19-2601; Rev 1; 2/04
IF Digitally Controlled Variable-Gain Amplifier
General Description
The MAX2027 high-performance, digitally controlled
variable-gain amplifier is designed for use from 50MHz
to 400MHz.
The device integrates a digitally controlled attenuator
and a high-linearity IF amplifier in one package.
Targeted for IF signal chains to adjust gain either
dynamically or as a one-time channel gain setting, the
MAX2027 is ideal for applications requiring high perfor-
mance. The attenuator provides 23dB of attenuation
range with ±0.05dB state-to-state accuracy.
The MAX2027 is available in a thermally enhanced 20-
pin TSSOP-EP package and operates over the -40°C to
+85°C temperature range.
♦
50MHz to 400MHz Frequency Range
♦
Variable Gain: -8dB to +15dB
♦
Output IP3: 35dBm (at All Gain Settings)
♦
Noise Figure: 4.7dB at Maximum Gain
♦
Digitally Controlled Gain with 1dB Resolution and
±0.05dB State-to-State Accuracy
Features
MAX2027
Ordering Information
PART
MAX2027EUP-T
TEMP RANGE
-40°C to +85°C
PIN-PACKAGE
20 TSSOP-EP*
*EP
= exposed pad.
Applications
Cellular Base Stations
Receiver Gain Control
Transmitter Gain Control
Broadband Systems
Automatic Test Equipment
Terrestrial Links
V
CC
RF_IN
GND
GND
B4
B3
B2
B1
2
3
4
5
6
7
8
9
V
CC
1
Pin Configuration/
Functional Diagram
20 GND
MAX2027
19 GND
18 ATTN
OUT
17 GND
16 GND
15 AMP
IN
ATTENUATION
LOGIC
CONTROL
AMP
BIAS
14 I
BIAS
13 I
SET
12 RF_OUT
11 V
CC
B0 10
________________________________________________________________
Maxim Integrated Products
1
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
IF Digitally Controlled Variable-Gain Amplifier
MAX2027
ABSOLUTE MAXIMUM RATINGS
All Pins Input Voltage (except AMP
IN
, I
BIAS
, and I
SET
)
to GND................................................................-0.3V to +5.5V
Input Voltage Levels (B0–B4).....................-0.3V to (V
CC
+ 0.5V)
Input Voltage Levels (AMP
IN
and I
BIAS
)................-0.3V to +1.5V
Input Voltage Levels (I
SET
) ....................................-0.3V to +1.0V
RF Input Signal .................................................................20dBm
RF Output Signal...............................................................22dBm
Continuous Power Dissipation (T
A
= +70°C)
20-Pin TSSOP-EP
(derate 21.7mW/°C above +70°C) ..................................1.7W
Operating Temperature Range ...........................-40°C to +85°C
Junction Temperature ......................................................+150°C
Storage Temperature Range .............................-65°C to +165°C
Lead Temperature (soldering, 10s) .................................+300°C
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
DC ELECTRICAL CHARACTERISTICS
(Typical application circuit, V
CC
= +4.75V to +5.25V, GND = 0V. No RF signals applied, and RF input and output ports are terminated
with 50Ω. R
1
= 825Ω, T
A
= -40°C to +85°C. Typical values are at V
CC
= +5V and T
A
= +25°C, unless otherwise noted.) (Notes 1, 2)
PARAMETER
SUPPLY
Supply Voltage
Supply Current
I
SET
Current
CONTROL INPUTS/OUTPUTS
Control Bits
Input Logic High
Input Logic Low
Input Leakage Current
-1.2
Parallel
(Note 3)
2
0.6
+1.2
5
Bits
V
V
µA
V
CC
I
CC
I
SET
4.75
5.00
60
0.9
5.25
75
V
mA
mA
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
2
_______________________________________________________________________________________
IF Digitally Controlled Variable-Gain Amplifier
AC ELECTRICAL CHARACTERISTICS
(Typical application circuit without matching, V
CC
= +4.75V to +5.25V, GND = 0V, max gain (B0 = B1 = B2 = B3 = B4 = 0), R
1
=
825Ω, P
OUT
= 5dBm, f
IN
= 50MHz, 50Ω RF system impedance. Typical values are at V
CC
= +5V and T
A
= +25°C, unless otherwise
noted.) (Notes 1, 2)
PARAMETER
Frequency Range
Gain
Noise Figure
Minimum Reverse Isolation
Output 1dB Compression Point
2nd-Order Output Intercept Point
3rd-Order Output Intercept Point
2nd Harmonic
3rd Harmonic
RF Gain-Control Range
Gain-Control Resolution
Attenuation Absolute Accuracy
Attenuation Relative Accuracy
Gain Drift Over Temperature
Compared to the ideal expected
attenuation
Between adjacent states
T
A
= -40°C to +85°C
Peak-to-peak for all settings,
F
CENTER
= 75MHz
Peak-to-peak for all settings,
F
CENTER
= 200MHz
Attenuator Switching Time
Input Return Loss
Output Return Loss
50% control to 90% RF
f
R
= 50MHz to 250MHz, all gain conditions
f
R
= 50MHz to 250MHz, all gain conditions
P
1dB
OIP2
OIP3
2f
IN
3f
IN
SYMBOL
f
R
G
NF
No attenuation
Max gain
Max gain
Max gain
f
1
+ f
2
, f
1
= 50MHz, f
2
= 51MHz, 5dBm/tone
All gain conditions, 5dBm/tone
CONDITIONS
MIN
50
15.5
4.7
22
20.6
42
34.7
-44
-68
23
1
0.15/
-0.05
±0.05
±0.1
0.1
dB
0.2
40
15
15
ns
dB
dB
TYP
MAX
400
UNITS
MHz
dB
dB
dB
dBm
dBm
dBm
dBc
dBc
dB
dB
dB
dB
dB
MAX2027
Gain Flatness Over 50MHz BW
Note 1:
Guaranteed by design and characterization.
