Document Outline
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- INPUT COUPLING USING A SERIES RESISTOR
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- OUTPUT DRIVE CAPABILITY AND BUFFERING
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- DEVICE CALIBRATION AND ERROR CALCULATION
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- EVALUATION BOARD
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100 MHz to 6 GHz
TruPwrTM Detector
ADL5500
Rev. A
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781.329.4700
www.analog.com
Fax: 781.461.3113
©2006 Analog Devices, Inc. All rights reserved.
FEATURES
True rms response
Excellent temperature stability
±0.1 dB accuracy vs. temperature over top 8 dB of input range
Up to 30 dB input dynamic range at 3.9 GHz
50 input impedance
1250 mV rms, +15 dBm, maximum input
Single-supply operation: 2.7 V to 5.5 V
Low power: 3 mW at 3 V supply
RoHS compliant
APPLICATIONS
Measurement of CDMA2000, W-CDMA, and QPSK-/QAM-
based OFDM, and other complex modulation waveforms
RF transmitter or receiver power measurement
5
0.03
25
15
05546-001
INPUT (dBm)
OUTPUT (V)
0.1
1
20
15
10
5
0
5
10
Figure 1. Output vs. Input Level, Supply 3 V, Frequency 1.9 GHz
GENERAL DESCRIPTION
The ADL5500 is a mean-responding power detector for use
in high frequency receiver and transmitter signal chains from
100 MHz to 6 GHz. It is easy to apply, requiring only a single
supply between 2.7 V and 5.5 V and a power supply decoupling
capacitor. The input is internally ac-coupled and has a nominal
input impedance of 50 . The output is a linear-responding dc
voltage with a conversion gain of 6.4 V/V rms at 900 MHz. The
on-chip, 1 k series resistance at the output combined with an
external shunt capacitor creates a low-pass filter response that
reduces the residual ripple in the dc output voltage.
The ADL5500 is intended for true power measurement of
simple and complex waveforms. The device is particularly
useful for measuring high crest factor (high peak-to-rms ratio)
signals, such as CDMA2000, W-CDMA, and QPSK/QAM-
based OFDM waveforms.
The ADL5500 offers excellent temperature stability with near
0 dB measurement error across temperature. The high accuracy
range, centered around +3 dBm at 900 MHz, offers ±0.1 dB
error from -40°C to +85°C over an 8.5 dB range. The ADL5500
reduces calibration requirements with low drift across a 30 dB
range over temperature and process variations.
The ADL5500 operates from -40°C to +85°C and is available in
a 4-ball, 1.0 mm × 1.0 mm wafer-level chip scale package. It is
fabricated on a proprietary high f
T
silicon bipolar process.
FUNCTIONAL BLOCK DIAGRAM
RFIN
BUFFER
VPOS
VRMS
COMM
ERROR
AMP
x
2
x
2
i
i
TRANS-
CONDUCTANCE
CELLS
ADL5500
1k
05546-002
INTERNAL FILTER
CAPACITOR
Figure 2.
ADL5500
Rev. A | Page 2 of 24
TABLE OF CONTENTS
Features .............................................................................................. 1
Applications....................................................................................... 1
General Description ......................................................................... 1
Functional Block Diagram .............................................................. 1
Revision History ............................................................................... 2
Specifications..................................................................................... 3
Absolute Maximum Ratings............................................................ 7
ESD Caution.................................................................................. 7
Pin Configuration and Function Descriptions............................. 8
Typical Performance Characteristics ............................................. 9
Circuit Description......................................................................... 14
Filtering........................................................................................ 14
Applications..................................................................................... 15
Basic Connections ...................................................................... 15
Output Swing .............................................................................. 15
Linearity....................................................................................... 15
Input Coupling Using a Series Resistor................................... 16
Multiple RF Inputs ..................................................................... 16
Selecting the Output Low-Pass Filter Network ...................... 16
Power Consumption and Power-On/-Off Response............. 16
Output Drive Capability and Buffering................................... 17
VRMS Output Offset ................................................................. 17
Device Calibration and Error Calculation.............................. 18
Calibration for Improved Accuracy......................................... 18
Drift over a Reduced Temperature Range .............................. 19
Operation Above 4.0 GHz......................................................... 19
Device Handling......................................................................... 19
Evaluation Board ........................................................................ 20
Outline Dimensions ....................................................................... 22
Ordering Guide .......................................................................... 22
REVISION HISTORY
2/06--Rev 0 to Rev. A
Changes to Features.......................................................................... 1
Changes to Table 2............................................................................ 7
Changes to Figure 5.......................................................................... 9
Changes to Figure 28 and Figure 31............................................. 13
Changes to Figure 35 Caption....................................................... 15
Changes to Power Consumption and Power-On/-Off
Response Section ............................................................................ 16
Changes to Figure 48...................................................................... 20
Changes to Ordering Guide .......................................................... 22
7/05--Revision 0: Initial Version
ADL5500
Rev. A | Page 3 of 24
SPECIFICATIONS
T
A
= 25°C, V
S
= 3.0 V, C
FLT
= 10 nF, light condition 600 LUX, unless otherwise noted.
Table 1.
