = 900MHz
FRF = 2400MHz
2
1
600
900
1200
1500
FREQUENCY (MHz)
0
–1
–2
04954-005
–4
0
0.25
0.50
GAIN SETPOINT
0.75
2100
2400
+3σ = DASH LINE
–3σ = SOLID LINE
–5
–10
FRF = 70MHz
FRF = 140MHz
FRF = 380MHz
FRF = 900MHz
FRF = 2400MHz
–15
–3
1800
0
PHASE ERROR (Degrees)
3
300
Figure 7. Channel Gain vs. RF Frequency, Temp = +85°C, +25°C, −40°C,
Gain Setpoint = 1.0
4
GAIN ERROR (dB)
5
–20
1.0
Figure 5. Gain Conformance Error vs. Gain Setpoint, RF Frequency = 70 MHz,
140 MHz, 380 MHz, 900 MHz, 2400 MHz
0
0.25
0.50
GAIN SETPOINT
0.75
04954-008
GAIN (dB)
6
–5
1.0
Figure 8. Single-Channel Phase Deviation vs. Gain Setpoint, Normalized to
Gain Setpoint = 1.0, RF Frequency = 70 MHz, 140 MHz, 380 MHz,
900 MHz, 2400 MHz
Rev. 0 | Page 7 of 24
ADL5390
–142
25
+3σ = DASH LINE
–3σ = SOLID LINE
15
–144
–145
NOISE (dBm/Hz)
10
–143
5
0
–5
0.2
0.4
0.6
GAIN SETPOINT
0.8
–152
1.0
04954-012
04954-009
0
NO CARRIER
PIN = –15dBm
–151
Figure 9. Channel-to-Channel Phase Matching vs. Gain Setpoint,
RF Frequency = 70 MHz, 140 MHz, 380 MHz, 900 MHz, 2400 MHz
0
0.1
0.2
0.3
0.4
0.5
0.6
GAIN SETPOINT
0.7
0.8
0.9
1.0
Figure 12. Output Noise Floor vs. Gain Setpoint, No Carrier, with Carrier
(20 MHz Offset), RF PIN = −5, −10, −15, No Carrier, RF Frequency = 380 MHz
10
–142
+3σ = DASH LINE
–3σ = SOLID LINE
TEMP = –40°C
TEMP = +25°C
TEMP = +85°C
8
6
–143
–144
4
0
–2
–146
–147
–148
–4
–149
–6
–150
–8
–10
0
600
1200
FREQUENCY (MHz)
1800
–151
–152
2400
Figure 10. Channel-to-Channel Phase Matching vs. RF Frequency, Temp =
+85°C, +25°C, −40°C, Gain Setpoint = 1.0
0
400
800
1200
1600
FREQUENCY (MHz)
2000
2400
Figure 13. Output Noise Floor vs. RF Frequency, Gain Setpoint = 1.0,
No RF Carrier
10
–142
FRF = 70MHz
FRF = 140MHz
FRF = 380MHz
FRF = 900MHz
FRF = 2400MHz
–143
–144
–145
GAIN SETPOINT = 1.0
5
GAIN SETPOINT = 0.5
0
GAIN (dB)
–146
–147
–148
–5
–10
–149
GAIN SETPOINT = 0.1
–150
04954-011
–15
–151
–152
GAIN SETPOINT = 1.0
04954-013
NOISE (dBm/Hz)
–145
2
04954-010
PHASE DIFFERENCE (Degrees)
–148
–150
–15
NOISE (dBm/Hz)
PIN = –10dBm
–147
–149
–10
–20
PIN = –5dBm
–146
0
0.1
0.2
0.3
0.4
0.5
0.6
GAIN SETPOINT
0.7
0.8
0.9
–20
1.0
04954-014
PHASE DIFFERRENCE (Degrees)
20
FRF = 70MHz
FRF = 140MHz
FRF = 380MHz
FRF = 900MHz
FRF = 2400MHz
0
400
800
1200
1600
FREQUENCY (MHz)
2000
2400
Figure 14. Gain vs. RF Frequency, Gain Setpoint = 1.0, 0.5, 0.1
Figure 11. Output Noise Floor vs. Gain Setpoint, No RF Carrier,
RF Frequency = 70 MHz, 140 MHz, 380 MHz, 900 MHz, 2400 MHz
Rev. 0 | Page 8 of 24
ADL5390
0
FUNDAMENTAL
–10
–5
1V p-p BASEBAND INPUT
SIDEBAND POWER (dBm)
–20
–40
–50
2ND HARMONIC
–60
–70
–80
–15
–20
500mV p-p BASEBAND INPUT
–25
3RD HARMONIC
–90
–100
–10
0
100
200 300 400 500 600 700 800
DIFF. BASEBAND INPUT LEVEL (mV p-p)
900
–35
1000
Figure 15. Baseband Harmonic Distortion, (Channel I and Channel Q),
RF PIN = −5 dBm, (Balun and Cable Losses Not Included)
12
250mV p-p BASEBAND INPUT
–30
0
50
100
150
200
250
BB FREQUENCY (MHz)
04954-018
–30
04954-015
RF OUTPUT SIDEBAND POWER (dBm)
0
300
350
400
Figure 18. IQ Modulation Bandwidth vs. Baseband Magnitude
15
TEMP = –40°C
TEMP = +25°C
10
11
5
OP1dB (dBm)
OP1dB (dBm)
10
TEMP = +85°C
9
FRF = 70MHz
FRF = 140MHz
FRF = 380MHz
FRF = 900MHz
FRF = 2400MHz
0
–5
–10
8
–15
7
0
400
800
1200
1600
FREQUENCY (MHz)
2000
04954-019
04954-016
6
–20
–25
0
2400
0.1
0.2
0.3
0.4
0.5
0.6
GAIN SETPOINT
0.7
0.8
0.9
1.0
Figure 19. Output 1 dB Compression vs. Gain Setpoint, RF Frequency =
70 MHz, 140 MHz, 380 MHz, 900 MHz, 2400 MHz
Figure 16. Output 1 dB Compression Point vs. RF Frequency,
Temp = +85°C, +25°C, −40°C, Gain Setpoint = 1.0
30
30
28
25
TEMP = –40°C
26
20
24
15
OIP3 (dBm)
20
TEMP = +85°C
18
5
0
16
–5
04954-017
14
12
10
FRF = 70MHz
FRF = 140MHz
FRF = 380MHz
FRF = 900MHz
FRF = 2400MHz
10
0
400
800
1200
1600
FREQUENCY (MHz)
2000
–10
–15
2400
Figure 17. Output IP3 vs. RF Frequency, Temp = +85°C, +25°C, −40°C,
Gain Setpoint = 1.0
04954-020
OIP3 (dBm)
TEMP = +25°C
22
0
0.1
0.2
0.3
0.4
0.5
0.6
GAIN SETPOINT
0.7
0.8
0.9
1.0
Figure 20. Output IP3 vs. Gain Setpoint, RF Frequency = 70 MHz, 140 MHz,
