Datasheet ADL5390 Datasheet (Analog Devices)

Page 1

FEATURES

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

APPLICATIONS

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
RF/IF Vector Multiplier
ADL5390

FUNCTIONAL BLOCK DIAGRAM

VPRF
INMQ
INPQ
CMRF
INPI
INMI
CMOP
Figure 1.
VPS2OBBMQBBP
RFOP
RFOM
DSOPIBBMIBBP
04954-001

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 Anal og 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 Fax: 781.326.8703 © 2004 Analog Devices, Inc. All rights reserved.
www.analog.com
Page 2
ADL5390
TABLE OF CONTENTS
Specifications..................................................................................... 3
RF Output and Matching .......................................................... 13
Absolute Maximum Ratings............................................................ 5
ESD Caution.................................................................................. 5
Pin Configuration and Function Descriptions............................. 6
Typical Performance Characteristics............................................. 7
General Structure ........................................................................... 11
Theory of Operation ..................................................................11
Noise and Distortion.................................................................. 11
Applications..................................................................................... 12
Using the ADL5390.................................................................... 12
RF Input and Matching.............................................................. 12
REVISION HISTORY
10/04—Revision 0: Initial Version
Driving the I-Q Baseband Gain Controls............................... 13
Interfacing to High Speed DACs.............................................. 14
Generalized Modulator ............................................................. 15
Vec t or Mo d ul a t or ....................................................................... 15
Vector Modulator Example—CDMA2000 ............................. 15
Quadrature Modulator.............................................................. 17
RF Multiplexer............................................................................ 18
Evaluation Board ............................................................................ 19
Outline Dimensions ....................................................................... 23
Ordering Guide .......................................................................... 23
Rev. 0 | Page 2 of 24
Page 3
ADL5390