Parameter Condition
Min
Typ
Max
Unit
FREQUENCY RANGE
Input RFIN
100
6000
MHz
RMS CONVERSION (f = 100 MHz)
Input RFIN to output VRMS
Input Impedance
94||3
||pF
Input Return Loss
10
dB
Dynamic Range
1
CW input, -40°C < T
A
< +85°C
±0.1 dB Error
2
Delta from 25°C, V
S
= 5 V
5
dB
±0.25 dB Error
3
V
S
= 3 V
17.5
dB
V
S
= 5 V
20
dB
±1 dB Error
3
V
S
= 3 V
25
dB
V
S
= 5 V
29
dB
±2 dB Error
3
V
S
= 3 V
28.5
dB
V
S
= 5 V
33
dB
Maximum Input Level
±0.25 dB error
3
6
dBm
Minimum Input Level
±1 dB error
3
-18.5 dBm
Conversion Gain
VOUT = (Gain × V
IN
) + Intercept
6.1
V/V rms
V
S
= 5 V
4.6
7.2
V/V rms
Output Intercept
4
0.03
V
V
S
= 5 V
-20
+100
mV
Output Voltage--High Power In
P
IN
= +5 dBm, 400 mV rms
2.43
V
Output Voltage--Low Power In
P
IN
= -21 dBm, 20 mV rms
0.14
V
Temperature Sensitivity
P
IN
= -5 dBm
25°C
T
A
85°C
0.0032
dB/°C
-40°C
T
A
+25°C
-0.0042
dB/°C
RMS CONVERSION (f = 450 MHz)
Input RFIN to output VRMS
Input Impedance
75||1.4
||pF
Input Return Loss
12.5
dB
Dynamic Range
1
CW input, -40°C < T
A
< +85°C
±0.1 dB Error
2
Delta from 25°C, V
S
= 5 V
8
dB
±0.25 dB Error
3
V
S
= 3 V
19
dB
V
S
= 5 V
24
dB
±1 dB Error
3
V
S
= 3 V
24.5
dB
V
S
= 5 V
29
dB
±2 dB Error
3
V
S
= 3 V
27.5
dB
V
S
= 5 V
33
dB
Maximum Input Level
±0.25 dB error
3
5
dBm
Minimum Input Level
±1 dB error
3
-19.5 dBm
Conversion Gain
VOUT = (Gain × V
IN
) + Intercept
6.9
V/V rms
Output Intercept
4
0.03
V
Output Voltage--High Power In
P
IN
= +5 dBm, 400 mV rms
2.8
V
Output Voltage--Low Power In
P
IN
= -21 dBm, 20 mV rms
0.16
V
Temperature Sensitivity
P
IN
= -5 dBm
25°C
T
A
85°C
0.0020
dB/°C
-40°C
T
A
+25°C
-0.0023
dB/°C
ADL5500
Rev. A | Page 4 of 24
Parameter Condition
Min
Typ
Max
Unit
RMS CONVERSION (f = 900 MHz)
Input RFIN to output VRMS
Input Impedance
62||1.1
||pF
Input Return Loss
13
dB
Dynamic Range
1
CW input, -40°C < T
A
< +85°C
±0.1 dB Error
2
Delta from 25°C, V
S
= 5 V
8.5
dB
±0.25 dB Error
3
V
S
= 3 V
19.5
dB
V
S
= 5 V
23
dB
±1 dB Error
3
V
S
= 3 V
24.5
dB
V
S
= 5 V
29
dB
±2 dB Error
3
V
S
= 3 V
28
dB
V
S
= 5 V
32
dB
Maximum Input Level
±0.25 dB error
3
6
dBm
Minimum Input Level
±1 dB error
3
-19 dBm
Conversion Gain
VOUT = (Gain × V
IN
) + Intercept
6.4
V/V rms
Output Intercept
4
0.04
V
Output Voltage--High Power In
P
IN
= +5 dBm, 400 mV rms
2.61
V
Output Voltage--Low Power In
P
IN
= -21 dBm, 20 mV rms
0.15
V
Temperature Sensitivity
P
IN
= -5 dBm
25
°C T
A
+85°C
0.0018
dB/°C
-40°C
T
A
+25°C
-0.0023
dB/°C
RMS CONVERSION (f = 1900 MHz)
Input RFIN to output VRMS
Input Impedance
43||0.9
||pF
Input Return Loss
11.5
dB
Dynamic Range
1
CW input, -40°C < T
A
< +85°C
±0.1 dB Error
2
Delta from 25°C, V
S
= 5 V
7
dB
±0.25 dB Error
3
V
S
= 3 V
20
dB
V
S
= 5 V
23
dB
±1 dB Error
3
V
S
= 3 V
26
dB
V
S
= 5 V
30
dB
±2 dB Error
3
V
S
= 3 V
31.5
dB
V
S
= 5 V
33
dB
Maximum Input Level
±0.25 dB error
3
8
dBm
Minimum Input Level
±1 dB error
3
-19.5 dBm
Conversion Gain
VOUT = (Gain × V
IN
) + Intercept
5.0
V/V rms
Output Intercept
4
0.02
V
Output Voltage--High Power In
P
IN
= +5 dBm, 400 mV rms
2.02
V
Output Voltage--Low Power In
P
IN
= -21 dBm, 20 mV rms
0.11
V
Temperature Sensitivity
P
IN
= -5 dBm
25°C
T
A
85°C
0.0017
dB/°C
-40°C
T
A
+25°C
-0.0031
dB/°C
ADL5500
Rev. A | Page 5 of 24
Parameter Condition
Min
Typ
Max
Unit
RMS CONVERSION (f = 2350 MHz)
Input RFIN to output VRMS
Input Impedance
37||0.9
||pF
Input Return Loss
9
dB
Dynamic Range
1
CW input, -40°C < T
A
< +85°C
±0.1 dB Error
2
Delta from 25°C, V
S
= 5 V
5
dB
±0.25 dB Error
3
V
S
= 3 V
5
dB
V
S
= 5 V
10
dB
±1 dB Error
3
V
S
= 3 V
28.5
dB
V
S
= 5 V
32
dB
±2 dB Error
3
V
S
= 3 V
32
dB
V
S
= 5 V
36
dB
Maximum Input Level
±0.25 dB error
3
8
dBm
Minimum Input Level
±1 dB error
3
-19.5 dBm
Conversion Gain
VOUT = (Gain × V
IN
) + Intercept
4.5
V/V rms
Output Intercept
4
0.02
V
Output Voltage--High Power In
P
IN
= +5 dBm, 400 mV rms
1.82
V
Output Voltage--Low Power In
P
IN
= -21 dBm, 20 mV rms
0.11
V
Temperature Sensitivity
P
IN
= -5 dBm
25°C
T
A
85°C
0.0027
dB/°C
-40°C
T
A
+25°C
-0.0046
dB/°C
RMS CONVERSION (f = 2700 MHz)
Input RFIN to output VRMS
Input Impedance
34||0.8
||pF
Input Return Loss
8.5
dB
Dynamic Range
1
CW input, -40°C < T
A
< +85°C
±0.1 dB Error
2
Delta from 25°C, V
S
= 5 V
5
dB
±0.25 dB Error
3
V
S
= 3 V
5
dB
V
S
= 5 V
8.5
dB
±1 dB Error
3
V
S
= 3 V
28.5
dB
V
S
= 5 V
32
dB
±2 dB Error
3
V
S
= 3 V
33
dB
V
S
= 5 V
36
dB
Maximum Input Level
±0.25 dB error
3
9
dBm
Minimum Input Level
±1 dB error
3
-19.5 dBm
Conversion Gain
VOUT = (Gain × V
IN
) + Intercept
4.2
V/V rms
Output Intercept
4
0.02
V
Output Voltage--High Power In
P
IN
=+5 dBm, 400 mV rms
1.67
V
Output Voltage--Low Power In
P
IN
= 21 dBm, 20 mV rms
0.1
V
Temperature Sensitivity
P
IN
= 5 dBm
25°C
T
A
85°C
0.0030
dB/°C
-40°C
T
A
+25°C
-0.0049
dB/°C
ADL5500
Rev. A | Page 6 of 24
Parameter Condition
Min
Typ
Max
Unit
RMS CONVERSION (f = 3900 MHz)
Input RFIN to output VRMS
Input Impedance
30||0.6
||pF
Input Return Loss
9
dB
Dynamic Range
1
CW input, -40°C < T
A
< +85°C
±0.1 dB Error
2
Delta from 25°C, V
S
= 5 V
2
dB
±0.25 dB Error
3
V
S
= 3 V
5.5
dB
V
S
= 5 V
8
dB
±1 dB Error
3
V
S
= 3 V
28.5
dB
V
S
= 5 V
32
dB
±2 dB Error
3
V
S
= 3 V
34
dB
V
S
= 5 V
36.5
dB
Maximum Input Level
±0.25 dB error
3
12
dBm
Minimum Input Level
±1 dB error
3
-17 dBm
Conversion Gain
VOUT = (Gain × V
IN
) + Intercept
3.2
V/V rms
Output Intercept
4
0.02
V
Output Voltage--High Power In
P
IN
= +5 dBm, 400 mV rms
1.28
V
Output Voltage--Low Power In
P
IN
= 21 dBm, 20 mV rms
0.08
V
Temperature Sensitivity
P
IN
= 5 dBm
25°C
T
A
85°C
0.0035
dB/°C
-40°C
T
A
+25°C
-0.0066
dB/°C
OUTPUT OFFSET
No signal at RFIN
40
150
mV
POWER SUPPLIES
Operating Range
-40°C < T
A
< +85°C
2.7
5.5
V
Quiescent Current
No signal at RFIN
5
1.0
mA
1
The available output swing, and hence the dynamic range, is altered by the supply voltage; see Figure 8.