Note 2:
All limits reflect losses of external components. Output measurements are taken at RF OUT using the typical application
circuit.
_______________________________________________________________________________________
3
IF Digitally Controlled Variable-Gain Amplifier
MAX2027
Typical Operating Characteristics
(Typical
application circuit, V
CC
= 5.0V, max gain (B0 = B1 = B2 = B3 = B4 = 0), P
OUT
= 5dBm, R
1
= 825Ω, T
A
= +25°C, unless
otherwise noted.)
SUPPLY CURRENT vs. TEMPERATURE
MAX2027 toc01
INPUT RETURN LOSS
vs. RF FREQUENCY (ALL STATES)
MAX2027 toc02
OUTPUT RETURN LOSS
vs. RF FREQUENCY (ALL STATES)
MAX2027 toc03
68
66
SUPPLY CURRENT (mA)
64
62
60
58
56
54
52
-40 -25 -10
5
20
35
50
65
80
TEMPERATURE (°C)
V
CC
= 4.75V
V
CC
= 5.25V
V
CC
= 5.0V
0
5
INPUT RETURN LOSS (dB)
10
15
20
25
30
35
50
100
150
200
250
300
350
0
5
OUTPUT RETURN LOSS (dB)
10
15
20
25
30
35
400
50
100
150
200
250
300
350
400
FREQUENCY (MHz)
FREQUENCY (MHz)
GAIN vs. RF FREQUENCY
(ALL STATES)
MAX2027 toc04
REVERSE ISOLATION vs. FREQUENCY
MAX2027 toc05
20
15
10
GAIN (dB)
5
0
-5
-10
-15
50
100
150
200
250
300
350
35
30
REVERSE ISOLATION (dB)
25
20
15
10
5
400
50
100
150
200
250
300
350
400
FREQUENCY (MHz)
FREQUENCY (MHz)
GAIN vs. FREQUENCY
MAX2027 toc06
GAIN vs. FREQUENCY
17
16
GAIN (dB)
V
CC
= 4.75V, 5.0V, AND 5.25V
MAX2027 toc07
18
17
16
GAIN (dB)
15
14
13
12
11
10
50
100
150
200
250
300
350
T
A
= +85°C
T
A
= -40°C
T
A
= +25°C
18
15
14
13
12
11
10
50
100
150
200
250
300
350
400
400
FREQUENCY (MHz)
FREQUENCY (MHz)
4
_______________________________________________________________________________________
IF Digitally Controlled Variable-Gain Amplifier
MAX2027
Typical Operating Characteristics (continued)
(Typical
application circuit, V
CC
= 5.0V, max gain (B0 = B1 = B2 = B3 = B4 = 0), P
OUT
= 5dBm, R
1
= 825Ω, T
A
= +25°C, unless
otherwise noted.)
ATTENUATION ABSOLUTE ACCURACY
(ALL STATES)
MAX2027 toc08
ATTENUATION RELATIVE ACCURACY
(ALL STATES)
MAX2027 toc09
NOISE FIGURE vs. FREQUENCY
6.5
6.0
NOISE FIGURE (dB)
5.5
5.0
4.5
4.0
3.5
3.0
2.5
2.0
T
A
= -40°C
T
A
= +25°C
T
A
= +85°C
MAX2027 toc10
1.0
0.8
ABSOLUTE ACCURACY (dB)
0.6
0.4
0.2
0
-0.2
-0.4
-0.6
-0.8
-1.0
50
100
150
200
250
300
350
1.0
0.8
RELATIVE ACCURACY (dB)
0.6
0.4
0.2
0
-0.2
-0.4
-0.6
-0.8
-1.0
7.0
400
50
100
150
200
250
300
350
400
50
100
150
200
250
300
350
400
FREQUENCY (MHz)
FREQUENCY (MHz)
FREQUENCY (MHz)
OUTPUT P-1dB vs. FREQUENCY
MAX2027 toc11
OUTPUT P-1dB vs. FREQUENCY
MAX2027 toc12
23
22
OUTPUT P-1dB (dBm)
21
20
19
T
A
= -40°C
18
17
50
100
150
200
250
300
350
T
A
= +85°C
T
A
= +25°C
23
22
OUTPUT P-1dB (dBm)
21
20
19
18
17
V
CC
= +4.75V
V
CC
= +5V
V
CC
= +5.25V
400
50
100
150
200
250
300
350
400
FREQUENCY (MHz)
FREQUENCY (MHz)
OUTPUT IP3 vs. FREQUENCY
MAX2027 toc13
OUTPUT IP3 vs. FREQUENCY
P
RF1
= P
RF2
= 5dBm
AT OUTPUT,
∆f
= 1MHz
MAX2027 toc14
40
P
RF1
= P
RF2
= 5dBm
AT OUTPUT,
∆f
= 1MHz
40
38
T
A
= -40°C
OIP3 (dBm)
36
T
A
= +25°C
38
V
CC
= +5.25V
OIP3 (dBm)
36
34
T
A
= +85°C
34
V
CC
= +5V
32
V
CC
= +4.75V
32
30
50
100
150
200
250
300
350
400
FREQUENCY (MHz)
30
50
100
150
200
250
300
350
400
FREQUENCY (MHz)
_______________________________________________________________________________________
5
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