SPECIFICATIONS

VS = 5 V, TA = 25°C, ZO = 50 , 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 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 . 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 Conditions Min Typ Max Unit
OVERALL FUNCTION
Frequency Range Gain Control Range Relative to maximum gain 35 dB
GAIN CONTROL INTERFACE (I and Q) QBBP, QBBM, IBBM, IBBP (Pins 4, 5, 14, 15)
Gain Scaling 3.5 1/V Modulation Bandwidth
Second Harmonic Distortion
Third Harmonic Distortion
Step Response For gain from −15 dB to +5 dB 45 ns For gain from +5 dB to −15 dB 47 ns
FRF = 70 MHz
Maximum Gain Maximum gain setpoint 4.6 dB Gain Conformance Over gain setpoint of 0.2 to 1.0 0.25 dB Output Noise Floor Maximum gain setpoint, no RF input −149 dBm/Hz RF PIN = −5 dBm, frequency offset = 20 MHz −146 dBm/Hz Output IP3
Output 1 dB Compression Point Maximum gain setpoint 10.7 dBm Input 1 dB Compression Point Gain setpoint = 0.1 6.7 dBm Gain Flatness Over any 60 MHz bandwidth 0.25 dB Gain Matching At maximum gain setpoint 0.5 dB Phase Matching At maximum gain setpoint ±0.25 Degrees Input Impedance INPI, INMI, INMQ, INMP (Pins 20, 21, 22, 23)
Output Return Loss
FRF = 140 MHz
Maximum Gain Maximum gain setpoint 4.5 dB Gain Conformance Over gain setpoint of 0.2 to 1.0 0.25 dB Output Noise Floor Maximum gain setpoint, no RF input −144 dBm/Hz RF PIN = −5 dBm, frequency offset = 20 MHz −145 dBm/Hz Output IP3
Output 1 dB Compression Point Maximum gain setpoint 11 dBm Input 1 dB Compression Point Gain setpoint = 0.1 7.1 dBm Gain Flatness Over any 60 MHz bandwidth 0.25 dB Gain Matching At maximum gain setpoint 0.5 dB Phase Matching At maximum gain setpoint ±0.25 Degrees Input Impedance INPI, INMI, INMQ, INMP (Pins 20, 21, 22, 23)
Output Return Loss
FRF = 380 MHz
Maximum Gain Maximum gain setpoint 4.1 dB Gain Conformance Over gain setpoint of 0.2 to 1.0 0.25 dB
20 2400 MHz
500 mV p-p, sinusoidal baseband input single-
230 MHz
ended 500 mV p-p, 1 MHz, sinusoidal baseband input
45 dBc
differential 500 mV p-p, 1 MHz, sinusoidal baseband input
55 dBc
differential
= 70 MHz, F
F
RF1
= 72.5 MHz, maximum gain
RF2
23 dBm
setpoint
Ohms||pF
RFOP, RFOM (Pins 9, 10) measured through
250||1
9.7 dB
balun
= 140 MHz, F
F
RF1
= 142.5 MHz, maximum
RF2
24.4 dBm
gain setpoint
Ohms||pF
RFOP, RFOM (Pins 9, 10) measured through
250||1
9.6 dB
balun
Rev. 0 | Page 3 of 24
Page 4
ADL5390
Parameter Conditions Min Typ Max Unit
Output Noise Floor Maximum gain setpoint, no RF input −147.5 dBm/Hz RF PIN = −5 dBm, frequency offset = 20 MHz −146 dBm/Hz Output IP3
= 380 MHz, F
F
RF1
= 382.5 MHz, maximum
RF2
gain setpoint Output 1 dB Compression Point Maximum gain setpoint 11.3 dBm Input 1 dB Compression Point Gain setpoint = 0.1 8.3 dBm Gain Flatness Over any 60 MHz bandwidth 0.25 dB Gain Matching At maximum gain setpoint 0.5 dB Phase Matching At maximum gain setpoint ±0.5 Degrees Input Impedance INPI, INMI, INMQ, INMP (Pins 20, 21, 22, 23)
Output Return Loss
RFOP, RFOM (Pins 9, 10) measured through
balun
FRF = 900 MHz
Maximum Gain Maximum gain setpoint 4.5 dB Gain Conformance Over gain setpoint of 0.2 to 1.0 0.4 dB Output Noise Floor Maximum gain setpoint, no RF input −149.5 dBm/Hz RF PIN = −5 dBm, frequency offset = 20 MHz −148 dBm/Hz Output IP3
= 900 MHz, F
F
RF1
= 902.5 MHz, maximum
RF2
gain setpoint Output 1 dB Compression Point Maximum gain setpoint 11.5 dBm Input 1 dB Compression Point Gain setpoint = 0.1 8.5 dBm Gain Flatness Over any 60 MHz bandwidth 0.25 dB Gain Matching At maximum gain setpoint 0.6 dB Phase Matching At maximum gain setpoint ±1 Degrees Input Impedance INPI, INMI, INMQ, INMP (Pins 20, 21, 22, 23)
Output Return Loss
RFOP, RFOM (Pins 9, 10) measured through
balun
FRF = 2400 MHz
Maximum Gain Maximum gain setpoint 7.0 dB Gain Conformance Over gain setpoint of 0.2 to 1.0 0.5 dB Output Noise Floor Maximum gain setpoint, no RF input −147 dBm/Hz RF PIN = −5 dBm, frequency offset = 20 MHz −144 dBm/Hz Output IP3
= 2400 MHz, F
F
RF1
= 2402.5 MHz, maximum
RF2
gain setpoint Output 1 dB Compression Point Maximum gain setpoint 9.6 dBm Input 1 dB Compression Point Gain setpoint = 0.1 4.3 dBm Gain Flatness Over any 60 MHz bandwidth 0.25 dB Gain Matching At maximum gain setpoint 0.8 dB Phase Matching At maximum gain setpoint ±2.5 Degrees Input Impedance INPI, INMI, INMQ, INMP (Pins 20, 21, 22, 23)
Output Return Loss
RFOP, RFOM (Pins 9, 10) measured through
balun
POWER SUPPLY VPRF, VPS2 (Pin 1, 18, 6); RFOP, RFOM (Pins 9, 10)
Positive Supply Voltage 4.75 5 5.25 V
Total Supply Current Includes load current 135 mA
OUTPUT DISABLE DSOP (Pin 13)
Disable Threshold 2.5 V Maximum Attenuation DSOP = 5 V 40 dB Enable Response Time
Delay following high-to-low transition until
device meets full specifications Disable Response Time
Delay following low-to-high transition until
device produces full attenuation
24.2 dBm
200||1
Ohms||pF
8.5 dB
23.3 dBm
180||0.6
Ohms||pF
6.8 dB
18.7 dBm
140||0.5
Ohms||pF
13.5 dB
15 ns
10 ns
Rev. 0 | Page 4 of 24
Page 5
ADL5390

ABSOLUTE MAXIMUM RATINGS

Table 2.
Parameters Rating
Supply Voltage VPRF, VPS2 5.5 V DSOP 5.5 V IBBP, IBBM, QBBP, QBBM 2.5 V RFOP, RFOM 5.5 V RF Input Power at Maximum Gain 10 dBm for 50 Ω
(INPI or INPQ, Single-Ended Drive)
Equivalent Voltage 2.0 V p-p Internal Power Dissipation 825 mW θJA (With Pad Soldered to Board) 59°C/W Maximum Junction Temperature 125°C Operating Temperature Range −40°C to +85°C Storage Temperature Range −65°C to +150°C
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.