2
Error referred to delta from 25°C response; see Figure 16 through Figure 21.
3
Error referred to best-fit line at 25°C
4
Calculated using linear regression.
5
Supply current is input level dependant; see Figure 6.
ADL5500
Rev. A | Page 7 of 24
ABSOLUTE MAXIMUM RATINGS
Table 2.
Parameter Rating
Supply Voltage V
S
5.5 V
VRMS
0 V, V
S
RFIN 1.25
V
rms
Equivalent Power, re 50
15 dBm
Internal Power Dissipation
150 mW
JA
(WLCSP)
260°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.
ADL5500
Rev. A | Page 8 of 24
PIN CONFIGURATION AND FUNCTION DESCRIPTIONS
VRMS
COMM
TOP VIEW
(BUMP SIDE DOWN)
Not to Scale
05546-
003
BUMP 1
INDICATOR
VPOS
RFIN
1
2
4
3
Figure 3. 4-Ball WLCSP Pin Configuration
Table 3. Pin Function Descriptions
Ball No.
Mnemonic
Description
1 VRMS
Output Pin. Rail-to-rail voltage output with limited current drive capability. The output has an internal 1 k
series resistance. High resistive loads are recommended to preserve output swing.
2
COMM
Device Ground Pin.
3
RFIN
Signal Input Pin. Internally ac-coupled after internal termination resistance. Nominal 50 input impedance.
4
VPOS
Supply Voltage Pin. Operational range 2.7 V to 5.5 V.
ADL5500
Rev. A | Page 9 of 24
TYPICAL PERFORMANCE CHARACTERISTICS
T
A
= 25°C, V
S
= 5.0 V, C
FLT
= 10 nF, light condition 600 LUX, Colors: black = +25°C, blue = -40°C, red = +85°C, unless otherwise noted.
10
0.03
25
15
05546-
004
INPUT (dBm)
OUTPUT (
V
)
0.1
1
20
15
10
5
0
5
10
100MHz
450MHz
900MHz
1900MHz
2350MHz
2700MHz
3900MHz
Figure 4. Output vs. Input Level, Frequencies 100 MHz, 450 MHz, 900 MHz,
1900 MHz, 2350 MHz, 2700 MHz, and 3900 MHz, Supply 5.0 V
5.0
0
0
1.4
INPUT (V rms)
OU
T
P
U
T
(
V
)
4.5
4.0
3.5
3.0
2.5
2.0
1.5
1.0
0.5
0.2
0.4
0.6
0.8
1.0
1.2
05
54
6-
0
05
100MHz
450MHz
900MHz
1900MHz
2350MHz
2700MHz
3900MHz
Figure 5. Output vs. Input Level (Linear Scale), Frequencies 100 MHz, 450 MHz,
900 MHz,1900 MHz, 2350 MHz, 2700 MHz, and 3900 MHz, Supply 5.0 V
11
0
0
0.9
05546-006
INPUT (V rms)
S
UP
P
L
Y
CURRE
NT (mA)
1
7
0.1
0.2
0.3
0.4
0.5
0.6
0.8
0.7
6
5
9
8
4
3
2
10
3.0V
5.0V
Figure 6. Supply Current vs. Input Level, Supplies 3.0 V and 5.0 V,
Temperatures -40°C, +25°C, and +85°C
3
3
25
15
05546-007
INPUT (dBm)
ERROR (
d
B)
2
1
0
1
2
20
15
10
5
0
5
10
100MHz
450MHz
900MHz
1900MHz
2350MHz
2700MHz
3900MHz
Figure 7. Linearity Error vs. Input Level, Frequencies 100 MHz, 450 MHz,
900 MHz, 1900 MHz, 2350 MHz, 2700 MHz, and 3900 MHz, Supply 5.0 V
10
0.03
25
15
05546-008
INPUT (dBm)
OUTPUT (V)
0.1
1
20
15
10
5
0
5
10
2.7V
5.0V
5.5V
3.0V
Figure 8. Output vs. Input Level,
Supply 2.7 V, 3.0 V, 5.0 V, and 5.5 V, Frequency 900 MHz
25
5
0
6
05546-009
FREQUENCY (GHz)
RE
TURN LOS
S
(dB)
20
15
10
1
2
3
4
5
Figure 9. Return Loss vs. Frequency
ADL5500
Rev. A | Page 10 of 24
3
3
25
15
05546-
010
INPUT (dBm)
E
RROR (d
B)
2
1
0
1
2
20
15
10
5
0
5
10
Figure 10. Temperature Drift Distributions for 55 Devices at -40°C, +25°C,
and +85°C vs. +25°C Linear Reference, Frequency 450 MHz, Supply 5.0 V
3
3
25
15
05546-
0
1
1
INPUT (dBm)
E
RROR (d
B)
2
1
0
1
2
20
15
10
5
0
5
10
Figure 11. Temperature Drift Distributions for 55 Devices at -40°C, +25°C,
and +85°C vs. +25°C Linear Reference, Frequency 900 MHz, Supply 5.0 V
3
3
25
15
05546-
012
INPUT (dBm)
ERROR (d
B)
2
1
0
1
2
20
15
10
5
0
5
10
Figure 12. Temperature Drift Distributions for 55 Devices at -40°C, +25°C,
and +85°C vs. +25°C Linear Reference, Frequency 1900 MHz, Supply 5.0 V
3
3
25
15
05546-
013
INPUT (dBm)
E
RROR (d
B)
2
1
0
1
2
20
15
10
5
0
5
10
Figure 13. Temperature Drift Distributions for 55 Devices at -40°C, +25°C,
and +85°C vs. +25°C Linear Reference, Frequency 2350 MHz, Supply 5.0 V
3
3
25
15
05546-
014
INPUT (dBm)
E
RROR (d
B)
2
1
0
1
2
20
15
10
5
0
5
10
Figure 14. Temperature Drift Distributions for 55 Devices at -40°C, +25°C,
and +85°C vs. +25°C Linear Reference, Frequency 2700 MHz, Supply 5.0 V
3
3
25
15
05546-
015
INPUT (dBm)
E
RROR (d
B)
2
1
0
1
2
20
15
10
5
0
5
10
Figure 15. Temperature Drift Distributions for 55 Devices at -40°C, +25°C,
and +85°C vs. +25°C Linear Reference, Frequency 3900 MHz, Supply 5.0 V
ADL5500
Rev. A | Page 11 of 24
3
3
25
15
05546-
016
INPUT (dBm)
E
RROR (d
B)
2
1
0
1
2
20
15
10
5
0
5
10
Figure 16. Output Delta from +25°C Output Voltage for 55 Devices
at -40°C and +85°C, Frequency 450 MHz, Supply 5.0 V
3
3
25
15
05546-
017
INPUT (dBm)
E
RROR (d
B)
2
1
0
1
2
20
15
10
5
0
5
10
Figure 17. Output Delta from +25°C Output Voltage for 55 Devices
at -40°C and +85°C, Frequency 900 MHz, Supply 5.0 V
3
3
25
15
05546-
018
INPUT (dBm)
E
RROR (d
B)
2
1
0
1
2
20
15
10
5
0
5
10
Figure 18. Output Delta from +25°C Output Voltage for 55 Devices
at -40°C and +85°C, Frequency 1900 MHz, Supply 5.0 V
3
3
25
15
