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Transcript
19-5165; Rev 0; 3/10
250MHz to 4000MHz Dual,
Analog Voltage Variable Attenuator
The MAX19790 dual, general-purpose analog voltage
variable attenuator (VVA) is designed to interface with
50I systems operating in the 250MHz to 4000MHz frequency range. Each attenuator includes a control circuit
that provides 22dB of attenuation range with a linear
control slope of 10dB/V.
Both attenuators share a common analog control and
can be cascaded together to yield 44dB of total dynamic
range, with a combined linear control slope of 20dB/V.
The IC is a monolithic device designed on one of Maxim’s
proprietary SiGe BiCMOS processes. The device operates from a single +5.0V supply and is available in a compact, 36-pin thin QFN package (6mm x 6mm x 0.8mm)
with an exposed pad. Electrical performance is guaranteed over the extended -40° to +85°C temperature range.
Features
S 250MHz to 4000MHz RF Frequency Range
S Integrates Two Analog Attenuators in One
Monolithic Device
S Flexible Attenuation-Control Ranges
22dB (per Attenuator)
44dB (Both Attenuators Cascaded)
S 2.4dB 1500MHz Insertion Loss (per Attenuator)
S Linear dB/V Analog Control Response Curve
Simplifies Automatic Leveling Control and
Gain-Trim Algorithms
S Excellent Attenuation Flatness Over Wide
Frequency Ranges and Attenuation Settings
S Low 7.3mA Supply Current
S Single +5.0V Supply Voltage
Applications
Broadband System Applications, Including
Wireless Infrastructure Digital and SpreadSpectrum Communication Systems
WCDMA/LTE, TD-SCDMA/TD-LTE, WiMAX™,
cdma2000®, GSM/EDGE, and MMDS Base
Stations
VSAT/Satellite Modems
Ordering Information
PART
TEMP RANGE
PIN-PACKAGE
MAX19790ETX+
-40NC to +85NC
36 Thin QFN-EP*
MAX19790ETX+T
36 Thin QFN-EP*
-40NC to +85NC
+Denotes a lead(Pb)-free/RoHS-compliant package.
*EP = Exposed pad.
T = Tape and reel.
Microwave Terrestrial Links
Lineup Gain Trim
Temperature Compensation Circuits
Automatic Level Control (ALC)
Transmitter Gain Control
Receiver Gain Control
General Test Equipment
WiMAX is a trademark of WiMAX Forum.
cdma2000 is a registered trademark of Telecommunications
Industry Association.
________________________________________________________________ Maxim Integrated Products 1
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.
MAX19790
General Description
MAX19790
250MHz to 4000MHz Dual,
Analog Voltage Variable Attenuator
Absolute Maximum Ratings
VCC to GND...........................................................-0.3V to +5.5V
CTRL to GND (with VCC = +5.0V applied)............. 0V to +4.75V
All Other Pins to GND............................... -0.3V to (VCC + 0.3V)
RF Input.......................................................................... +20dBm
Current into CTRL Pin (VCC grounded)..............................40mA
Maximum Junction Temperature......................................+150°C
Operating Temperature Range........................... -40°C to +85°C
Storage Temperature Range.........................….-65°C to +150°C
Continuous Power Dissipation (TC = +85°C) (Note 1)........2.1W
θJC (Notes 2, 4)............................................................. +10°C/W
θJA (Notes 3, 4)............................................................. +35°C/W
Lead Temperature (soldering, 10s).................................+300°C
Soldering Temperature (reflow).......................................+260°C
Note 1: TC is the temperature on the exposed pad of the package. TA is the ambient temperature of the device and PCB.
Note 2: Based on junction temperature TJ = TC + (θJC x VCC x ICC). This formula can be used when the temperature of the exposed
pad is known while the device is soldered down to a PCB. See the Applications Information section for details. The junction
temperature must not exceed +150°C.
Note 3: Junction temperature TJ = TA + (θJA x VCC x ICC). This formula can be used when the ambient temperature of the PCB is
known. The junction temperature must not exceed +150°C.
Note 4: Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a fourlayer board. For detailed information on package thermal considerations, refer to www.maxim-ic.com/thermal-tutorial.
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.