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
Page 6
ADL5390

PIN CONFIGURATION AND FUNCTION DESCRIPTIONS

CMRF
INPQ
INMQ
INMI
INPI
24
23 22 21 20 19
CMRF
VPRF
QFLP QFLM QBBP
QBBM
VPS2
1
2
3
4
5
6
ADL5390
TOP VIEW
(Not to Scale)
7 8 9 101112
RFOP
CMOP
CMOP
RFOM
CMOP
CMOP
18
VPRF
17
IFLP
16
IFLM
15
IBBP
14
IBBM
13
DSOP
04954-002
Figure 2. LFCSP Pin Configuration
Table 3. Pin Function Descriptions
Pin No. Mnemonic Description
2, 3 QFLP, QFLM
Q Baseband Input Filter Pins. Connect optional capacitor to reduce Q baseband gain control channel low-
pass corner frequency. 4, 5 QBBP, QBBM Q Channel Differential Baseband Gain Control Inputs. Typical common-mode bias level of 0.5 V. 6, 1, 18 VPS2, VPRF Positive Supply Voltage. VP of 4.75 V to 5.25 V. 7, 8, 11, 12,
CMOP, CMRF Device Common. Connect via lowest possible impedance to external circuit common. 19, 24 9, 10 RFOP, RFOM
Differential RF Outputs. Must be ac-coupled. Differential impedance 50 nominal.
13 DSOP Output Disable. Pull high to disable output stage. Connect to common for normal operation. 14, 15 IBBM, IBBP I Channel Differential Baseband Gain Control Inputs. Typical common-mode bias level of 0.5 V. 16, 17 IFLM, IFLP
I Baseband Input Filter Pins. Connect optional capacitor to reduce I baseband gain control channel low­pass corner frequency.
20, 21 INPI, INMI
I Channel Differential RF Inputs. Must be ac-coupled. 250 impedance to common on each pin. These inputs can be driven single-ended without any performance degradation.
22, 23 INMQ, INPQ
Q Channel Differential RF Inputs. Must be ac-coupled. 250 impedance to common on each pin. These inputs can be driven single-ended without any performance degradation.
Exposed Paddle
GND
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
Page 7
ADL5390