05546-
019
INPUT (dBm)
E
RROR (d
B)
2
1
0
1
2
20
15
10
5
0
5
10
Figure 19. Output Delta from +25°C Output Voltage for 55 Devices
at -40°C and +85°C, Frequency 2350 MHz, Supply 5.0 V
3
3
25
15
05546-
020
INPUT (dBm)
E
RROR (d
B)
2
1
0
1
2
20
15
10
5
0
5
10
Figure 20. Output Delta from +25°C Output Voltage for 55 Devices
at -40°C and +85°C, Frequency 2700 MHz, Supply 5.0 V
3
3
25
15
05546-
021
INPUT (dBm)
ERROR (
d
B)
2
1
0
1
2
20
15
10
5
0
5
10
Figure 21. Output Delta from +25°C Output Voltage for 55 Devices
at -40°C and +85°C, Frequency 3900 MHz, Supply 5.0 V
ADL5500
Rev. A | Page 12 of 24
10
0.03
25
15
05546-
022
INPUT (dBm)
OU
TP
U
T
(V
)
0.1
1
20
15
10
5
0
5
10
CW
QPSK, 4.8dB CF
8PSK, 4.8dB CF
16QAM, 6.3dB CF
64QAM, 7.4dB CF
Figure 22. Output vs. Input Level with Different Waveforms, 10 MHz Signal
BW for All Modulated Signals, Supply 5.0 V, Frequency 1900 MHz
3.0
3.0
25
10
05546-
023
INPUT (dBm)
ERRO
R (dB)
2.5
2.0
1.5
1.0
0.5
0
0.5
1.0
1.5
2.0
2.5
20
15
10
5
0
5
CW
BPSK, 11dB CF
QPSK, 11dB CF
16QAM, 12dB CF
64QAM, 11dB CF
Figure 23. Error from CW Linear Reference vs. Input Level for Various
802.16 OFDM Waveforms at 2.35 GHz, 10 MHz Signal BW and
256 Subcarriers for All Modulated Signals, Supply 5.0 V
3.0
3.0
25
10
05546-
024
INPUT (dBm)
ERRO
R (dB)
2.0
1.0
0
1.0
2.0
20
15
10
5
0
5
CW
12.2kbps, DPCCH (5.46dB, 15ksps) +
DPDCH (0dB, 60ksps), 3.4dB CF
64kbps, DPCCH (9.54dB, 15ksps) +
DPDCH (0dB, 240ksps), 3.4dB CF
144kbps, DPCCH (11.48dB, 15ksps) +
DPDCH (0dB, 480ksps), 3.3dB CF
384kbps, DPCCH (11.48dB, 15ksps) +
DPDCH (0dB, 960ksps), 3.3dB CF
768kbps, DPCCH (11.48dB, 15ksps) +
DPDCH1 + 2 (0dB, 960ksps), 5.8dB CF
Figure 24. Error from CW Linear Reference vs. Input with Various
WCDMA Up Link Waveforms at 1900 MHz
3.0
3.0
25
10
05546-
025
INPUT (dBm)
ERRO
R (dB)
2.5
2.0
1.5
1.0
0.5
0
0.5
1.0
1.5
2.0
2.5
20
15
10
5
0
5
CW
QPSK, 4.8dB CF
8PSK, 4.8dB CF
16QAM, 6.3dB CF
64QAM, 7.4dB CF
Figure 25. Error from CW Linear Reference vs. Input with Different Waveforms,
10 MHz Signal BW for All Modulated Signals, Supply 5.0 V, Frequency 1900 MHz
3.0
3.0
25
10
05546-
026
INPUT (dBm)
ERRO
R (dB)
2.5
2.0
1.5
1.0
0.5
0
0.5
1.0
1.5
2.0
2.5
20
15
10
5
0
5
CW
BPSK, 11dB CF
QPSK, 11dB CF
16QAM, 12dB CF
64QAM, 11dB CF
Figure 26. Error from CW Linear Reference vs. Input Level for Various
802.16 OFDM Waveforms at 3.5 GHz, 10 MHz Signal BW and
256 Subcarriers for All Modulated Signals, Supply 5.0 V
3.0
3.0
25
10
05546-
027
INPUT (dBm)
ERRO
R (dB)
2.0
1.0
0
1.0
2.0
20
15
10
5
0
5
CW
PICH, 4.7dB CF
PICH + FCH (9.6kbps), 4.8dB CF
PICH + FCH (9.6kbps) +
DCCH, 6.3dB CF
PICH + FCH (9.6kbps) +
SCH (153.6kbps), 6.7dB CF
PICH + FCH (9.6kbps) +
DCCH + SCH (153.6kbps), 7.6dB CF
Figure 27. Error from CW Linear Reference vs. Input with Various
CDMA2000 Reverse Link Waveforms at 900 MHz
ADL5500
Rev. A | Page 13 of 24
COMM
VRMS
RFIN
VPOS
2
4
3
1
ADL5500
HP8648B
SIGNAL
GENERATOR
HPE3631A
POWER SUPPLY
TEK P6204
FET PROBE
TEK TDS784C
SCOPE
C4
C1
0.1
F
05546-028
C2
100pF
Figure 28. Hardware Configuration for Output
Response to Modulated Pulse Input
05546-
029
VRMS
500mV PER
VERTICAL
DIVISION
400
s PER
HORIZONTAL
DIVISION
900MHz
PULSED RFIN
400mV rms
RF INPUT
250mV rms
160mV rms
70mV rms
Figure 29. Output Response to Modulated Pulse Input for Various RF Input
Levels, Supply 3 V, Modulation Frequency 900 MHz, No Filter Capacitor
05546-
030
VRMS
500mV PER
VERTICAL
DIVISION
400
s PER
HORIZONTAL
DIVISION
900MHz
PULSED RFIN
400mV rms
RF INPUT
250mV rms
160mV rms
70mV rms
Figure 30. Output Response to Modulated Pulse Input for Various RF Input
Levels, Supply 3 V, Modulation Frequency 900 MHz, 0.01 F Filter Capacitor
COMM
VRMS
RFIN
VPOS
2
4
3
1
ADL5500
HP8648B
SIGNAL
GENERATOR
HP8110A
PULSE
GENERATOR
TEK P6204
FET PROBE
TEK TDS784C
SCOPE
C4
C2
100pF
C1
0.1
F
05546-031
732
50
AD811
Figure 31. Hardware Configuration for Output Response to
Power Supply Gating Measurements
05546-
032
VRMS
500mV PER
VERTICAL
DIVISION
200
s PER
HORIZONTAL
DIVISION
VPOS
400mV rms
RF INPUT
250mV rms
160mV rms
70mV rms
Figure 32. Output Response to Gating on Power Supply for Various RF Input
Levels, Supply 3 V, Modulation Frequency 900 MHz, 0.01 F Filter Capacitor
ADL5500
Rev. A | Page 14 of 24
CIRCUIT DESCRIPTION
The ADL5500 is an rms-responding (mean power) detector that
provides an approach to the exact measurement of RF power
that is independent of waveform. It achieves this function by
using a proprietary technique in which the outputs of two
identical squaring cells are balanced by the action of a high-gain
error amplifier.
The signal to be measured is applied to the input of the first
squaring cell through the input matching network. The input is
matched to offer a broadband 50 input impedance from