380 MHz, 900 MHz, 2400 MHz
Rev. 0 | Page 9 of 24
ADL5390
1.25
300
0
1.00
SHUNT CAPACITANCE (pF)
200
0.75
SHUNT RESISTANCE (Ω)
0.50
150
0.25
100
–10
RF OUTPUT POWER (dBm)
250
INPUT SHUNT CAPACITANCE (pF)
INPUT SHUNT RESISTANCE (Ω)
–5
–15
–20
–25
–30
–35
–40
–45
–50
–55
–60
04954-024
–65
220 420 620 820 1020 1220 1420 1620 1820 2020 2220
FRF (MHz)
04954-021
–70
50
20
0
–75
0.5
1.0
1.5
2.0
2.5
3.0
3.5
DSOP VOLTAGE (V)
4.0
4.5
5.0
Figure 24. Power Shutdown Attenuation, RF = 380 MHz
Figure 21. S11 of RF Input (Shunt R/C Representation)
TEK RUN
1
ADL5390 SDD22
90
ENVELOPE
12 AUG 04 16:48:01
60
120
150
→
|GRIDZ|
0
30
2.7GHz
0
S 11TERMANGI
3GHz
180
0
10MHz
210
04954-025
1
330
CH1 500mV Ω
CH3 2.0V Ω DS
10MHz
240
300
04954-022
IMPEDANCE CIRCLE
SDD22 NOM WFR DUT 1
270
ARG(GRIDZ), RADS(S 11TERMANG)
S22 NOM WFR
I
Figure 22. S22 of RF Output (Differential and Single-Ended through Balun)
139
Vp = 5.25
137
Vp = 5
136
135
134
Vp = 4.75
133
04954-023
SUPPLY CURRENT (mA)
138
132
–40
–25
M 10.0ns 5.0GS/s ET 200ps/pt
A CH3 760mV
–10
5
20
35
TEMPERATURE (°C)
50
65
80
Figure 23. Supply Current vs. Temperature
Rev. 0 | Page 10 of 24
Figure 25. Power Shutdown Response Time, RF = 380 MHz
ADL5390
GENERAL STRUCTURE
I CHANNEL
BASEBAND INPUT
VIBB
THEORY OF OPERATION
VIRF,
I CHANNEL
SINGLE-ENDED
OR DIFFERENTIAL
V-I
LINEAR
ATTENUATOR
SINGLE-ENDED
OR DIFFERENTIAL
50Ω OUTPUT
I-V
VQRF,
Q CHANNEL
SINGLE-ENDED
OR DIFFERENTIAL
V-I
LINEAR
ATTENUATOR
OUTPUT
DISABLE
VQBB
Q CHANNEL
BASEBAND INPUT
Since the two independent RF/IF inputs can be combined in
arbitrary proportions, the overall function can be termed
“vector multiplication” as expressed by
04954-026
The simplified block diagram given in Figure 26 shows a
matched pair of variable gain channels whose outputs are
summed and presented to the final output. The RF/IF signals
propagate from the left to the right, while the baseband gain
controls are placed above and below. The proprietary linearresponding variable attenuators offer excellent linearity, low
noise, and greater immunity from mismatches than other
commonly used methods.
Figure 26. Simplified Architecture of the ADL5390
NOISE AND DISTORTION
where:
VIRF and VQRF are the RF/IF input vectors.
VIBB and VQBB are the baseband input scalars.
VO is the built-in normalization factor, which is designed to be
0.285 V (1/3.5 V).
The overall voltage gain, in linear terms, of the I and Q channels
is proportional to its control voltage and scaled by the normalization factor, i.e., a full-scale gain of 1.75 (5 dB) for VI (Q)BB of
500 mV. A full-scale voltage gain of 1.75 defines a gain setpoint
of 1.0.
Due to its versatile functional form and wide signal dynamic
range, the ADL5390 can form the core of a variety of useful
functions such as quadrature modulators, gain and phase adjusters, and multiplexers. At maximum gain on one channel, the
output 1 dB compression point and noise floor referenced to
50 Ω are 11 dBm and −148 dBm/Hz, respectively. The broad
frequency response of the RF/IF and gain control ports allows
the ADL5390 to be used in a variety of applications at different
frequencies. The bandwidth for the RF/IF signal path extends
from approximately 20 MHz to beyond 2.4 GHz, while the gain
controls signals allow for modulation rates greater than 200 MHz.
The signal path for a particular channel of the ADL5390 consists basically of a preamplifier followed by a variable attenuator
and then an output driver. Each subblock contributes some level
of noise and distortion to the desired signal. As the channel gain
is varied, these relative contributions change. The overall effect
is a dependence of output noise floor and output distortion
levels on the gain setpoint.
For the ADL5390, the distortion is always determined by the
preamplifier. At the highest gain setpoint, the signal capacity, as
described by the 1 dB compression point (P1dB) and the thirdorder intercept (OIP3), are at the highest levels. As the gain is
reduced, the P1dB and OIP3 are reduced in exact proportion.