TYPICAL PERFORMANCE CHARACTERISTICS

10
5
0
–5
–10
GAIN (dB)
–15
–20
–25
–30
0.250
0.50
GAIN SETPOINT
FRF = 70MHz
= 140MHz
F
RF
= 380MHz
F
RF
= 900MHz
F
RF
= 2400MHz
F
RF
0.75 1.00
04954-003
5
4 3 2 1
0 –1 –2
CHANNEL GAIN MATCH (dB)
–3
–4 –5
0 300 600 900 1200 1500 1800 2100 2400
+3
σ
–3
σ
FREQUENCY (MHz)
04954-006
Figure 3. Gain Magnitude vs. Gain Setpoint, RF Frequency = 70 MHz,
140 MHz, 380 MHz, 900 MHz, 2400 MHz (Channel I or Channel Q)
10
–5
–10
GAIN (dB)
–15
–20
–25
–30
TEMP = –40°C TEMP = +25°C
5
TEMP = +85°C
0
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
GAIN SETPOINT
04954-004
Figure 4. Gain Magnitude vs. Gain Setpoint, Temp = +85°C, +25°C, −40°C,
RF Frequency = 380 MHz (Channel I or Channel Q)
4
+3σ= DASH LINE
σ
= SOLID LINE
–3
3
2
1
0
–1
GAIN ERROR (dB)
–2
–3
–4
0 0.25 0.50 0.75 1.0
GAIN SETPOINT
FRF = 70MHz FRF = 140MHz F
= 380MHz
RF
= 900MHz
F
RF
F
= 2400MHz
RF
04954-005
Figure 5. Gain Conformance Error vs. Gain Setpoint, RF Frequency = 70 MHz,
140 MHz, 380 MHz, 900 MHz, 2400 MHz
Figure 6. Channel Gain Matching (I to Q) vs. RF Frequency,
Gain Setpoint = 1.0
9
8
7
6
5
4
GAIN (dB)
3
2
1
0
0 300 600 900 1200 1500 1800 2100 2400
FREQUENCY (MHz)
TEMP = –40°C
TEMP = +25°C
TEMP = +85°C
04954-007
Figure 7. Channel Gain vs. RF Frequency, Temp = +85°C, +25°C, −40°C,
Gain Setpoint = 1.0
5
+3σ= DASH LINE
σ
= SOLID LINE
–3
0
–5
–10
PHASE ERROR (Degrees)
–15
–20
0 0.25 0.50 0.75 1.0
GAIN SETPOINT
FRF = 70MHz
= 140MHz
F
RF
F
= 380MHz
RF
= 900MHz
F
RF
= 2400MHz
F
RF
04954-008
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
Page 8
ADL5390
25
20
15
10
–5
–10
PHASE DIFFERRENCE (Degrees)
–15
–20
Figure 9. Channel-to-Channel Phase Matching vs. Gain Setpoint,
RF Frequency = 70 MHz, 140 MHz, 380 MHz, 900 MHz, 2400 MHz
10
8
6
4
2
0
–2
–4
PHASE DIFFERENCE (Degrees)
–6
–8
–10
Figure 10. Channel-to-Channel Phase Matching vs. RF Frequency, Temp =
–142
–143
–144 –145
–146
–147
–148
NOISE (dBm/Hz)
–149
–150
–151
–152
Figure 11. Output Noise Floor vs. Gain Setpoint, No RF Carrier,
RF Frequency = 70 MHz, 140 MHz, 380 MHz, 900 MHz, 2400 MHz
+3σ= DASH LINE –3
σ
= SOLID LINE
5
0
0 0.2 0.4 0.6 0.8 1.0
TEMP = –40°C TEMP = +25°C TEMP = +85°C
0 600 1200 1800 2400
GAIN SETPOINT
+3σ= DASH LINE –3
σ
FREQUENCY (MHz)
FRF= 70MHz F F F F
= SOLID LINE
=140MHz
RF
=380MHz
RF
= 900MHz
RF
= 2400MHz
RF
+85°C, +25°C, −40°C, Gain Setpoint = 1.0
FRF = 70MHz F
= 140MHz
RF
F
= 380MHz
RF
F
= 900MHz
RF
F
= 2400MHz
RF
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
GAIN SETPOINT
04954-009
04954-010
04954-011
–142
–143
–144 –145
–146
–147
–148
NOISE (dBm/Hz)
–149
–150
–151
–152
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
PIN=–10dBm
PIN=–15dBm
GAIN SETPOINT
PIN= –5dBm
NO CARRIER
Figure 12. Output Noise Floor vs. Gain Setpoint, No Carrier, with Carrier
(20 MHz Offset), RF P
–142
–143
–144 –145
–146
–147
–148
NOISE (dBm/Hz)
–149
–150
–151
–152
0 400 800 1200 1600 2000 2400
= −5, −10, −15, No Carrier, RF Frequency = 380 MHz
IN
GAIN SETPOINT = 1.0
FREQUENCY (MHz)
Figure 13. Output Noise Floor vs. RF Frequency, Gain Setpoint = 1.0,
No RF Carrier
10
5
0
–5
GAIN (dB)
–10
–15
–20
0 400 800 1200 1600 2000 2400
GAIN SETPOINT = 1.0
GAIN SETPOINT = 0.5
GAIN SETPOINT = 0.1
FREQUENCY (MHz)
Figure 14. Gain vs. RF Frequency, Gain Setpoint = 1.0, 0.5, 0.1
04954-012
04954-013
04954-014
Rev. 0 | Page 8 of 24
Page 9
ADL5390
0
–10
–20 –30
–40
–50
–60
–70
–80
RF OUTPUT SIDEBAND POWER (dBm)
–90
–100
0 100 200 300 400 500 600 700 800 900 1000
DIFF. BASEBAND INPUT LEVEL (mV p-p)
FUNDAMENTAL
2ND HARMONIC
3RD HARMONIC
04954-015
Figure 15. Baseband Harmonic Distortion, (Channel I and Channel Q),
RF P
= −5 dBm, (Balun and Cable Losses Not Included)
IN
12
11
10
9
OP1dB (dBm)
8
7
6
0
400 800 1200 1600 2000 2400
FREQUENCY (MHz)
TEMP = –40°C
TEMP = +25°C
TEMP = +85°C
04954-016
0
–5
–10
–15
–20
–25
SIDEBAND POWER (dBm)
–30
–35
0 50 100 150 200 250 300 350 400
1V p-p BASEBAND INPUT
500mV p-p BASEBAND INPUT
250mV p-p BASEBAND INPUT
BB FREQUENCY (MHz)
Figure 18. IQ Modulation Bandwidth vs. Baseband Magnitude
15
10
5
0
–5
OP1dB (dBm)
–10
–15
–20
–25
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
GAIN SETPOINT
FRF = 70MHz
= 140MHz
F
RF
= 380MHz
F
RF
= 900MHz
F
RF
= 2400MHz
F
RF
04954-018
04954-019
Figure 16. Output 1 dB Compression Point vs. RF Frequency,
Temp = +85°C, +25°C, −40°C, Gain Setpoint = 1.0
30
28
TEMP = –40°C
26 24 22
20
OIP3 (dBm)
18 16
14
12
10
0
TEMP = +85°C
400 800 1200 1600 2000 2400
FREQUENCY (MHz)
TEMP = +25°C
04954-017
Figure 17. Output IP3 vs. RF Frequency, Temp = +85°C, +25°C, −40°C,
Gain Setpoint = 1.0
Rev. 0 | Page 9 of 24
Figure 19. Output 1 dB Compression vs. Gain Setpoint, RF Frequency =
70 MHz, 140 MHz, 380 MHz, 900 MHz, 2400 MHz
30
25
20
15
10
5
OIP3 (dBm)
0
–5
–10
–15
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
GAIN SETPOINT
FRF = 70MHz
= 140MHz
F
RF
F
= 380MHz
RF
= 900MHz
F
RF
F
= 2400MHz
RF
04954-020
Figure 20. Output IP3 vs. Gain Setpoint, RF Frequency = 70 MHz, 140 MHz,
380 MHz, 900 MHz, 2400 MHz
Page 10
ADL5390
300
250
200
150
100
INPUT SHUNT RESISTANCE (Ω)
50
20 220 420 620 820 1020 12201420 16201820 2020 2220
Figure 21. S11 of RF Input (Shunt R/C Representation)
SHUNT CAPACITANCE (pF)
SHUNT RESISTANCE ()
F
(MHz)
RF
1.25
1.00
0.75
0.50
0.25
0
INPUT SHUNT CAPACITANCE (pF)
04954-021
0
–5 –10 –15 –20 –25 –30 –35 –40 –45 –50
RF OUTPUT POWER (dBm)
–55 –60 –65 –70 –75
0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0
DSOP VOLTAGE (V)
Figure 24. Power Shutdown Attenuation, RF = 380 MHz
04954-024
ADL5390 SDD22
90
60
30
330
300
)
I
150
|GRIDZ|
S
11TERMANG
I
210
IMPEDANCE CIRCLE SDD22 NOM WFR DUT 1 S22 NOM WFR
120
240
10MHz
ARG(
GRIDZ
2.7GHz
10MHz
270
), RADS(S
3GHz
11
TERMANG
Figure 22. S22 of RF Output (Differential and Single-Ended through Balun)
139
138
Vp = 5.25
1
0
0180
04954-022
TEK RUN ENVELOPE 12 AUG 04 16:48:01
1
CH1 500mV CH3 2.0V D
S
M 10.0ns 5.0GS/s ET 200ps/pt A CH3 760mV
04954-025
Figure 25. Power Shutdown Response Time, RF = 380 MHz
137
136
135
134
SUPPLY CURRENT (mA)
133
132
–40 –25 –10 5 20 35 50 65 80
Vp = 5
Vp = 4.75
TEMPERATURE (°C)
Figure 23. Supply Current vs. Temperature
04954-023
Rev. 0 | Page 10 of 24
Page 11
ADL5390

