General Description
The MAX2683/MAX2684 are super-high-performance,
low-cost downconverter mixers intended for wireless
local loop (WLL) and digital microwave radio (DMR)
applications in the 3.4GHz to 3.8GHz frequency band.
The MAX2683 is optimized for downconversion to IF
frequencies between 100MHz and 400MHz, and allows
both high-side and low-side local oscillator (LO) injection. The MAX2684 is optimized for IF frequencies
between 800MHz and 1000MHz, and allows low-side
LO injection. A logic-level control enables an internal
frequency doubler on both devices, allowing the external LO source to run at full or half frequency. An internal
LO filter reduces LO harmonics and spurious mixing.
The MAX2683/MAX2684 feature an externally adjustable
bias control, set with a single resistor, that lets the user
trade supply current for linearity to optimize system performance. These devices use a double-balanced
Gilbert-cell architecture with single-ended RF and LO
inputs and differential open-collector IF output ports.
Differential IF ports provide a wideband, flexible interface for either single-ended or differential applications.
The MAX2683/MAX2684 operate from a single +2.7V to
+5.5V supply. The devices are packaged in an ultrasmall 16-pin TSSOP-EP package with an exposed paddle for optimum performance at 3.5GHz.
________________________Applications
Wireless Local Loop (WLL)
Digital Microwave Radio (DMR)
Wireless Broadband Access
Features
♦ 3.4GHz to 3.8GHz RF Frequency Range
♦ 100MHz to 400MHz IF Frequency Range
(MAX2683)
800MHz to 1000MHz IF Frequency Range
(MAX2684)
♦ Logic-Enabled LO Frequency Doubler
♦ Conversion Gain
+6.7dB (MAX2683)
+1dB (MAX2684)
♦ Programmable IIP3
+7dBm to +11dBm (MAX2683)
+8dBm to +12dBm (MAX2684)
♦ +2.7V to +5.5V Single-Supply Operation
♦ Ultra-Small 16-Pin TSSOP-EP Package
MAX2683/MAX2684
3.5GHz Downconverter Mixers
with Selectable LO Doubler
________________________________________________________________ Maxim Integrated Products 1
Pin Configuration
19-1620; Rev 1; 5/01
EVALUATION KIT
AVAILABLE
Ordering Information
Typical Operating Circuit appears at end of data sheet.
16 TSSOP-EP*
PIN-PACKAGETEMP. RANGE
-40°C to +85°C
MAX2683EUE
PART
16 TSSOP-EP*-40°C to +85°C
MAX2684EUE
*Exposed pad
Functional Diagram
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.
16
BIAS
15
GND
14
IFOUT+
MAX2683
MAX2684
TSSOP-EP
13
GND
12
GND
IFOUT-
11
10
GND
9
GND
RFIN
V
BIAS
GND
TOP VIEW
IFOUT+
IFOUT-
CC
BIAS
LO
BUFFER
x1
MAX2683
MAX2684
LOX1 LOX2
DOUBLER
LO
x2
ENX2
V
GND
GND
RFIN
GND
ENX2
LOX2
LOX1
1
CC
2
3
4
5
6
7
8
MAX2683/MAX2684
3.5GHz Downconverter Mixers
with Selectable LO Doubler
2 _______________________________________________________________________________________
ABSOLUTE MAXIMUM RATINGS
DC ELECTRICAL CHARACTERISTICS
(VCC= +2.7V to +5.5V; R
BIAS
= 1.2kΩ; ENX2 = GND; RFIN, LOX1, and LOX2 are terminated in 50Ω, no input signal applied; IFOUT+
= IFOUT- = V
CC
, TA= -40°C to +85°C, unless otherwise noted. Typical values are at VCC= +5V, TA= +25°C.) (Note 1)
AC ELECTRICAL CHARACTERISTICS—MAX2683
(MAX2683/MAX2684 EV kit, VCC= +5V, R
BIAS
= 1.2kΩ, ENX2 = GND, fRF= 3.6GHz, PRF= -20dBm, f
LOX2
= 1650MHz, PLO= -5dBm,
all input/output ports terminated in 50Ω, IFOUT+ and IFOUT- matched to single-ended 50Ω load, T
A
= +25°C, unless otherwise noted.)
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.