At the higher gain setpoints, the output noise is dominated by
the preamplifier as well. At lower gains, the contribution from
the preamplifier is correspondingly reduced and eventually a
noise floor, set by the output driver, is reached. As Figure 27
illustrates, the overall dynamic range defined as a ratio of OIP3
to output noise floor remains constant for the higher gain
setpoints. At some gain level, the noise floor levels off and the
dynamic range degrades commensurate with the gain reduction.
Matching between the two gain channels is ensured by careful
layout and design. Since they are monolithic and arranged
symmetrically on the die, thermal and process gradients are
minimized. Typical gain and phase mismatch at maximum gain
are <0.5 dB and <0.5°.
175
DYNAMIC RANGE = OIP3 – (OUTPUT NOISE
FLOOR (NO CARRIER))
170
DYNAMIC RANGE (dB × Hz)
VOUT = VIRF × (VIBB/VO) + VQRF × (VQBB/VO)
165
160
155
150
140
04954-027
145
0
0.1
0.2
0.3
0.4
0.5
0.6
GAIN SETPOINT
0.7
0.8
0.9
Figure 27. Dynamic Range Variation with Gain Setpoint
Rev. 0 | Page 11 of 24
1.0
ADL5390
APPLICATIONS
level of the ADL5390 inputs is not affected, as shown in Figure
29. Capacitive reactance at the RF inputs can be compensated
for with series inductance. In fact, the customer evaluation
board has high impedance line traces between the shunt termination pads and the device input pins, which provides series inductance and improves the return loss at 1.9 GHz to better than
−15 dB with the shunt termination removed, as shown in Figure
28.
USING THE ADL5390
The ADL5390 is designed to operate in a 50 Ω impedance system.
Figure 29 illustrates an example where the RF/IF inputs are
driven in a single-ended fashion, while the differential RF output is converted to a single-ended output with a RF balun. The
baseband gain controls for the I and Q channels are typically
driven from differential DAC outputs. The power supplies,
VPRF and VPS2, should be bypassed appropriately with 0.1 µF
and 100 pF capacitors. Low inductance grounding of the CMOP
and CMRF common pins is essential to prevent unintentional
peaking of the gain. The exposed paddle on the underside of the
package should be soldered to a low thermal and electrical
impedance ground plane.
0
S11 MATCH WITHOUT
66.5Ω TERMINATION
–5
–10
–15
dB
RF INPUT AND MATCHING
–20
The RF/IF inputs present 250 Ω resistive terminations to
ground. In general, the input signals should be ac-coupled
through dc-blocking capacitors. The inputs may be driven differentially or single-ended, in which case the unused inputs are
connected to common via the dc-blocking capacitors. The
ADL5390’s performance is not degraded by driving these inputs
single-ended. The input impedance can be reduced by placing
external shunt termination resistors to common on the source
side of the dc-blocking capacitors so that the quiescent dc-bias
S11 MATCH WITH
TERMINATION
–25
20.0
115.2
210.4
305.6
400.8
496.0
591.2
686.4
781.6
876.8
972.0
1067.2
1162.4
1257.6
1352.8
1448.0
1543.2
1638.4
1733.6
1828.8
1924.0
2019.2
2114.4
2209.6
2304.8
2400.0
–35
04954-028
–30
FREQUENCY (MHz)
Figure 28. ADL5390 Customer Evaluation Board RF Input Return Loss.
IBBP IBBM
VP
C7
0.1µF
C8
100pF
C12
(SEE TEXT)
SW1
B
VP
RFIN_I
C1
10nF
C2
10nF
C6
10nF
L2
0Ω
RFIN_Q
IBBM
IBBP
INPI
INMI
C18
10nF
RFOM
1
5
ADL5390
IPMQ
RFOP
L4
120nH
CMOP
QBBM
QBBP
VPRF
QFLM
CMRF
QFLP
C5
10nF
DSOP
CMOP
CMOP
INPQ
R22
66.5Ω
A
C17
L3
10nF
120nH
4
3
T1
ETC1-1-13
(M/A-COM)
RFOP
CMOP
C14
0.1µF
VPS2
VP
VP
C4
0.1µF
C3
100pF
C11
(SEE TEXT)
C10
100pF
C9
0.1µF
QBBP QBBM
Figure 29. Basic Connections
Rev. 0 | Page 12 of 24
04954-029
R2
66.5Ω
IFLM
VPRF
CMRF
L1
0Ω
IFLP
R8
10kΩ
ADL5390
RF OUTPUT AND MATCHING
10
The RF/IF outputs of the ADL5390, RFOP and RFOM, are open
collectors of a transimpedance amplifier that need to be pulled
up to the positive supply, preferably with RF chokes, as shown
in Figure 30. The nominal output impedance looking into each
individual output pin is 25 Ω. Consequently, the differential
output impedance is 50 Ω.
RL2 = OPEN
8
6
GAIN (dB)
RL2 = 50Ω
4
2
RL2 = SHORT
0
VP
–2
0.1µF
RT
RFOM
±ISIG
GM
RL = 50Ω
–10
10
10pF
1:1
10pF
RF
OUTPUT
04954-030
50Ω
DIFFERENTIAL
100
1000
FREQUENCY (MHz)
10000
Figure 31. Gain of the ADL5390 Using a Single-Ended Output with Different
Dummy Loads, RL2 on the Unused Output, Gain Setpoint = 1.0
RFOP
RT
04954-043
–4
120nH
Figure 30. RF Output Interface to the ADL5390 Showing
Coupling Capacitors, Pull-Up RF Chokes, and Balun
Since the output dc levels are at the positive supply, ac-coupling
capacitors are usually needed between the ADL5390 outputs
and the next stage in the system.
A 1:1 RF broadband output balun, such as the ETC1-1-13 (M/ACOM), converts the differential output of the ADL5390 into a
single-ended signal. Note that the loss and balance of the balun
directly impact the apparent output power, noise floor, and gain/
phase errors of the ADL5390. In critical applications, narrow-band
baluns with low loss and superior balance are recommended.