GENERAL STRUCTURE

THEORY OF OPERATION

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.
Since the two independent RF/IF inputs can be combined in arbitrary proportions, the overall function can be termed “vector multiplication” as expressed by
= V
V
OUT
IRF
× (V
where:
V V
IRF
IBB
and V and V
are the RF/IF input vectors.
QRF
are the baseband input scalars.
QBB
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 V 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.
IBB/VO
) + V
QRF
× (V
QBB/VO
)
of
I (Q)BB
,
V
IRF
I CHANNEL
SINGLE-ENDED
OR DIFFERENTIAL
V
,
QRF
Q CHANNEL
SINGLE-ENDED
OR DIFFERENTIAL
Figure 26. Simplified Architecture of the ADL5390

NOISE AND DISTORTION

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.
175
DYNAMIC RANGE = OIP3 – (OUTPUT NOISE FLOOR (NO CARRIER))
170
BASEBAND INPUT
V-I
ATTENUATOR
V-I
ATTENUATOR
BASEBAND INPUT
I CHANNEL
V
IBB
LINEAR
LINEAR
V
QBB
Q CHANNEL
I-V
OUTPUT
DISABLE
SINGLE-ENDED OR DIFFERENTIAL 50 OUTPUT
04954-026
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°.
Rev. 0 | Page 11 of 24
165
Hz)
×
160
155
150
DYNAMIC RANGE (dB
145
140
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
GAIN SETPOINT
Figure 27. Dynamic Range Variation with Gain Setpoint
04954-027
Page 12
ADL5390

APPLICATIONS

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.

RF INPUT AND MATCHING

The RF/IF inputs present 250 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
RFIN_I
RFIN_Q
66.5
R22
66.5
C7
VP
R2
C2
10nF
C5
10nF
0.1µF
L1 0
L2 0
VP
C4
0.1µF
C1
10nF
C6
10nF
100pF
C8 100pF
C3
VPRF
CMRF
INPI
INMI
IPMQ
INPQ
CMRF
VPRF
C12
(SEE TEXT)
IFLP
IFLM
ADL5390
P L F
QFLM
Q
C11
(SEE TEXT)
QBBP QBBM
Figure 29. Basic Connections
IBBMIBBP
IBBP
QBBP
IBBM
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.
0
876.8
C18
972.0
1067.2
1162.4
(M/A-COM)
S11 MATCH WITHOUT
66.5 TERMINATION
1448.0
1352.8
T1
1543.2
4
1733.6
1638.4
1828.8
1924.0
1257.6
15
3
ETC1-1-13
2114.4
2019.2
2209.6
RFOP
–5
–10
–15
dB
–20
400.8
591.2
496.0
S11 MATCH WITH TERMINATION
686.4
781.6
FREQUENCY (MHz)
–25
–30
–35
20.0
115.2
210.4
305.6
Figure 28. ADL5390 Customer Evaluation Board RF Input Return Loss.
VP
B
SW1
DSOP
CMOP
CMOP
RFOM
RFOP
CMOP
CMOP
VPS2
QBBM
C10
100pFC90.1µF
R8 10k
120nH
C14
0.1µF
L4
A
L3 120nH
VP
10nF
C17
10nF
2400.0
2304.8
04954-029
04954-028
Rev. 0 | Page 12 of 24
Page 13
ADL5390
±