CAUTION! ESD SENSITIVE DEVICE
DC ELECTRICAL CHARACTERISTICS
(VCC = +4.75V to +5.25V, VCTRL = +1.0V to +4.0V, no RF signals applied, all input and output ports terminated with 50I, TC =
-40°C to +85°C, unless otherwise noted. Typical values are at VCC = +5.0V, VCTRL = +1.0V, TC = +25°C, unless otherwise noted.)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
5.0
5.25
V
7.3
9.5
mA
SUPPLY
Supply Voltage
VCC
Supply Current
ICC
4.75
CONTROL INPUT
Control Voltage Range
VCTRL
Control Input Resistance
RCTRL
(Note 5)
1.0
4.0
50
V
kI
RECOMMENDED AC OPERATING CONDITIONS
PARAMETER
RF Frequency Range
2
SYMBOL
fRF
CONDITIONS
(Note 6)
MIN
250
TYP
MAX
UNITS
4000
MHz
250MHz to 4000MHz Dual,
Analog Voltage Variable Attenuator
(MAX19790 Evaluation Kit, line and connector losses included, two attenuators in cascade, VCC = 4.75V to 5.25V, RF ports are
driven from 50I sources, input PRF = -10dBm, fRF = 950MHz to 2150MHz, VCTRL = +1.0V, TC = -40°C to +85°C. Typical values are
for TC = +25°C, VCC = +5.0V, input PRF = -10dBm, fRF = 1500MHz, VCTRL = +1.0V, unless otherwise noted.)
PARAMETER
Insertion Loss
SYMBOL
IL
TC = +25NC
TYP
MAX
950MHz to 1500MHz
MIN
4.4
6.3
950MHz to 2150MHz
4.4
7.0
TC = -40NC to +85NC
Loss Variation Over Temperature
Input P1dB
CONDITIONS
IP1dB
UNITS
dB
0.6
dB
23.1
dBm
Input Second-Order Intercept
Point
IIP2
fRF1 + fRF2 term, fRF1 - fRF2 = 1MHz
(Note 7)
69.6
dBm
Input Third-Order Intercept Point
IIP3
fRF1 - fRF2 = 1MHz (Note 7)
36.3
dBm
Second Harmonic
2fIN
72
dBc
Third Harmonic
3fIN
77
dBc
One attenuator, VCTRL = +1.0V
to +4.0V, TC = +25NC
Attenuation-Control Range
AR
Two attenuators,
VCTRL = +1.0V
to +4.0V,
TC = +25NC
22
950MHz to 1500MHz
36
44.7
950MHz to 2150MHz
33
44.7
dB
Average Attenuation-Control
Slope
VCTRL = +1.0V to +3.5V
20.0
dB/V
Maximum Attenuation-Control
Slope
VCTRL = +1.0V to +3.5V
30.4
dB/V
Attenuation Flatness Over
125MHz Bandwidth (Note 8)
Peak-to-peak for VCTRL = +1.0V to +3.1V,
TC = +25NC
0.13
0.89
dB
Switching Time
From 15dB to 0dB attenuation (Note 9)
500
ns
Input Return Loss
All gain settings
25
dB
Output Return Loss
All gain settings
21
dB
Group Delay
Input/output 50I lines deembedded
190
ps
Group-Delay Flatness Over
125MHz Bandwidth
Peak-to-peak
10
ps
Group-Delay Change vs.
Attenuation Control
VCTRL = +1.0V to +4.0V
-175
ps
Insertion Phase Change vs.
Attenuation Control
VCTRL = +1.0V to +4.0V
82
Degrees
Note 5: Operating outside this range for extended periods may affect device reliability. Limit pin input current to 40mA when VCC
is not present (see Table 1 for R4 value).
Note 6: Operation outside this range is possible, but with degraded performance of some parameters. See the Typical Operating
Characteristics.
Note 7: f1 = 1500MHz, f2 = 1501MHz, -10dBm/tone at attenuator input.
Note 8: Guaranteed by design and characterization.
Note 9: Switching time is measured from 50% of the control signal to when the RF output settles to Q1dB.
3
MAX19790
AC ELECTRICAL CHARACTERISTICS
Typical Operating Characteristics
(MAX19790 Evaluation Kit, two attenuators in cascade, VCC = +5.0V, PRF = -10dBm, TC = +25NC, VCTRL = +1.0V, unless otherwise noted.)