If the output is taken in a single-ended fashion directly into a 50 Ω
load through a coupling capacitor, there will be an impedance
mismatch. This can be resolved with a 1:2 balun to convert the
single-ended 25 Ω output impedance to 50 Ω. If loss of signal
swing is not critical, a 25 Ω back termination in series with the
output pin can also be used. The unused output pin must still be
pulled up to the positive supply. The user may load it through a
coupling capacitor with a dummy load to preserve balance. The
mismatched gain of the ADL5390 when the output is singleended varies slightly with dummy load value, as shown in Figure
31.
The RF output signal can be disabled by raising the DSOP pin
to the positive supply. The output disable function provides
>40 dB attenuation of the input signal, even at full gain. The
interface to DSOP is high impedance and the output disable
and output enable response times are <100 ns. If the output
disable function is not needed, the DSOP should be tied to
ground.
DRIVING THE I-Q BASEBAND GAIN CONTROLS
The I and Q gain control inputs to the ADL5390 set the gain for
each channel. These inputs are differential and should normally
have a common-mode level of 0.5 V. However, when differentially driven, the common mode can vary from 250 mV to
750 mV while still allowing full gain control. Each input pair
has a nominal input swing of ±0.5 V differential around the
common-mode level. The maximum gain is achieved if the
differential voltage is equal to +500 mV or −500 mV. So with a
common-mode level of 500 mV, IBBP and IBBM will each
swing between 250 mV and 750 mV.
The I and Q gain control inputs can also be driven with a singleended signal. In this case, one side of each input should be tied
to a low noise 0.5 V voltage source (a 0.1 µF decoupling capacitor located close to the pin is recommended), while the other
input swings from 0 V to 1 V. Low speed, single-ended drive can
easily be achieved using 12-bit voltage output DACs such as
AD8303 (serial SPI® interface) or AD8582 (parallel interface)
DACs. A reference voltage should also be supplied. Differential
drive generally offers superior even-order distortion and lower
noise than single-ended drive.
The bandwidth of the baseband controls exceeds 200 MHz even
at full-scale baseband drive. This allows for very fast gain modulation of the RF input signal. In cases where lower modulation
bandwidths are acceptable or desired, external filter capacitors
can be connected across Pins IFLP to IFLM and Pins QFLP to
QFLM to reduce the ingress of baseband noise and spurious
signal into the control path.
Rev. 0 | Page 13 of 24
ADL5390
The 3 dB bandwidth is set by choosing CFLT according to the
following equation:
f 3 dB ≈
AD9777
ADL5390
IBBP
IOUTA1
45 kHz × 10 nF
R1
C external + 0.5 pF
R2
OPTIONAL
LOW-PASS
FILTER
R3
IOUTB1
IBBM
This equation has been verified for values of CFLT from 10 pF to
0.1 µF (bandwidth settings of approximately 4.5 kHz to 43 MHz).
IOUTA2
INTERFACING TO HIGH SPEED DACs
The AD977x family of dual DACs is well suited to driving the I
and Q gain controls of the ADL5390 with fast modulating signals. While these inputs can in general be driven by any DAC,
the differential outputs and bias level of the ADI TxDAC® family allows for a direct connection between DAC and modulator.
Bias Level = Average Output Current × R1
For example, if the full-scale current from each output is 20 mA,
each output will have an average current of 10 mA. Therefore,
to set the bias level to the recommended 0.5 V, R1 and R2
should be set to 50 Ω each. R1 and R2 should always be equal.
If R3 is omitted, this will result in an available swing from the
DAC of 2 V p-p differential, which is twice the maximum voltage
range required by the ADL5390. DAC resolution can be maximized by adding R3, which scales down this voltage according
to the following equation:
⎡
R2 ⎤
2 × I MAX (R1 || (R2 + R3)) × ⎢1 −
⎥
⎢⎣ R2 + R3 ⎥⎦
OPTIONAL
LOW-PASS
FILTER
R3
IOUTB2
04954-032
QBBM
Figure 32. Basic AD9777-to-ADL5390 Interface
1.15
1.13
1.10
1.08
1.05
1.02
1.00
0.97
0.95
0.92
0.90
0.88
0.85
0.82
0.80
0.77
0.75
0.72
0.70
50 55 60 65 70 75 80 85 90 95 100 105 110 115 120 125 130
R3 (Ω)
04954-033
The basic interface between the AD9777 DAC outputs and the
ADL5390 I and Q gain control inputs is shown in Figure 32.
Resistors R1 and R2 (R1 = R2) set the dc bias level according to
the following equation:
R2
DIFFERENTIAL PEAK-PEAK SWING (R3) (V p-p)
The AD977x family of dual DACs has differential current outputs. The full-scale current is user programmable and is usually
set to 20 mA, that is each output swings from 0 mA to 20 mA.
Full Scale Swing =
QBBP
R1
Figure 33. Peak-Peak DAC Output Swing vs.
Swing Scaling Resistor R3 (R1 = R2 = 50 Ω)
Figure 33 shows the relationship between the value of R3 and
the peak baseband voltage with R1 and R2 equal to 50 Ω. As
shown in Figure 33, a value of 100 Ω for R3 will provide a
peak-peak swing of 1 V p-p differential into the ADL5390’s
I and Q inputs.
When using a DAC, low-pass image reject filters are typically
used to eliminate the Nyquist images produced by the DAC.
They also provide the added benefit of eliminating broadband
noise that might feed into the modulator from the DAC.
Rev. 0 | Page 14 of 24
ADL5390
GENERALIZED MODULATOR
The ADL5390 can be configured as a traditional IQ quadrature
modulator or as a linear vector modulator by applying signals
that are in quadrature to the RF/IF input channels. Since the
quadrature generation is performed externally, its accuracy and
bandwidth are determined by the user. The user-defined bandwidth is attractive for multioctave or lower IF applications
where on-chip, high accuracy quadrature generation is traditionally difficult or impractical. The gain control pins (IBBP/M
and QBBP/M) become the in-phase (I) and quadrature (Q) baseband inputs for the quadrature modulator and the gain/phase
control for the vector modulator. The wide modulation bandwidths of the gain control interface allow for high fidelity baseband signals to be generated for the quadrature modulator and
for high speed gain and phase adjustments to be generated for
the vector modulator.