RF OUTPUT AND MATCHING

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.
V
P
0.1µF
RFOP
120nH
10pF
10pF
50
DIFFERENTIAL
1:1
RF OUTPUT
04954-030
R
T
RFOM
I
G
SIG
Figure 30. RF Output Interface to the ADL5390 Showing
M
R
T
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.
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.
10
8
6
4
2
GAIN (dB)
0
–2
–4
RL = 50
–10
10 100 1000 10000
Figure 31. Gain of the ADL5390 Using a Single-Ended Output with Different
Dummy Loads, R
on the Unused Output, Gain Setpoint = 1.0
L2
RL2 = OPEN
R
L2
R
L2
FREQUENCY (MHz)
= 50
= SHORT
04954-043
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.

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
Page 14
ADL5390
The 3 dB bandwidth is set by choosing C following equation:
nF10kHz45
external
×
pF0.5
+
f
dB3
C
This equation has been verified for values of C
0.1 µF (bandwidth settings of approximately 4.5 kHz to 43 MHz).

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.
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.
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:
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:
=SwingScaleFull
according to the
FLT
from 10 pF to
FLT
AD9777 ADL5390
I
OUTA1
I
OUTB1
I
OUTA2
I
OUTB2
R1
R2
R1
R2
OPTIONAL
LOW-PASS
FILTER
OPTIONAL LOW-PASS
FILTER
R3
R3
IBBP
IBBM
QBBP
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
DIFFERENTIAL PEAK-PEAK SWING (R3) (V p-p)
0.70
R3 ()
13050 55 60 65 70 75 80 85 90 100105 115 120110 12595
04954-033
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.
04954-032
MAX
R2
+
⎤ ⎥
R3R2
()()
1||2
R3R2R1I
×+×
⎢ ⎢
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
Page 15
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 (I and Q
) become the in-phase (I) and quadrature (Q) base-
BBP/M
BBP/M
band 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 90
o
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 90
o
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 90
o
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

V
q
MAX GAIN = 5dB
+0.5
|A|
A
θ
V
i
+0.5–0.5
inputs V
IBB
and V 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 90 power splitter will directly affect this representation and could be seen as an offset and skew of the circle.
A change in sign of V 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 V metric identities
where:
V
is the baseband scaling constant (285 mV).
O
V
and V
IBB
QBB
centered around 500 mV, respectively (V V
= V
QBB
QBBP
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 V concert to modulate the gain and the phase.
. The resultant of their vector sum represents
QBB
o
) accuracy of the 90o
or V
IBB
IBB
IBB
QBB
can be viewed as a change in
QBB
and V
)
is given by simple trigono-
QBB
22
//
VVVVGain +=
OQBBO
]
()
VVarctanPhase /
IBB
are the differential I and Q baseband voltages
= V
V
IBBP
IBBM
are needed in
QBB
V
QBBM
).
and V
IBB
IBB
;
Pure amplitude modulation is represented by radial movement of the gain vector tip at a fixed angle, while pure phase modula-
MIN GAIN < –30dB
–0.5
Figure 34. Vector Gain Representation
04954-034
The ADL5390 can be used as a vector modulator by driving the RF I and Q inputs single-ended through a 90
o
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
tion 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 90 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
o
signal (forward pilot, sync, paging, and six traffic as per
Rev. 0 | Page 15 of 24
Page 16
ADL5390
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 V
= V
IBB
V
IBBM
= 0.353 V (centered around 500 mV), i.e., V
QBB
= V
QBBP
− V
= 0.353 V. Adjacent channel power is
QBBM
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.
REF LVL 5dBm
0.7dB OFFSET
0
–10
–20
–30
1AVG
–40
–50
–60
–70
Cl2
–80
–90
100
CENTER 880MHz 500kHz/ SPAN 5MHz
Figure 35. Output Spectrum, Single-Carrier CDMA2000 Test Model at −5 dBm,
= VQ = 0.353 V, ACP Measured at 750 kHz and 1.98 MHz Carrier Offset,
V
I
Input Signal–Filtered Using a Cavity-Tuned Filter (Pass Band = 4.6 MHz)
Cl2
MARKER 1 [T1] –14.38dBm
880.00755511MHz
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.
–30
–40
o
. P
is equal to 0 dBm and
OUT
IBBP
RBW 30kHz VWB 300kHz SWT 2s
1
C0
Cl1
Cl1
RF ATT 20dB MIXER –10dBm UNIT 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
C0
CU1
CU1
CU2
A
1RM
EXT
CU2
04954-035
–30
–40
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.
With a fixed input power of 2.16 dBm, the output power was again swept by changing V
and V
IBB
from 0 V to 500 mV.
QBB
The resulting output power, ACP, and noise floor are shown in Figure 37.
5
–2
–9
–16
–23
–30
RF OUTPUT POWER (dBm)
–37
–44
0 0.1 0.2 0.3 0.4 0.5
ACP: 1.98MHz OFFSET, 30kHz RBW
NOISE: 4MHz OFFSET, 1MHz RBW
V
vs. V
OUT
IBB/VQBB
ACP: 750kHz OFFSET, 30kHz RBW
V
I(Q)BB
Figure 37. Output Power, Noise, and ACP vs. I and Q Control Voltages,
CDMA2000 Test Model, V
= VQ, ACP Measured in 30 kHz RBW at ±750 MHz
I
and ±1.98 MHz Carrier Offset, Noise Measured at ±4 MHz Carrier Offset
–30
–40
–50
–60
–70
–80
–90
–100
ACP (dBc)
NOISE (dBm @ 4MHz Carrier Offset)
04954-045
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.
–50
–60
–70
ACP (dBc)
–80
–90
–100
–30 –25 –20 –15 –10 –5 0 5
ACP: 1.98MHz OFFSET, 30kHz RBW
NOISE: 4MHz OFFSET, 1MHz RBW
ACP: 750kHz OFFSET, 30kHz RBW
OUTPUT POWER (dBm)
–50
–60
–70
–80
–90
–100
NOISE (dBm @ 4MHz Carrier Offset)
04954-044
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
Page 17
ADL5390
1
234