SUPPLY CURRENT vs. VCC
INPUT MATCH vs. RF FREQUENCY
TC = +85°C
7.0
-10
S22 (dB)
TC = -40°C
-20
MAX19790 toc03
-10
0
MAX19790 toc02
MAX19790 toc01
TC = +85°C
TC = +25°C
7.5
OUTPUT MATCH vs. RF FREQUENCY
0
S11 (dB)
SUPPLY CURRENT (mA)
8.0
TC = +85°C
TC = -40°C
-20
TC = -40°C
-30
TC = +25°C
-30
TC = +25°C
5.125
-40
5.250
-40
1000
0
VCC (V)
2000
3000
4000MHz
-10
S11 (dB)
TC = +85°C
4000
OUTPUT MATCH vs. VCTRL
0
4000MHz
-10
250MHz
TC = +25°C
250MHz
500MHz
-20
500MHz
-20
4
-30
-30
950MHz
2150MHz
950MHz
-40
0
2000
3000
4000
2
3
-40
4
ATTENUATION vs. VCTRL
250MHz, 500MHz, 950MHz
-10
fRF = 950MHz
-10
2150MHz
S21 (dB)
-20
4000MHz
-30
-40
-40
-50
-50
-60
-60
1
2
3
VCTRL (V)
4
4
S21 PHASE CHANGE vs. VCTRL
ATTENUATION vs. VCTRL
-20
3
VCTRL (V)
0
MAX19790 toc07
0
-30
2
1
VCTRL (V)
RF FREQUENCY (MHz)
TC = -40°C, +25°C, +85°C
200
S21 PHASE CHANGE (DEGREES)
1000
1
MAX19790 toc08
0
2150MHz
REFERENCED TO INSERTION-LOSS STATE.
POSITIVE PHASE = ELECTRICALLY
SHORTER.
150
MAX19790 toc09
TC = -40°C
2
4
1000
0
RF FREQUENCY (MHz)
0
MAX19790 toc04
10
INSERTION LOSS (dB)
4000
INPUT MATCH vs. VCTRL
INSERTION LOSS vs. RF FREQUENCY
6
3000
RF FREQUENCY (MHz)
12
8
2000
MAX19790 toc06
5.000
S22 (dB)
4.875
MAX19790 toc05
6.5
4.750
S21 (dB)
MAX19790
250MHz to 4000MHz Dual,
Analog Voltage Variable Attenuator
2150MHz
4000MHz
100
50
950MHz
0
500MHz
250MHz
-50
1
2
3
VCTRL (V)
4
1
2
3
VCTRL (V)
4
250MHz to 4000MHz Dual,
Analog Voltage Variable Attenuator
35
30
40
35
30
1500MHz
2150MHz
TC = -40°C
25
PIN = -10dBm/TONE
950MHz
INPUT IP3 (dBm)
TC = +85°C
MAX19790 toc10
fRF = 950MHz
PIN = -10dBm/TONE
40
INPUT IP3 (dBm)
INPUT IP3 vs. VCTRL
45
MAX19790 toc11
INPUT IP3 vs. VCTRL
45
25
TC = +25°C
20
20
2
4
3
1
2
VCTRL (V)
INPUT IP2 vs. VCTRL
fRF = 950MHz
PIN = -10dBm/TONE
TC = +25°C
70
60
2
1500MHz
60
50
40
1
70
950MHz
TC = +85°C
TC = -40°C
50
PIN = -10dBm/TONE
2150MHz
80
INPUT IP2 (dBm)
80
INPUT IP2 (dBm)
INPUT IP2 vs. VCTRL
90
MAX19790 toc12
90
40
4
3
1
2
VCTRL (V)
INPUT P1dB vs. RF FREQUENCY
INPUT P1dB vs. RF FREQUENCY
TC = -40°C
MAX19790 toc15
26
MAX19790 toc14
26
25
INPUT P1dB (dBm)
INPUT P1dB (dBm)
VCC = 5.25V
24
23
22
TC = +25°C
21
4
3
VCTRL (V)
25
4
3
VCTRL (V)
MAX19790 toc13
1
24
VCC = 5.0V
23
VCC = 4.75V
22
21
TC = +85°C
20
20
950
1350
1750
RF FREQUENCY (MHz)
2150
950
1350
1750
2150
RF FREQUENCY (MHz)
5
MAX19790
Typical Operating Characteristics (continued)
(MAX19790 Evaluation Kit, two attenuators in cascade, VCC = +5.0V, PRF = -10dBm, TC = +25NC, VCTRL = +1.0V, unless otherwise noted.)