RF/IF signals can be introduce to the ADL5390 in quadrature
by using a two-way 90o power splitter such as the Mini-Circuits
QCN-12. Each output of an ideal 90o power splitter is 3 dB
smaller than the input and has a 90o phase difference from the
other output. In reality, the 90o power splitter will have its own
insertion loss, which can be different for each output, causing a
magnitude imbalance. Furthermore, quadrature output will not
be maintained over a large frequency range, introducing a phase
imbalance. The type of 90o power splitter that should be used
for a particular application will be determined by the frequency,
bandwidth, and accuracy needed. In some applications minor
magnitude and phase imbalances can be adjusted for in the
I/Q gain control inputs.
VECTOR MODULATOR
inputs VIBB and VQBB. The resultant of their vector sum represents
the vector gain, which can also be expressed as a magnitude and
phase. By applying different combinations of baseband inputs,
any vector gain within the unit circle can be programmed. The
magnitude and phase (with respect to 90o) accuracy of the 90o
power splitter will directly affect this representation and could
be seen as an offset and skew of the circle.
A change in sign of VIBB or VQBB can be viewed as a change in
sign of the gain or as a 180° phase change. The outermost circle
represents the maximum gain magnitude. The circle origin
implies, in theory, a gain of 0. In practice, circuit mismatches
and unavoidable signal feedthrough limit the minimum gain to
approximately −30 dB. The phase angle between the resultant
gain vector and the positive x-axis is defined as the phase shift.
Note that there is a nominal, systematic insertion phase through
the ADL5390 to which the phase shift is added. In the following
discussions, the systematic insertion phase is normalized to 0°.
The correspondence between the desired gain and phase and
the Cartesian inputs VIBB and VQBB is given by simple trigonometric identities
Gain =
[(V
IBB
(
/ VO )2 + VQBB / VO
)]
2
Phase = arctan(VQBB / VIBB )
where:
VO is the baseband scaling constant (285 mV).
VIBB and VQBB are the differential I and Q baseband voltages
centered around 500 mV, respectively (VIBB = VIBBP − VIBBM;
VQBB = VQBBP − VQBBM).
Vq
MAX GAIN = 5dB
Note that when evaluating the arctangent function, the proper
phase quadrant must be selected. For example, if the principal
value of the arctangent (known as arctangent(x)) is used, quadrants 2 and 3 would be interpreted mistakenly as quadrants 4
and 1, respectively. In general, both VIBB and VQBB are needed in
concert to modulate the gain and the phase.
+0.5
A
|A|
+0.5
MIN GAIN < –30dB
–0.5
Vi
04954-034
θ
–0.5
Figure 34. Vector Gain Representation
The ADL5390 can be used as a vector modulator by driving the
RF I and Q inputs single-ended through a 90o power splitter. By
controlling the relative amounts of I and Q components that are
summed, continuous magnitude and phase control of the gain
is possible. Consider the vector gain representation of the
ADL5390 expressed in polar form in Figure 34. The attenuation
factors for the RF I and Q signal components are represented on
the x-axis and y-axis, respectively, by the baseband gain control
Pure amplitude modulation is represented by radial movement
of the gain vector tip at a fixed angle, while pure phase modulation is represented by rotation of the tip around the circle at a
fixed radius. Unlike traditional I-Q modulators, the ADL5390 is
designed to have a linear RF signal path from input to output.
Traditional I-Q modulators provide a limited LO carrier path
through which any amplitude information is removed.
VECTOR MODULATOR EXAMPLE—CDMA2000
The ADL5390 can be used as a vector modulator by driving the
RF I and Q inputs (INPI and INPQ) single-ended through a 90o
power splitter and controlling the magnitude and phase using
the gain control inputs. To demonstrate operation as a vector
modulator, an 880 MHz single-carrier CDMA2000 test model
signal (forward pilot, sync, paging, and six traffic as per
Rev. 0 | Page 15 of 24
ADL5390
ACP is still in compliance with the standard (<−45 dBc @
750 kHz and <−60 dBc @ 1.98 MHz) even with output powers
greater than +3 dBm. At low output power levels, ACP at
1.98 MHz carrier offset degrades as the noise floor of the
ADL5390 becomes the dominant contributor to measured ACP.
Measured noise at 4 MHz carrier offset begins to increase
sharply above 2 dBm output power. This increase is not due to
noise, but results from increased carrier-induced distortion. As
output power drops below 2 dBm, the noise floor drops towards
−90 dBm.
3GPP2 C.S0010-B, Table 6.5.2.1) was applied to the ADL5390.
A cavity-tuned filter was used to reduce noise from the signal
source being applied to the device. The 4.6 MHz pass band of
this filter is apparent in the subsequent spectral plots.
Figure 35 shows the output signal spectrum for a programmed
gain and phase of 5 dB and 45 o. POUT is equal to 0 dBm and
VIBB = VQBB = 0.353 V (centered around 500 mV), i.e., VIBBP −
VIBBM = VQBBP − VQBBM = 0.353 V. Adjacent channel power is
measured in 30 kHz resolution bandwidth at 750 kHz and
1.98 MHz carrier offset. Noise floor is measured at ±4 MHz
carrier offset in a 1 MHz resolution bandwidth.