100 MHz to 6 GHz. The input matching network has a high-pass
corner frequency of approximately 90 MHz.
The ADL5500 responds to the voltage, V
IN
, at its input by
squaring this voltage to generate a current proportional to V
IN
2
.
This current is applied to an internal load resistor in parallel
with a capacitor, followed by a low-pass filter, which extracts the
mean of V
IN
2
. Although essentially voltage responding, the
associated input impedance calibrates this port in terms of
equivalent power. Therefore, 1 mW corresponds to a voltage
input of 224 mV rms referenced to 50 . Because both the
squaring cell input impedance and the input matching network
are frequency dependent, the conversion gain is a function of
signal frequency.
The voltage across the low-pass filter, whose frequency can be
arbitrarily low, is applied to one input of an error-sensing
amplifier. A second identical voltage-squaring cell is used to
close a negative feedback loop around this error amplifier. This
second cell is driven by a fraction of the quasi-dc output voltage
of the ADL5500. When the voltage at the input of the second
squaring cell is equal to the rms value of V
IN
, the loop is in a
stable state, and the output then represents the rms value of the
input.
By completing the feedback path through a second squaring
cell, identical to the one receiving the signal to be measured,
several benefits arise. First, scaling effects in these cells cancel;
therefore, the overall calibration can be accurate, even though
the open-loop response of the squaring cells taken separately
need not be. Note that in implementing rms-dc conversion, no
reference voltage enters into the closed-loop scaling. Second,
the tracking in the responses of the dual cells remains very close
over temperature, leading to excellent stability of calibration.
The squaring cells have very wide bandwidth with an intrinsic
response from dc to microwave. However, the dynamic range of
such a system is small due in part to the much larger dynamic
range at the output of the squaring cells. There are practical
limitations to the accuracy of sensing very small error signals at
the bottom end of the dynamic range, arising from small random
offsets that limit the attainable accuracy at small inputs.
On the other hand, the squaring cells in the ADL5500 have a
Class-AB aspect; the peak input is not limited by its quiescent
bias condition but is determined mainly by the eventual loss of
square-law conformance. Consequently, the top end of their
response range occurs at a large input level (approximately
700 mV rms) while preserving a reasonably accurate square-law
response. The maximum usable range is, in practice, limited by
the output swing. The rail-to-rail output stage can swing from a
few millivolts above ground to within 100 mV below the supply.
An example of the output induced limit, given a conversion gain
of 6.4 V/V rms at 900 MHz and assuming a maximum output of
2.9 V with a 3 V supply, has a maximum input of 2.9 V rms/6.4
or 450 mV rms.
FILTERING
An important aspect of rms-dc conversion is the need for
averaging (the function is root-mean-square). The on-chip
averaging in the square domain has a corner frequency of
approximately 150 kHz and is sufficient for common
modulation signals, such as CDMA, WCDMA, and QPSK-
/QAM-based OFDM (for example, WLAN and WiMAX). It
ensures the accuracy of rms measurement for these signals;
however, it leaves significant ripple on the output. To reduce
this ripple, an external shunt capacitor can be used at the output
to form a low-pass filter with the on-chip 1 k resistance (see
the Selecting the Output Low-Pass Filter Network section).
ADL5500
Rev. A | Page 15 of 24
APPLICATIONS
BASIC CONNECTIONS
Figure 33 shows the basic connections for the ADL5500. The
device is powered by a single supply of between 2.7 V and 5.5 V
with a quiescent current of 1.0 mA. The VPOS pin is decoupled
using 100 pF and 0.1 F capacitors.
The ADL5500 RF input does not require external termination
components because it is internally matched for an overall
broadband input impedance of 50 .
COMM
VRMS
RFIN
VPOS
2
4
3
1
ADL5500
CFLT
05546-033
VRMS
RFIN
100pF
0.1
F
+V
S
2.7V TO 5.5V
Figure 33. Basic Connections for ADL5500
OUTPUT SWING
At 900 MHz, the output voltage is nominally 6.4 times the input
rms voltage (a conversion gain of 6.4 V/V rms). The output
voltage swings from near ground to 4.9 V on a 5.0 V supply.
Figure 34 shows the output swing of the ADL5500 to a CW
input for various supply voltages. It is clear from Figure 34 that
operating the device at lower supply voltages reduces dynamic
range as the output headroom decreases.