QUADRATURE MODULATOR

The ADL5390 can be used as a quadrature modulator by driving the RF I and Q inputs (INPI and INPQ) single-ended through a
o
90
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.
I DATA
LO IN
50
SUM PORT
QCN-12
TERM PORT
90° PHASE SPLITTER
PORT 1
PORT 2
10nF
66.5
10nF
66.5
INPI
INPQ
Figure 38. Quadrature Modulator Application
Single sideband performance of a quadrature modulator is determined by the magnitude and phase balance (compared to
o
a 90
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 90 single sideband performance can be achieved by choosing a well-balanced 90
o
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 90
o
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.
IBBP
IBBM
RFOM
ADL5390
Q DATA
RFOP
QBBP
QBBM
o
phase splitter. Good
10nF
10nF
(M/A-COM)
15
34
ETC1-1-13
ROFP
*
RBW 3kHz VWB 10kHz SWT 780ms
A
1
4
04954-039
1 AP CLRWR
REF 7dBm ATT 35dB
DESIRED SIDEBAND –16.20dBm
0
900.998397436MHz UNDESIRED SIDEBAND
–10
–23.27dB –1.996794872MHz
–20
THIRD BASEBAND HARMONIC –37.38dB
–30
–4.004807692MHz LO FEEDTHROUGH
–40
–41.27dB –998.397435897kHz
–50
3
–60
–70
-80
-
CENTER 900MHz 700kHz/ SPAN 7MHz
2
Figure 39. SSB Quadrature Modulator Result Us ing External 90° Phase Splitter,
= −15 dBm, VIBB = VQBB = 0.5 V
RF P
IN
(With Reference to a Common-Mode Voltage of 0.5 V )
*
RBW 3kHz
REF 7dBm ATT 35dB
DESIRED SIDEBAND
0
04954-038
1 AP CLRWR
–16.78dBm
900.998397436MHz UNDESIRED SIDEBAND
–10
–51.81dB –1.996794872MHz
–20
THIRD BASEBAND HARMONIC –38.45dB
–30
–4.004807692MHz LO FEEDTHROUGH
–40
–41.49dB –998.397435897kHz
–50
–60
–70
–80
–90
CENTER 900MHz 700kHz/ SPAN 7MHz
VWB 10kHz SWT 780ms
A
04954-046
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 O ffset by 3
o
, 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 90
o
phase splitters—AD8340, AD8341, AD8345, AD8346, AD8349—that cover a variety of frequency bands.
Rev. 0 | Page 17 of 24
Page 18
ADL5390
RBW 10kHz
*
VBW 300kHz
REF –26.6dBm
1 RM AVG
*
–100
–110
–120
–30 –40
–50
–60
–70
–80 –90
POS –26.623dBm
CENTER 880MHz 1.29MHz/ SPAN 12.9MHz
STANDARD: CDMA IS95C CLASS 0 FWD Tx CHANNELS
CH1 (REF) CH2 CH3
TOTAL
ATT 5dB
*
–22.93dBm –22.83dBm –22.95dBm
–18.13dBm
*
SWT 4s
*
ADJACENT CHANNEL
LOWER –59.25dB UPPER –59.43dB
ALTERNATE CHANNEL
LOWER –62.79dB UPPER –63.11dB
2ND ALTERNATE CHANNEL
LOWER –60.71dB UPPER –60.32dB
A
NOR
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 V
–69
–70
–71
–72
–73
–74
–75
NOISE (dBC) (1MHz RBW)
–76
–77
–78
–25 –20 –15 –10 –5 0
NOISE (dBc) - 8MHz OFFSET - 1MHz RBW
, 3-Carrier CDMA2000 I/Q Data
P-P
OUTPUT POWER (dBm)
04954-031
Figure 42. Noise vs. Output Power
04954-037