MARKER 1 [T1]
–14.38dBm
880.00755511MHz
RBW 30kHz
VWB 300kHz
SWT 2s
RF ATT
MIXER
UNIT
20dB
–10dBm
dB
1 [T1] –14.38dBm
880.00755511MHz
CH PWR
1 [T1]
–14.38dBm
880.00755511MHz
CH PWR
0.13dBm
ACP UP
–62.00dB
ACP LOW –61.98dB
ALT1 UP
–87.02dB
ALT1 LOW –87.04dB
–10
1
–20
–30
1AVG
A
VOUT vs. VIBB/VQBB
RF OUTPUT POWER (dBm)
EXT
–60
–70
C0
C0
Cl2
Cl2
–80
Cl1
Cl1
–100
04954-035
CU1
CU1
–90
CU2
CU2
CENTER 880MHz
500kHz/
–40
–2
1RM
–40
–50
–30
5
–50
–9
ACP: 750kHz OFFSET, 30kHz RBW
–60
–16
–70
–23
ACP: 1.98MHz OFFSET, 30kHz RBW
–80
–30
–90
–37
SPAN 5MHz
NOISE: 4MHz OFFSET, 1MHz RBW
Figure 35. Output Spectrum, Single-Carrier CDMA2000 Test Model at −5 dBm,
VI = VQ = 0.353 V, ACP Measured at 750 kHz and 1.98 MHz Carrier Offset,
Input Signal–Filtered Using a Cavity-Tuned Filter (Pass Band = 4.6 MHz)
–30
–40
–40
–50
–50
ACP (dBc)
ACP: 750kHz OFFSET, 30kHz RBW
–60
–60
–70
–70
ACP: 1.98MHz OFFSET, 30kHz RBW
–80
–80
–90
–90
NOISE: 4MHz OFFSET, 1MHz RBW
–100
–30
–100
–25
–20
–15
–10
–5
OUTPUT POWER (dBm)
0
0.1
0.2
0.3
0.4
–100
0.5
VI(Q)BB
Figure 37. Output Power, Noise, and ACP vs. I and Q Control Voltages,
CDMA2000 Test Model, VI = VQ, ACP Measured in 30 kHz RBW at ±750 MHz
and ±1.98 MHz Carrier Offset, Noise Measured at ±4 MHz Carrier Offset
In contrast to Figure 36, Figure 37 shows that for a fixed input
power, ACP remains fairly constant as gain and phase are
changed (this is not true for very high RF input powers) until
the noise floor of the ADL5390 becomes the dominant contributor to the measured ACP.
04954-044
–30
0
NOISE (dBm @ 4MHz Carrier Offset)
Holding the I and Q gain control voltages steady at 0.353 V,
input power was swept. Figure 36 shows the resulting output
power, noise floor, and adjacent channel power ratio. The noise
floor is presented as noise in a 1 MHz bandwidth as defined by
the 3GPP2 specification.
–44
NOISE (dBm @ 4MHz Carrier Offset)
ACP (dBc)
REF LVL
5dBm
0.7dB OFFSET
04954-045
0
With a fixed input power of 2.16 dBm, the output power was
again swept by changing VIBB and VQBB from 0 V to 500 mV.
The resulting output power, ACP, and noise floor are shown in
Figure 37.
5
Figure 36. Noise and ACP vs. Output Power, Single-Carrier CDMA2000 Test
Model, VI = VQ = 0.353, ACP Measured in 30 kHz RBW at ±750 kHz and
±1.98 MHz Carrier Offset, Noise Measured at ±4 MHz Carrier Offset
Rev. 0 | Page 16 of 24
ADL5390
* RBW
QUADRATURE MODULATOR
REF 7dBm
The ADL5390 can be used as a quadrature modulator by driving
the RF I and Q inputs (INPI and INPQ) single-ended through a
90o phase splitter to serve as the LO input. I/Q modulation is
applied to the baseband I and Q gain control inputs (IBBP/IBBM
and QBBP/QBBM). A simplified schematic is shown in Figure
38.
3kHz
VWB 10kHz
SWT 780ms
ATT 35dB
DESIRED SIDEBAND
0 –16.20dBm
A
900.998397436MHz
1 AP
CLRWR
–10 UNDESIRED SIDEBAND
–20
–30
–40
–50
I DATA
1
–23.27dB
–1.996794872MHz
THIRD BASEBAND HARMONIC
–37.38dB
–4.004807692MHz
2
LO FEEDTHROUGH
–41.27dB
–998.397435897kHz
3
4
–60
IBBP
SUM
PORT
10nF
PORT 1
-80
INPI
66.5Ω
04954-039
LO IN
IBBM
–70
RFOM
10nF 1
-90
5
CENTER 900MHz
QCN-12
90° PHASE
SPLITTER
4
ROFP
QBBM
66.5Ω
50Ω
3
ETC1-1-13
(M/A-COM)
INPQ
700kHz/
SPAN 7MHz
10nF
RFOP
10nF
PORT 2
QBBP
TERM
PORT
ADL5390
Figure 39. SSB Quadrature Modulator Result Using External 90° Phase Splitter,
RF PIN = −15 dBm, VIBB = VQBB = 0.5 V
(With Reference to a Common-Mode Voltage of 0.5 V)
* RBW
REF 7dBm
0 –16.78dBm
A
900.998397436MHz
1 AP
CLRWR
Figure 38. Quadrature Modulator Application
3kHz
VWB 10kHz
SWT 780ms
DESIRED SIDEBAND
04954-038
Q DATA
ATT 35dB
–10 UNDESIRED SIDEBAND
1
–51.81dB
–20 –1.996794872MHz
THIRD BASEBAND HARMONIC
–38.45dB
–30 –4.004807692MHz
LO FEEDTHROUGH
–40 –41.49dB
–998.397435897kHz
–50
3
4
–60
2
–70
–80
04954-046
Single sideband performance of a quadrature modulator is
determined by the magnitude and phase balance (compared to
a 90o offset) at the summation point of the I and Q signals.
Because the ADL5390 has matched amplifiers and mixers in
the I and Q channel, most of the single sideband performance
will be determined by the external 90o phase splitter. Good
single sideband performance can be achieved by choosing a
well-balanced 90o phase splitter. However, phase and magnitude
differences in the 90o phase splitter can be corrected by adjusting
the magnitude and phase of the I and Q data. Figure 39 shows
the performance of the ADL5390 used in conjunction with MiniCircuits QCN-12 90o power splitter. Figure 40 shows the single
sideband improvement as the I and Q data is adjusted in magnitude
and phase to achieve better single sideband performance.