10
0.03
25
15
05546-008
INPUT (dBm)
OUT
P
UT
(V)
0.1
1
20
15
10
5
0
5
10
2.7V
5.0V
5.5V
3.0V
Figure 34. Output Swing for Supply Voltages of 2.7 V, 3.0 V, 5.0 V, and 5.5 V
LINEARITY
Because the ADL5500 is a linear-responding device, plots of
output voltage vs. input voltage result in a straight line. It is
more useful to plot the error on a logarithmic scale, as shown in
Figure 35. The deviation of the plot for the ideal straight-line
characteristic is caused by output clipping at the high end and
by signal offsets at the low end. However, it should be noted that
offsets at the low end can be either positive or negative; therefore,
this plot could also trend upwards at the low end. Figure 10
through Figure 15 show error distributions for a large
population of devices.
3
3
25
15
05546-
007
INPUT (dBm)
ERRO
R (dB)
2
1
0
1
2
20
15
10
5
0
5
10
100MHz
450MHz
900MHz
1900MHz
2350MHz
2700MHz
3900MHz
Figure 35. Representative Unit, Error in dB vs. Input Level, V
S
= 5.0 V
It is also apparent in Figure 35 that the error plot tends to shift
to the right with increasing frequency. The squaring cell has an
input impedance that decreases with frequency. The matching
network compensates for the change and maintains the input
impedance at a nominal 50 . The result is a decrease in the
actual voltage across the squaring cell as the frequency
increases, reducing the conversion gain. Similarly, conversion
gain is less at frequencies near 100 MHz because of the small
on-chip coupling capacitor.
ADL5500
Rev. A | Page 16 of 24
INPUT COUPLING USING A SERIES RESISTOR
Figure 36 shows a technique for coupling the input signal into
the ADL5500 that can be applicable where the input signal is
much larger than the input range of the ADL5500. A series
resistor combines with the input impedance of the ADL5500 to
attenuate the input signal. Because this series resistor forms a
divider with the frequency dependent input impedance, the
apparent gain changes greatly with frequency. However, this
method has the advantage of very little power being tapped off
in RF power transmission applications. If the resistor is large
compared to the transmission line's impedance, the VSWR of
the system is relatively unaffected.
ADL5500
RFIN
RFIN
05546-
036
R
SERIES
Figure 36. Attenuating the Input Signal
MULTIPLE RF INPUTS
Figure 37 shows a technique for combining multiple RF input
signals to the ADL5500. Some applications can share a single
detector for multiple bands. Three 16.5 resistors in a T-network
combine the three 50 terminations (including the ADL5500).
The broadband resistive combiner ensures each port of the
T-network sees a 50 termination. Because there is only 6 dB
of isolation from one port of the combiner to the other ports,
only one band should be active at a time.
ADL5500
RFIN
BAND 1
50
BAND 2
DIRECTIONAL
COUPLER
16.5
05546-
051
50
16.5
16.5
DIRECTIONAL
COUPLER
Figure 37. Combining Multiple RF Input Signals
SELECTING THE OUTPUT LOW-PASS FILTER
NETWORK
The ADL5500's internal filter capacitor provides averaging in
the square domain but leaves some residual ac on the output.
Signals with high peak-to-average ratios, such as W-CDMA
or CDMA2000, can produce ac-residual levels on the ADL5500
dc output. To reduce the effects of these low frequency
components in the waveforms, some additional filtering is
required.
The output of the ADL5500 can be filtered by placing a
capacitor between VRMS (Pin 1) and ground. The combination
of the on-chip 1 k output series resistance and the external
shunt capacitor forms a low-pass filter to reduce the residual ac.
Table 4 shows the effect of several capacitor values for various
communications standards with high peak-to-average ratios
along with the residual ripple at the output, in peak-to-peak and
rms volts. Note that large load capacitances increase the turn-on
and pulse response times (see Figure 29 and Figure 30).
Table 4. Waveform and Output Filter Effects on Residual AC
Output
Residual
AC
Waveform C
FILT
V dc
mV p-p
mV rms
64QAM
0.01 F
0.5
7.0
1.4
(7.4 dB CF)
1.0
7.4
1.5
2.0
7.6
1.6
0.1 F
0.5
6.7
1.4
1.0
7.2
1.5
2.0
7.4
1.5
W-CDMA RL
0.01 F
0.5
10
1.7
(3.4 dB CF)
1.0
16
2.4
2.0
45
5.6
0.1 F
0.5
7
1.5
1.0
9
1.6
2.0
14
2.3
CDMA2000 UL
0.01 F
0.5
46
6
(6.7 dB CF)
1.0
85
13
2.0
191
27
0.1 F
0.5
17
3
1.0
31
5
2.0
68
9
POWER CONSUMPTION AND POWER-ON/-OFF
RESPONSE
The quiescent current consumption of the ADL5500 varies with
the size of the input signal from approximately 1 mA for no
signal up to 6 mA at an input level of 0.7 V rms (10 dBm, re
50 ). If the input is driven beyond this point, the supply
current increases sharply (as shown in Figure 6). There is little
variation in quiescent current with power supply voltage.
The ADL5500 can be disabled by simply removing the power to
the device. Figure 32 shows a plot of the output response to the
supply being turned on (that is, VPOS is pulsed) with an output
shunt capacitor of 0.01 F. Again, the turn-on time is influenced
strongly by the size of the output shunt capacitor.
To improve the falling edge of the supply gating response and
the pulse response, a resistor can be placed in parallel with the
output shunt capacitor. The added resistance helps discharge
the capacitor. Although this method reduces the power-off
time, the added load resistor also attenuates the output (see the
Output Drive Capability and Buffering section).
ADL5500
Rev. A | Page 17 of 24
OUTPUT DRIVE CAPABILITY AND BUFFERING
The ADL5500 is capable of sourcing an output current of
approximately 3 mA. The output current is sourced through the
on-chip 1 k series resistor; therefore, any load resistor forms a
voltage divider with this on-chip resistance. It is recommended
that the ADL5500 drive high resistive loads to preserve output
swing (preferably >100 k). If an application requires driving
a low resistance load, a simple buffering circuit can be used,
as shown in Figure 40. Similar circuits can be used to increase
or decrease the nominal conversion gain (see Figure 38 and
Figure 39). In Figure 39, the AD8031 buffers a resistive divider
to give half of the slope. In Figure 38, the op amp's gain of two
doubles the slope. Using other resistor values, the slope can be
changed to an arbitrary value. The AD8031 rail-to-rail op amp,
used in these examples, can swing from 50 mV to 4.95 V on a
single 5 V supply and operates at supply voltages down to 2.7 V.
If high output current is required (>10 mA), the AD8051, which
also has rail-to- rail capability, can be used down to a supply
voltage of 3 V. It can deliver up to 45 mA of output current.