RF MULTIPLEXER

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 V ence to a common-mode voltage of 0.5 V). The INPI signal is presented to the output. Then, when V
0.0 and V Lastly, as V the output. With V
remains equal to zero, there is no RF output.
QBB
transitions to 0.5 V, the INPQ signal appears at
QBB
= 0.0 and V
IBB
output is typically >40 dB at 380 MHz.
TEK STOPPED 200 Acqs 24 AUG 04 11:08:40
CH2
2
CH3 CH1
3
1
CH1 200mV CH2 500mV D CH3 500mV D
S
Figure 43. ADL5390 in RF Multiplexer Application
= 0.5 and V
IBB
= 0.0, the isolation to the
QBB
V
IBB
V
QBB
RF OUTPUT
M 40.0ns 1.25GS/s 800ps/pt
S
A CH2 780mV
= 0.0 (with refer-
QBB
transitions to V
IBB
IBB
04954-047
=
Rev. 0 | Page 18 of 24
Page 19
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
nF10kHz45
external
×
pF0.5
+
f
dB3
C
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
Page 20
ADL5390
Table 4. Evaluation Board Configuration Options
Component Function Default Conditions
R7, R9, R11, R14, R15, R19, R20, R21, C15, C19, W3, W4
R1, R3, R10, R12, R13, R16, R17, R18, C16, C20, W1, W2
C11, C12
T1, C17, C18, L3, L4
C2, C1, R2 C5, C6, R22
R4, R6, R5, C4, C7 C9, C3, C8, C10
R8, SW1
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).
Q Channel Baseband Interface. See the I Channel Baseband Interface section.
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.
Power Supply Decoupling.
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.
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 10 (size 0603)
C5 = C6 = 10 nF (size 0603) R22 = 66.5 10 (size 0603)
R4, R6, R5 = 0 Ω (size 0603) C4, C7 C9 = 0.1uF (size 0603) C3, C8, C10 = 100 pF (size 0603)
R8 = 10 kΩ (size 0603) SW1 = SPDT (Position A, output enabled)
Rev. 0 | Page 20 of 24
Page 21
ADL5390
RFIN_I
RFIN_Q
VP
66.5
R22
66.5
R8 10k
L4
VP
TEST POINT
B
SW1
A
L3 120nH
VP
IBBMIBBP
W4
0.1µF
R14
4k
IFLM
QFLM
C15
R19 0
R11 2k
IBBP
QBBP
C19
0.1µF
W3
IBBM
QBBM
R15
44k
DSOP
CMOP
CMOP
RFOM
RFOP
CMOP
CMOP
VPS2
100pF
R7
(OPEN)
R20
0
C10
VP
120nH
C14
0.1µF
R6 0
C9
0.1µF
R9
(OPEN)
R21
0
C1
10nF
C6
10nF
R4 0
100pF
C8 100pF
C3
VPRF
CMRF
INPI
INMI
IPMQ
INPQ
CMRF
VPRF
C12
(OPEN)
IFLP
ADL5390
P L F Q
C11
(OPEN)
C7
R5
0.1µF
0
L1 0
R2
C2
10nF
L2 0
C5
10nF
VP
C4
0.1µF
C18
10nF
C17
10nF
GND
TEST POINT
15
3
T1
ETC1-1-13
(M/A-COM)
DSOP
4
RFOP
R12
R10 2k
R16 0
C20
0.1µF
R13
44k
W1
VP
R18
0
R3
(OPEN)
QBBM
04954-040
QBBP
R17
0
R1
(OPEN)
4k
C16
0.1µF
W2
Figure 44. Evaluation Board Schematic
Rev. 0 | Page 21 of 24
Page 22
ADL5390
04954-041
04954-042
Figure 45. Component Side Layout
Figure 46. Component Side Silkscreen
Rev. 0 | Page 22 of 24
Page 23
ADL5390

OUTLINE DIMENSIONS

0.60 MAX
19
18
EXPOSED
(BOTTOMVIEW)
13
12
PA D
24
6
7
1
2.50 REF
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
0.05 MAX
0.02 NOM COPLANARITY
0.60 MAX
0.50 BSC
0.50
0.40
0.30
0.08
Figure 47. 24-Lead Lead Frame Chip Scale Package [LFCSP]
4 × 4 mm Body
(CP-24-2)
Dimensions shown in millimeters

ORDERING GUIDE

Models Temperature Range Package Description Package Option Order Multiple
ADL5390ACPZ-WP ADL5390ACPZ-REEL71 −40°C to +85°C 24-Lead Lead Frame Chip Scale Package (LFCSP) CP-24-2 1,500 ADL5390-EVAL Evaluation Board 1
1
Z = Pb-free part.
2
WP = waffle pack.
1, 2
−40°C to +85°C 24-Lead Lead Frame Chip Scale Package (LFCSP) CP-24-2 64
Rev. 0 | Page 23 of 24
Page 24
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
Loading...