Typical Operating Characteristics (continued)
(MAX19790 Evaluation Kit, one attenuator connected, VCC = +5.0V, PRF = -10dBm, TC = +25NC, VCTRL = +1.0V, unless otherwise noted.)
INPUT MATCH vs. RF FREQUENCY
7.0
S22 (dB)
-20
-30
TC = -40°C
-10
TC = +25°C
TC = +25°C
7.5
0
MAX19790 toc17
MAX19790 toc16
TC = +85°C
-10
S11 (dB)
TC = +85°C
-20
-30
TC = -40°C
-40
-40
TC = -40°C
4.875
5.000
5.125
5.250
-50
0
1000
VCC (V)
INSERTION LOSS vs. RF FREQUENCY
3000
4000
0
1000
MAX19790 toc19
6
4000MHz
-10
250MHz
500MHz
TC = +85°C
2
4000MHz
-10
2150MHz
2150MHz
-20
-30
-40
TC = -40°C
-30
-40
3000
4000
1
2
RF FREQUENCY (MHz)
-10
4000MHz
-15
-20
-20
-25
-25
TC = -40°C, +25°C, +85°C
-30
-30
2
3
VCTRL (V)
6
fRF = 950MHz
-5
S21 (dB)
2150MHz
4
1
2
3
VCTRL (V)
3
4
S21 PHASE CHANGE vs. VCTRL
-10
-15
1
2
1
VCTRL (V)
0
MAX19790 toc22
250MHz, 500MHz, 950MHz
-5
4
ATTENUATION vs. VCTRL
ATTENUATION vs. VCTRL
0
3
VCTRL (V)
4
100
MAX19790 toc24
2000
-50
S21 PHASE CHANGE (DEGREES)
1000
950MHz
-50
MAX19790 toc23
0
250MHz
500MHz
-20
950MHz
0
4000
3000
OUTPUT MATCH vs. VCTRL
0
S22 (dB)
TC = +25°C
2000
RF FREQUENCY (MHz)
INPUT MATCH vs. VCTRL
0
S11 (dB)
INSERTION LOSS (dB)
2000
RF FREQUENCY (MHz)
8
4
TC = +25°C
-50
MAX19790 toc20
6.5
4.750
MAX19790 toc21
SUPPLY CURRENT (mA)
TC = +85°C
OUTPUT MATCH vs. RF FREQUENCY
0
MAX19790 toc18
SUPPLY CURRENT vs. VCC
8.0
S21 (dB)
MAX19790
250MHz to 4000MHz Dual,
Analog Voltage Variable Attenuator
75
4000MHz
50
2150MHz
950MHz
25
250MHz
0
500MHz
-25
REFERENCED TO INSERTION-LOSS STATE.
POSITIVE PHASE = ELECTRICALLY SHORTER.
-50
1
2
3
VCTRL (V)
4
250MHz to 4000MHz Dual,
Analog Voltage Variable Attenuator
INPUT IP3 vs. VCTRL
35
30
TC = +25°C
TC = -40°C
25
PIN = -10dBm/TONE
1500MHz
40
INPUT IP3 (dBm)
35
950MHz
30
25
2150MHz
TC = +85°C
20
20
2
1
3
4
2
1
VCTRL (V)
INPUT IP2 vs. VCTRL
fRF = 950MHz
PIN = -10dBm/TONE
TC = +85°C
80
TC = +25°C
70
PIN = -10dBm/TONE
90
INPUT IP2 (dBm)
INPUT IP2 (dBm)
90
4
INPUT IP2 vs. VCTRL
100
MAX19790 toc27
100
3
VCTRL (V)
60
1500MHz
MAX19790 toc28
INPUT IP3 (dBm)
40
MAX19790 toc25
fRF = 950MHz
PIN = -10dBm/TONE
45
MAX19790 toc26
INPUT IP3 vs. VCTRL
45
80
70
2150MHz
60
950MHz
TC = -40°C
1
50
2
3
4
1
2
VCTRL (V)
INPUT P1dB vs. RF FREQUENCY
INPUT P1dB vs. RF FREQUENCY
TC = -40°C
25
23
22
VCC = 5.0V
VCC = 5.25V
INPUT P1dB (dBm)
INPUT P1dB (dBm)
25
24
23
22
VCC = 4.75V
TC = +85°C
21
4
26
MAX19790 toc29
26
24
3
VCTRL (V)
MAX19790 toc30
50
21
TC = +25°C
20
20
950
1350
1750
RF FREQUENCY (MHz)
2150
950
1350
1750
2150
RF FREQUENCY (MHz)
7
MAX19790
Typical Operating Characteristics (continued)
(MAX19790 Evaluation Kit, one attenuator connected, VCC = +5.0V, PRF = -10dBm, TC = +25NC, VCTRL = +1.0V, unless otherwise noted.)