–90
CENTER 900MHz
700kHz/
SPAN 7MHz
Figure 40. SSB Modulator Applications with Gain and Phase Errors Corrected,
RF Pin = −15 dBm, VIBB = VQBB = 0.5 V (With Reference to a Common-Mode
Voltage of 0.5 V), I/Q Phase Offset by 3o, and Magnitude Offset by 0.5 V
For maximum dynamic range, the ADL5390 should be driven
as close to the output 1 dB compression point as possible. The
output power of the ADL5390 increases linearly with the RF
(LO) input power and baseband gain control input voltage until
the ADL5390 reaches compression. At the 1 dB compression
point, the lower sideband starts to increase. Figure 41 demonstrates the output spectrum of a 3-carrier CDMA2000 signal
applied to the I/Q baseband gain control inputs. As the RF (LO)
power is increased, the relative amount of noise is reduced until
the ADL5390 goes into compression. At this point, the relative
noise increases, as shown in Figure 42.
Analog Devices has several quadrature/vector modulators that
have highly accurate integrated 90o phase splitters—AD8340,
AD8341, AD8345, AD8346, AD8349—that cover a variety of
frequency bands.
Rev. 0 | Page 17 of 24
ADL5390
REF –26.6dBm
–30
*ATT 5dB
*RBW 10kHz
*VBW 300kHz
*SWT 4s
RF MULTIPLEXER
POS –26.623dBm
A
–40
–50
1 RM
AVG
* –60
–70
–80
–90
NOR
–100
–110
The ADL5390 may also be used as an RF multiplexer. In this
application, two RF signals are applied to the INPI and INPQ
inputs, and the baseband voltages control which of the two RF
signals appears at the output. Figure 43 illustrates this application and shows that with VIBB = 0.5 and VQBB = 0.0 (with reference to a common-mode voltage of 0.5 V). The INPI signal is
presented to the output. Then, when VIBB transitions to VIBB =
0.0 and VQBB remains equal to zero, there is no RF output.
Lastly, as VQBB transitions to 0.5 V, the INPQ signal appears at
the output. With VIBB = 0.0 and VQBB = 0.0, the isolation to the
output is typically >40 dB at 380 MHz.
–120
TEK STOPPED
1.29MHz/
STANDARD: CDMA IS95C CLASS 0 FWD
ADJACENT CHANNEL
Tx CHANNELS
LOWER
UPPER
CH1 (REF)
CH2
CH3
–22.93dBm
–22.83dBm
–22.95dBm
TOTAL
–18.13dBm
200 Acqs
24 AUG 04 11:08:40
SPAN 12.9MHz
–59.25dB
–59.43dB
CH2
ALTERNATE CHANNEL
LOWER
UPPER
–62.79dB
–63.11dB
VIBB
04954-037
CENTER 880MHz
2ND ALTERNATE CHANNEL
LOWER
UPPER
–60.71dB
–60.32dB
Figure 41. ADL5390 as a Quadrature Modulator with the Use of an External
90° Phase Splitter, RF/LO Power = −1 dBm and Gain Control Inputs Driven
Differentially with 0.353 VP-P, 3-Carrier CDMA2000 I/Q Data
–69
2
CH3
VQBB
CH1
3
1
RF OUTPUT
04954-047
NOISE (dBc) - 8MHz OFFSET - 1MHz RBW
CH1 200mV Ω CH2 500mV Ω DS M 40.0ns 1.25GS/s 800ps/pt
CH3 500mV Ω DS
A CH2 780mV
–71
–72
Figure 43. ADL5390 in RF Multiplexer Application
–73
–74
–75
–76
–77
–78
–25
04954-031
NOISE (dBC) (1MHz RBW)
–70
–20
–15
–10
OUTPUT POWER (dBm)
–5
0
Figure 42. Noise vs. Output Power
Rev. 0 | Page 18 of 24
ADL5390
EVALUATION BOARD
The evaluation board circuit schematic for the ADL5390 is
shown in Figure 44.
The evaluation board is configured to be driven from a
single-ended 50 Ω source. Although the input of the ADL5390
is differential, it may be driven single-ended with no loss of
performance.
The low-pass corner frequency of the baseband I and Q channels can be reduced by installing capacitors in the C11 and C12
positions. The low-pass corner frequency for either channel is
approximated by
f 3 dB ≈
45 kHz × 10 nF
C external + 0.5 pF
On this evaluation board, the I and Q baseband circuits are
identical to each other, so the following description applies to
each. The connections and circuit configuration for the I/Q
baseband inputs are described in Table 4.
The baseband input of the ADL5390 requires a differential voltage drive. The evaluation board is set up to allow such a drive
by connecting the differential voltage source to QBBP and
QBBM. The common-mode voltage should be maintained at
approximately 0.5 V. For this configuration, Jumpers W1 to W4
should be removed.
The baseband input of the evaluation board may also be driven
with a single-ended voltage. In this case, a bias level is provided
to the unused input from Potentiometer R10 by installing either
W1 or W2.
Setting SW1 in Position B disables the ADL5390 output amplifier.
With SW1 set to Position A, the output amplifier is enabled. With
SW1 set to Position A, an external voltage signal, such as a pulse,
can be applied to the DSOP SMA connector to exercise the
output amplifier enable/disable function.
Rev. 0 | Page 19 of 24
ADL5390
Table 4. Evaluation Board Configuration Options
Component
R7, R9, R11, R14,
R15, R19, R20,
R21, C15, C19,
W3, W4
Function
I Channel Baseband Interface. Resistors R7 and R9 may be installed to
accommodate a baseband source that requires a specific terminating
impedance. Capacitors C15 and C19 are bypass capacitors. For single-ended
baseband drive, the Potentiometer R11 can be used to provide a bias level to
the unused input (install either W3 or W4).
R1, R3, R10, R12,
R13, R16, R17,
R18, C16, C20,
W1, W2
Q Channel Baseband Interface. See the I Channel Baseband Interface section.
C11, C12
Baseband Low-Pass Filtering. By adding capacitor C11 between QFLP and
QFLM, and capacitor C12 between IFLP and IFLM, the 3 dB low-pass corner
frequency of the baseband interface can be reduced from 230 MHz (nominal)
as given by the equation in the Evaluation Board section.