100pF
0.1
F
0.01
F
ADL5500
VRMS
VPOS
COMM
5k
5k
5V
12.8V/V rms
AD8031
05546-
037
Figure 38. Output Buffering Options, Slope of 12.8 V/V rms at 900 MHz
100pF
0.1
F
0.01
F
ADL5500
VRMS
VPOS
COMM
5V
3.2V/V rms
AD8031
5k
4k
05546-038
Figure 39. Output Buffering Options, Slope of 3.2 V/V rms at 900 MHz
100pF
0.1
F
0.01
F
ADL5500
VRMS
VPOS
COMM
5V
6.4V/V rms
AD8031
05546-039
Figure 40. Output Buffering Options, Slope of 6.4 V/V rms at 900 MHz
VRMS OUTPUT OFFSET
The ADL5500 has a ±1 dB error detection range of about 30 dB,
as shown in Figure 10 to Figure 15. The error is referred to the
best fit line defined in the linear region of the output response.
Below an input power of -20 dBm, the response is no longer
linear and begins to lose accuracy. In addition, depending on
the supply voltage, saturation of the output limits the detection
accuracy above 10 dBm. Calibration points should be chosen in
the linear region, avoiding the nonlinear ranges at the high and
low extremes.
10
0.01
40
10
05546-040
INPUT (dBm)
OUTPUT (V)
0.1
1
35
30
25
20
15
10
5
0
5
Figure 41. Output vs. Input Level Distribution of 55 Devices,
Frequency 900 MHz, Supply 3.0 V
Figure 41 shows the distribution of the output response vs.
the input power for multiple devices. The ADL5500 loses
accuracy at low input powers as the output response begins to
fan out. As the input power is reduced, the spread of the output
response increases along with the error. Although some devices
follow the ideal linear response at very low input powers, not
all devices continue the ideal linear regression to a near 0 V
y-intercept. Some devices exhibit output responses that rapidly
decrease and some flatten out. With no RF signal applied,
the ADL5500 has a typical output offset of 40 mV (with a
maximum of 150 mV).
ADL5500
Rev. A | Page 18 of 24
DEVICE CALIBRATION AND ERROR CALCULATION
Because slope and intercept vary from device to device, board-
level calibration must be performed to achieve high accuracy. In
general, calibration is performed by applying two input power
levels to the ADL5500 and measuring the corresponding output
voltages. The calibration points are generally chosen to be
within the linear operating range of the device. The best fit line
is characterized by calculating the slope and intercept using the
following equations:
Slope = (V
RMS2
- V
RMS1
)/(V
IN2
- V
IN1
) (1)
Intercept = V
RMS1
- (Slope × V
IN1
) (2)
where:
V
IN
is the rms input voltage to RFIN.
V
RMS
is the voltage output at VRMS.
Once slope and intercept have been calculated, an equation can
be written that allows calculation of an (unknown) input power
based on the measured output voltage.
V
IN
= (V
RMS
- Intercept)/Slope (3)
For an ideal (known) input power, the law conformance error of
the measured data can be calculated as
ERROR (dB) =
20 × log [(V
RMS, MEASURED
- Intercept)/(Slope × V
IN, IDEAL
)] (4)
Figure 42 includes a plot of the error at 25°C, the temperature at
which the ADL5500 is calibrated. Note that the error is not zero.
This is because the ADL5500 does not perfectly follow the ideal
linear equation, even within its operating region. The error at
the calibration points is, however, equal to zero by definition.
3
3
25
15
05546-052
INPUT (dBm)
ERROR (dB)
2
1
0
1
2
20
15
10
5
0
5
10
40°C
+25°C
+85°C
Figure 42. Error from Linear Reference vs. Input at -40°C, +25°C, and +85°C
vs. +25°C Linear Reference, Frequency 900 MHz, Supply 5.0 V
Figure 42 also includes error plots for the output voltage at
-40°C and +85°C. These error plots are calculated using the
slope and intercept at +25°C. This is consistent with calibration
in a mass-production environment where calibration at
temperature is not practical.
CALIBRATION FOR IMPROVED ACCURACY
Another way of presenting the error function of the ADL5500 is
shown in Figure 43. In this case, the dB error at hot and cold
temperatures is calculated with respect to the transfer function
at ambient. This is a key difference in comparison to the
previous plots. Up to now, the errors have been calculated with
respect to the ideal linear transfer function at ambient. When
this alternative technique is used, the error at ambient becomes
equal to 0 by definition (see Figure 43).
This plot is a useful tool for estimating temperature drift at a
particular power level with respect to the (nonideal) response at
ambient. The linearity and dynamic range tend to be improved
artificially with this type of plot because the ADL5500 does not
perfectly follow the ideal linear equation (especially outside of
its linear operating range). Achieving this level of accuracy in
an end application requires calibration at multiple points in the
device's operating range.
In some applications, very high accuracy is required at just one
power level or over a reduced input range. For example, in a
wireless transmitter, the accuracy of the high power amplifier
(HPA) is most critical at or close to full power. The ADL5500
offers a tight error distribution in the high input power range,
as shown in Figure 43. The high accuracy range, centered
around +3 dBm at 900 MHz, offers 8.5 dB of ±0.1 dB detection
error over temperature. Multiple point calibration at ambient
temperature in the reduced range offers precise power
measurement with near 0 dB error from -40°C to +85°C.
3
3
25
15
05546-053
INPUT (dBm)
ERROR (dB)
2
1
0
1
2
20
15
10
5
0
5
10
40°C
+85°C
+25°C
Figure 43. Error from +25°C Output Voltage at -40°C, +25°C, and +85°C
After Ambient Normalization, Frequency 900 MHz, Supply 5.0 V
ADL5500
Rev. A | Page 19 of 24
The high accuracy range center varies over frequency. At
900 MHz, the region is centered at approximately 3 dBm. At
higher frequencies, the high accuracy range is centered at
higher input powers (see Figure 16 to Figure 21).
DRIFT OVER A REDUCED TEMPERATURE RANGE
Figure 44 shows the error over temperature for a 1.9 GHz input
signal. Error due to drift over temperature consistently remains
within ±0.25 dB and only begins to exceed this limit when the
ambient temperature goes above +50°C and below -10°C. For
all frequencies using a reduced temperature range, higher
measurement accuracy is achievable.
1.00
1.00
20
15
05546-
041
INPUT (dBm)
ERRO
R (dB)
0.75
0.50
0.25
0
0.25
0.50
0.75
15
10
5
0
5
10
+85°C
+70°C
+50°C
+30°C
+25°C
+15°C
0°C
10°C
25°C
40°C
Figure 44. Typical Drift at 1.9 GHz for Various Temperatures
OPERATION ABOVE 4.0 GHz
The ADL5500 works at frequencies above 4.0 GHz, but exhibits
slightly higher output voltage temperature drift. Figure 45 and
Figure 46 show the error distributions of six devices at 5.0 GHz
and 6.0 GHz over temperature. Although the temperature drift
is larger than at lower frequencies, the error distributions at
each temperature remain tight throughout the central linear
region. Due to the repeatability of the drift from part-to-part,
compensation can be applied to reduce the effects of
temperature drift.