250MHz to 4000MHz Dual,
Analog Voltage Variable Attenuator
GND
GND
GND
GND
GND
GND
GND
TOP VIEW
GND
GND
MAX19790
Pin Configuration/Functional Diagram
27 26 25 24 23 22 21 20 19
GND
GND
30
VCC
GND
32
GND
IN_B
34
GND
36
MAX19790
29
ATTEN_B
31
ATTENUATIONCONTROL
CIRCUITRY
33
18
GND
17
16
GND
GND
15
GND
14
11
GND
VCC
GND
CTRL
10
GND
13
12
ATTEN_A
35
*EP
2
3
4
5
6
7
VCC
GND
GND
GND
1
OUT_A
GND
GND
+
8
9
GND
28
IN_A
GND
OUT_B
THIN QFN
*EXPOSED PAD.
Pin Description
8
PIN
NAME
1, 3, 4, 6, 7, 9, 10,
12, 14–28, 30, 31,
33, 34, 36
FUNCTION
GND
2
OUT_A
5, 13, 32
VCC
Power Supply. Bypass to GND with capacitors and resistors as shown in the Typical
Application Circuit.
8
IN_A
Attenuator A Input. Internally matched to 50I over the operating frequency band. This pin,
if used, requires a DC block. If this attenuator is not used, the pin can be left unconnected.
11
CTRL
Analog Attenuator Control Input. VCC must be present unless using a current-limiting resistor, as noted in the Applications Information section. Limit voltages applied to this pin to a
+1.0V to +4.0V range with VCC present to ensure device reliability.
29
OUT_B
Attenuator B Output. Internally matched to 50I over the operating frequency band. This pin,
if used, requires a DC block. If this attenuator is not used, the pin can be left unconnected.
35
IN_B
Attenuator B Input. Internally matched to 50I over the operating frequency band. This pin,
if used, requires a DC block. If this attenuator is not used, the pin can be left unconnected.
—
EP
Exposed Pad. Internally connected to GND. Solder evenly to the board’s ground plane for
proper operation.
Ground. Connect to the board’s ground plane using low-inductance layout techniques.
Attenuator A Output. Internally matched to 50I over the operating frequency band. This pin,
if used, requires a DC block. If this attenuator is not used, the pin can be left unconnected.
250MHz to 4000MHz Dual,
Analog Voltage Variable Attenuator
The MAX19790 is a dual, general-purpose analog voltage variable attenuator (VVA) designed to interface
with 50I systems operating in the 250MHz to 4000MHz
frequency range. Each attenuator includes a control
circuit that provides 22dB of attenuation range with a
linear control slope of 10dB/V. Both attenuators share a
common analog control and can be cascaded together
to yield 44dB of total dynamic range, with a combined
linear control slope of 20dB/V.
Applications Information
Analog Attenuation Control
A single input voltage at the CTRL pin adjusts the attenuation of the device. Up to 22dB of attenuation-control
range is provided per attenuator. At the insertion-loss
setting, the attenuator’s loss is approximately 2.4dB.
If a larger attenuation-control range is desired, the
second on-chip attenuator can be connected in series to
provide an additional 22dB of gain-control range.
Note that the CTRL pin simultaneously adjusts both
on-chip attenuators. The CTRL input voltage drives a
high-impedance load (> 50kI). It is suggested that a
current-limiting resistor be included in series with this
connection, to limit the input current to less than 40mA,
should the control voltage be applied when VCC is not
present. A series resistor of greater than 200I provides
complete protection for +5.0V control voltage ranges.
Note: To ensure the reliability of the device, limit CTRL
input voltages to a +1.0V to +4.0V range when VCC is
present.
Layout Considerations
A properly designed PCB is an essential part of any
RF/microwave circuit. Keep RF signal lines as short as
possible to reduce losses, radiation, and inductance.
For best performance, route the ground-pin traces
directly to the exposed pad underneath the package.