Output Interface. The 1:1 balun transformer, T1, converts the 50 Ω differential
output to 50 Ω single-ended. C17 and C18 are dc blocks. L3 and L4 provide dc
bias for the output.
I and Q Channel RF Input Interface. The single-ended impedance to the
ADL5390 RF inputs is 200 Ω. Shunt terminations R2 and R22 of 66.5 Ω bring the
impedances to 50 Ω. C2 and C5 are dc blocks. C1 and C6 are used to ac-couple
the unused side of the differential inputs to common.
T1, C17, C18, L3,
L4
C2, C1, R2
C5, C6, R22
Default Conditions
R7, R9 = not installed
R11 = potentiometer, 2 kΩ, 10 turn
(Bourns)
R14 = 4 kΩ (size 0603)
R15 = 44 kΩ (size 0603)
R19, R20, R21 = 0 Ω (size 0603)
C15, C19 = 0.1 µF
(Size 0603)
W3 = jumper (installed)
W4 = jumper (open)
R1, R3 = not installed
R10 = potentiometer, 2 kΩ, 10 turn
(Bourns)
R12 = 4 kΩ (size 0603)
R13 = 44 kΩ (size 0603)
R16, R17, R18 = 0 Ω
(size 0603)
C16, C20 = 0.1 µF (size 0603)
W1 = jumper (installed)
W2 = jumper (open)
C11, C12 = not installed
C17, C18 = 10 nF (size 0603)
T1 = ETC1-1-13 (M/A-COM)
L3, L4 = 120 nH (size 0603)
C2 = C1 = 10 nF (size 0603)
R2 = 66.5 Ω 10 (size 0603)
C5 = C6 = 10 nF (size 0603)
R22 = 66.5 Ω 10 (size 0603)
R4, R6, R5, C4, C7
C9, C3, C8, C10
Power Supply Decoupling.
R4, R6, R5 = 0 Ω (size 0603)
C4, C7 C9 = 0.1uF (size 0603)
C3, C8, C10 = 100 pF (size 0603)
R8, SW1
Output Disable Interface. The output stage of the ADL5390 is disabled by
applying a high voltage to the DSOP pin by moving SW1 to Position B. The
output stage is enabled moving SW1 to Position A. The output disable
function can also be exercised by applying an external high or low voltage to
the DSOP SMA connector with SW1 in Position A.
R8 = 10 kΩ (size 0603)
SW1 = SPDT (Position A, output
enabled)
Rev. 0 | Page 20 of 24
ADL5390
IBBP
VP
TEST POINT
IBBM
C19
R7
0.1µF (OPEN)
R9
(OPEN)
R21
0Ω
GND
TEST POINT
R19
0Ω
W3
W4
R20
0Ω
C15
0.1µF
VP
R14
4kΩ
VP
C8
100pF
R5
0Ω
R15
44kΩ
C12
(OPEN)
B
SW1
C1
10nF
C6
10nF
IBBM
CMOP
INMI
RFOM
RFOP
INPQ
CMOP
CMRF
VPRF
QBBM
C5
10nF
IPMQ
QBBP
RFIN_Q
C18
10nF
L4
120nH
1
5
C17
L3
10nF
120nH
4
3
T1
ETC1-1-13
(M/A-COM)
RFOP
CMOP
VPS2
R6
0Ω
R4
0Ω
C14
0.1µF
VP
VP
C4
0.1µF
DSOP
ADL5390
L2
0Ω
R22
66.5Ω
A
DSOP
CMOP
INPI
QFLM
C2
10nF
QFLP
R2
66.5Ω
IBBP
L1
0Ω
RFIN_I
IFLM
VPRF
CMRF
IFLP
R8
10kΩ
C3
100pF
C10
100pF
C11
(OPEN)
R12
4kΩ
R10
2kΩ
C9
0.1µF
R13
44kΩ
VP
C16
0.1µF
W2
R17
0Ω
W1
R16
0Ω
R1
(OPEN)
R18
0Ω
R3
C20 (OPEN)
0.1µF
QBBP
QBBM
Figure 44. Evaluation Board Schematic
Rev. 0 | Page 21 of 24
04954-040
C7
0.1µF
R11
2kΩ
04954-042
04954-041
ADL5390
Figure 45. Component Side Layout
Figure 46. Component Side Silkscreen
Rev. 0 | Page 22 of 24
ADL5390
OUTLINE DIMENSIONS
0.60 MAX
4.00
BSC SQ
PIN 1
INDICATOR
0.60 MAX
TOP
VIEW
0.50
BSC
3.75
BSC SQ
0.50
0.40
0.30
1.00
0.85
0.80
12° MAX
PIN 1
INDICATOR
19
18
24 1
2.45
2.30 SQ*
2.15
EXPOSED
PAD
(BOTTOMVIEW)
13
12
7
0.80 MAX
0.65 TYP
6
0.23 MIN
2.50 REF
0.05 MAX
0.02 NOM
0.30
0.23
0.18
SEATING
PLANE
0.20 REF
COPLANARITY
0.08
*COMPLIANT TO JEDEC STANDARDS MO-220-VGGD-2
EXCEPT FOR EXPOSED PAD DIMENSION
Figure 47. 24-Lead Lead Frame Chip Scale Package [LFCSP]
4 × 4 mm Body
(CP-24-2)
Dimensions shown in millimeters
ORDERING GUIDE
Models
ADL5390ACPZ-WP1, 2
ADL5390ACPZ-REEL71
ADL5390-EVAL
1
2
Temperature Range
−40°C to +85°C
−40°C to +85°C
Package Description
24-Lead Lead Frame Chip Scale Package (LFCSP)
24-Lead Lead Frame Chip Scale Package (LFCSP)
Evaluation Board
Z = Pb-free part.
WP = waffle pack.
Rev. 0 | Page 23 of 24
Package Option
CP-24-2
CP-24-2
Order Multiple
64
1,500
1
ADL5390
NOTES
© 2004 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners.
D04954–0–10/04(0)
Rev. 0 | Page 24 of 24
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