3
3
25
15
05546-
042
INPUT (dBm)
ERRO
R (dB)
2
1
0
1
2
20
15
10
5
0
5
10
Figure 45. Temperature Drift Distributions for Six Devices at -40°C, +25°C,
and +85°C After Ambient Normalization, Frequency 5.0 GHz, Supply 5.0 V
3
3
25
15
05546-
043
INPUT (dBm)
ERRO
R (dB)
2
1
0
1
2
20
15
10
5
0
5
10
Figure 46. Temperature Drift Distributions for Six Devices at -40°C, +25°C,
and +85°C After Ambient Normalization, Frequency 6.0 GHz, Supply 5.0 V
DEVICE HANDLING
The wafer-level chip scale package consists of solder bumps
connected to the active side of the die. The part is lead-free with
95.5% tin, 4.0% silver, and 0.5% copper solder bump composition.
The WLCSP can be mounted on printed circuit boards using
standard surface-mount assembly techniques; however, caution
should be taken to avoid damaging the die. See the
AN-617
Application Note for additional information. WLCSP devices
are bumped die; therefore, the exposed die can be sensitive to
light, which can influence specified limits. Lighting in excess of
600 LUX can degrade performance.
ADL5500
Rev. A | Page 20 of 24
EVALUATION BOARD
Figure 48 shows the schematic of the ADL5500 evaluation
board. The layout and silkscreen of the evaluation board layers
are shown in Figure 49 to Figure 52. The board is powered by a
single supply in the 2.7 V to 5.5 V range. The power supply is
decoupled by 100 pF and 0.01 F capacitors. Table 5 details the
various configuration options of the evaluation board.
Problems caused by impedance mismatch can arise using the
evaluation board to examine the ADL5500 performance. One
way to reduce these problems is to put a coaxial 3 dB attenuator
on the RFIN SMA connector. Mismatches at the source, cable,
and cable interconnection, as well as those occurring on the
evaluation board, can cause these problems.
A simple (and common) example of such a problem is triple
travel due to mismatch at both the source and the evaluation
board. Here the signal from the source reaches the evaluation
board and mismatch causes a reflection. When that reflection
reaches the source mismatch, it causes a new reflection, which
travels back to the evaluation board, adding to the original
signal incident at the board. The resultant voltage varies with
both cable length and frequency dependence on the relative
phase of the initial and reflected signals. Placing the 3 dB pad at
the input of the board improves the match at the board and thus
reduces the sensitivity to mismatches at the source. When such
precautions are taken, measurements are less sensitive to cable
length and other fixture issues. In an actual application when
the distance between ADL5500 and source is short and well-
defined, this 3 dB attenuator is not needed.
Land Pattern and Soldering Information
Figure 47 shows the land pattern used on the ADL5500
evaluation board. Pad diameters of 0.28 mm are used with a
solder paste mask opening of 0.38 mm. For the RF input trace, a
trace width of 0.30 mm is used, which corresponds to a 50
characteristic impedance for the dielectric material being used
(FR4). All traces going to the pads are tapered down to 0.15 mm.
For the RFIN line, the length of the tapered section is 0.20 mm.
0.28 mm
0.50 mm
0.15 mm
0.30 mm
(50
)
0.15 mm
0.50 mm
0.38 mm
(PASTE MASK OPENING)
RFIN
VPOS
VRMS
COMM
0.20 mm
GROUND
PLANE
05546-054
Figure 47. Land Pattern Used on the ADL5500 Evaluation Board
COMM
VRMS
RFIN
VPOS
2
4
3
1
ADL5500
C4
10nF
R8
(OPEN)
R6
(OPEN)
05546-044
VRMS
RFIN
VPOS
C1
100pF
C2
0.1
F
TO EDGE
CONNECTOR
R3
0
Figure 48. Evaluation Board Schematic
Table 5. Evaluation Board Configuration Options
Component
Description
Default Condition
VPOS, GND
Ground and Supply Vector Pins.
Not Applicable
C1, C2
Power Supply Decoupling. The nominal supply decoupling of 0.01 F and 100 pF.
C1 = 0.01 F (Size 0402)
C2 = 100 pF (Size 0402)
R3, R8, C4
Output Filtering. The combination of the internal 1 k output resistance and C4 produce
a low-pass filter to reduce output ripple. The output can also be scaled down using the
resistor divider pads, R3 and R8. In addition, resistors and capacitors can be placed in C4 and
R8 to load test VRMS.
R3 = 0 (Size 0402)
R8 = Open (Size 0402)
C4 = 10 nF (Size 0402)
R6
Alternate Interface. R6 allows VOUT to be accessible from the edge connector, which is only
used for characterization.
R6 = Open (Size 0402)
ADL5500
Rev. A | Page 21 of 24
05546-045
Figure 49. Layout of Component Side (WLCSP)
05546-046
Figure 50. Layout of Circuit Side (WLCSP)
05546-047
Figure 51. Silkscreen of Component Side (WLCSP)
05546-048
Figure 52. Silkscreen of Circuit Side (WLCSP)
ADL5500
Rev. A | Page 22 of 24
OUTLINE DIMENSIONS
SEATING
PLANE
0.50 BSC
BALL PITCH
0.030 NOM
COPLANARITY
1.010
0.960 SQ
0.910
0.270
0.240
0.210
0.345
0.295
0.245
0.381
0.356
0.331
0.675
0.596
0.516
BOTTOM VIEW
(BALL SIDE UP)
TOP VIEW
(BALL SIDE DOWN)
A
1
2
B
A1 BALL
CORNER
11
11
0
5
-
0
Figure 53. 4-Ball Wafer-Level Chip Scale Package [WLCSP]
(CB-4)
Dimensions shown in millimeters
ORDERING GUIDE
Model
Temperature Range
Package Description
Package Option
Branding
Ordering
Quantity
ADL5500ACBZ-P7
1
40°C to +85°C
4-Ball WLCSP, 7" Pocket Tape and Reel
CB-4
Q06
3,000
ADL5500ACBZ-P2
1
40°C to +85°C
4-Ball WLCSP, 7" Pocket Tape and Reel
CB-4
Q06
250
ADL5500-EVALZ
1
Evaluation
Board
1
Z = Pb-free part.
ADL5500
Rev. A | Page 23 of 24
NOTES
ADL5500
Rev. A | Page 24 of 24
NOTES
©2006 Analog Devices, Inc. All rights reserved. Trademarks and
registered trademarks are the property of their respective owners.
D0554602/06(A)
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