This pad MUST be connected to the ground plane of
the board by using multiple vias under the device to
provide the best RF and thermal conduction path. Solder
the exposed pad on the bottom of the device package
to a PCB.
Power-Supply Bypassing
Proper voltage-supply bypassing is essential for highfrequency circuit stability. Bypass each VCC pin with
capacitors placed as close as possible to the device.
Place the smallest capacitor closest to the device. See
the Typical Application Circuit and Table 1 for details.
Table 1. Typical Application Circuit Component Values
DESIGNATION
QTY
DESCRIPTION
C1, C3, C5
3
220pF Q5%, 50V C0G ceramic
capacitors (0402)
Murata GRM1555C1H221J
C2, C4
2
0.01FF Q10%, 25V X7R ceramic
capacitors (0402)
Murata GRM155R71E103K
C6
1
1000pF Q5%, 50V C0G ceramic
capacitor (0402)
Murata GRM1555C1H102J
C7
1
0.1FF Q10%, 16V X7R ceramic
capacitor (0603)
Murata GRM188R71C104K
C8*
0
Not installed, ceramic capacitor
(0603)
DESIGNATION
QTY
C9
1
22pF Q5%, 50V C0G ceramic
capacitor (0402)
Murata GRM1555C1H220J
R1, R2
2
10I Q5% resistors (0402)
Any
2
0I resistors (0402)
Note: In cases where VCTRL is
applied before or removed after
VCC, use R4 = 200I.
1
Analog attenuator IC
Maxim MAX19790ETX+
Note: U1 has an exposed pad
conductor, which requires it to be
solder-attached to a grounded
pad on the PCB to ensure a
proper electrical/thermal design.
R3, R4
U1
DESCRIPTION
*C8 can be used to provide additional filtering. Depending on the external driver used on the CTRL line, this capacitance could
slow down the response time.
9
MAX19790
Detailed Description
Exposed Pad RF and Thermal
Considerations
The EP MUST be soldered to a ground plane on the
PCB, either directly or through an array of plated via
holes. Soldering the pad to ground is also critical
for efficient heat transfer. Use a solid ground plane
wherever possible.
The exposed pad (EP) of the device’s 36-pin thin QFN
package provides a low thermal-resistance path to
the die. It is important that the PCB on which the IC is
mounted be designed to conduct heat from this contact.
In addition, provide the EP with a low-inductance RF
ground path for the device.
27
VCC
GND
GND
IN_B
GND
GND
GND
GND
GND
GND
GND
GND
19
18
29
17
MAX19790
30
16
ATTEN_B
31
15
ATTENUATIONCONTROL
CIRCUITRY
32
14
13
33
34
EP
ATTEN_A
12
35
11
36
10
OUT_A
2
3
4
5
6
7
8
9
GND
GND
VCC
GND
R3
GND
C7
GND
C6
VCC
GND
C9
CTRL
GND
C8
R4
CTRL
R1
C1
RFA
VCC
RFB*
20
28
1
C3
21
GND
VCC
R2
22
IN_A
GND
23
GND
GND
C4
24
GND
OUT_B
25
VCC
C5
26
GND
GND
GND
RFOUT
GND
GND
Typical Application Circuit
GND
MAX19790
250MHz to 4000MHz Dual,
Analog Voltage Variable Attenuator
C2
*SCHEMATIC SHOWS CONFIGURATION FOR TWO CASCADED ATTENUATORS. TO USE ATTENUATOR A ONLY MOVE C3
TO CONNECT OUT_A TO RFB. TO USE ATTENUATOR B ONLY MOVE C3 TO CONNECT RFB TO IN_B.
10
250MHz to 4000MHz Dual,
Analog Voltage Variable Attenuator
Package Information
For the latest package outline information and land patterns,
go to www.maxim-ic.com/packages. Note that a “+”, “#”, or
“-” in the package code indicates RoHS status only. Package
drawings may show a different suffix character, but the drawing
pertains to the package regardless of RoHS status.
PACKAGE TYPE
PACKAGE CODE
Document No.
36 Thin QFN-EP
T3666+2
21-0141
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied.
Maxim reserves the right to change the circuitry and specifications without notice at any time.
Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600
© 2010
Maxim Integrated Products 11
Maxim is a registered trademark of Maxim Integrated Products, Inc.
MAX19790
Chip Information
PROCESS: BiCMOS