VCCto GND...........................................................-0.3V to +6.0V
IFOUT+, IFOUT-, ENX2, BIAS to GND .......-0.3V to (V
CC
+ 0.3V)
RFIN Input Power (50Ω source) .....................................+10dBm
LO Input Power (50Ω source) ........................................+10dBm
R
BIAS
.............................................................................820Ω min
Continuous Power Dissipation (TA= +70°C)
16-pin TSSOP-EP (derate 21.3mW/°C
above +70°C).............................................................1702mW
Operating Temperature Range ...........................-40°C to +85°C
Junction Temperature......................................................+150°C
Storage Temperature Range ..............................-65°C to+150°C
Lead Temperature (soldering, 10s) .................................+300°C
PARAMETER
MIN TYP MAX
UNITS
Gain Variation Over
Temperature
±0.5 ±1.2 dB
Conversion Gain 4.8 6.7 8.0 dB
Input 1dB Compression Point +0.8 dBm
Input Third-Order Intercept Point +8.8 dBm
Input Second-Order Intercept
Point
+33 dBm
Noise Figure 12 dB
IF Frequency Range
RF Frequency Range 3.4 3.8 GHz
100 400 MHz
LOX1 Frequency Range 3.0 3.9 GHz
RFIN Input Return Loss -18 dB
LOX2 Leakage at RFIN
-42
dBm
-38
-49
LOX1 Leakage at RFIN -39 dBm
CONDITIONS
(Note 8)
TA= -40°C to +85°C (Note 2)
f
RFIN
= 3 × f
LO
(Notes 1, 4)
(Note 5)
(Note 6)
(Note 7)
(Notes 2, 3)
(Notes 2, 3)
ENX2 = V
CC
(Notes 2, 3)
f
RFIN
= 2 × f
LO
f
RFIN
= 1 × f
LO
ENX2 = GND
LOX2 Frequency Range 1.5 1.95 GHz
ENX2 = GND (Notes 2, 3)
ENX2 = VCC,f
RFIN
= 1 × f
LO, fLOX1
= 3.3GHz
PARAMETER
MIN TYP MAX
UNITS
Input Logic Bias Current
-20 10
µA
Input Logic Voltage Low
0.6
V
Supply Current Reduction when
LO Doubler is Disabled
Supply Current
55 66
mA
15
mA
Input Logic Voltage High
2.0
V
CONDITIONS
ENX2 = V
CC
MAX2683/MAX2684
3.5GHz Downconverter Mixers
with Selectable LO Doubler
_______________________________________________________________________________________ 3
AC ELECTRICAL CHARACTERISTICS—MAX2683 (continued)
(MAX2683/MAX2684 EV kit, VCC= +5V, R
BIAS
= 1.2kΩ, ENX2 = GND, fRF= 3.6GHz, PRF= -20dBm, f
LOX2
= 1650MHz, PLO= -5dBm,
all input/output ports terminated in 50Ω, IFOUT+ and IFOUT- matched to single-ended 50Ω load, T
A
= +25°C, unless otherwise noted.)
AC ELECTRICAL CHARACTERISTICS—MAX2684
(MAX2683/MAX2684 EV kit, VCC= +5V, R
BIAS
= 1.2kΩ, ENX2 = GND, fRF= 3.6GHz, PRF= -20dBm, f
LOX2
= 1350MHz, PLO= -5dBm,
all input/output ports terminated in 50Ω, IFOUT+ and IFOUT- matched to single-ended 50Ω load, T
A
= +25°C, unless otherwise noted.)
Note 1: Limits over temperature are guaranteed by production test at +25°C and via correlation to worst-case temperature testing.
Note 2: Minimum and maximum limits are guaranteed by design and characterization, but are not production tested.
Note 3: The device has been characterized over the specified frequency range. Operation outside of this range is possible but not
guaranteed.
PARAMETER
LOX2 Leakage at IFOUT+,
IFOUT-
-39
dBm-39
-64
LOX1 Leakage at IFOUT+,
IFOUT-
-39 dBm
LOX1, LOX2 Input Return Loss -20 dB
f
IFOUT
= 3 × f
LO
f
IFOUT
= 2 × f
LO
ENX2 = GND
(Note 9)
f
IFOUT
= 1 × f
LO
f
RFIN
= 3 × f
LOX2
f
RFIN
= 2 × f
LOX2
f
RFIN
= 1 × f
LOX2
f
RFIN
= 3 × f
LOX2
f
RFIN
= 2 × f
LOX2
f
RFIN
= 1 × f
LOX2
LOX1 Leakage at IFOUT+,
IFOUT-
-15 dBm
LOX1, LOX2 Input Return Loss -20 dB(Note 9)
LOX2 Leakage at IFOUT+,
IFOUT-
-37
dBm
ENX2 = GND
-20
-41
-49
LOX1 Leakage at RFIN -45 dBm
Noise Figure 13.6 dB
RFIN Input Return Loss -18 dB(Note 8)
(Note 7)
LOX2 Leakage at RFIN
-47
dBm-43
ENX2 = GND
Input Third-Order Intercept Point +9.5 dBm
Input Second-Order Intercept
Point
+37 dBm(Note 11)
(Note 10)
PARAMETER
MIN TYP MAX
UNITS
Conversion Gain -0.8 +1 +2.3 dB
LOX1 Frequency Range 2.4 2.9 GHz
Gain Variation Over
Temperature and Frequency
±0.5 ±1.2 dB
IF Frequency Range
RF Frequency Range 3.4 3.8 GHz
800 1000 MHz
LOX2 Frequency Range 1.2 1.45 GHz
Input 1dB Compression Point 0 dBm
CONDITIONS
(Notes 1, 4)
LOX2 = VCC(Notes 2, 3)
TA= -40°C to +85°C
(Notes 2, 3)
(Notes 2, 3)
LOX2 = GND (Notes 2, 3)
ENX2 = VCC, f
IFOUT
= 1 × f
LO, fLOX1
= 3.3GHz
ENX2 = VCC, f
RFIN
= 1 × f
LOX1, fLOX1
= 2.7GHz
ENX2 = VCC, f
IFOUT
= 1 × f
LOX1, fLOX1
= 2.7GHz
MIN TYP MAX
UNITS
CONDITIONS
MAX2683/MAX2684
3.5GHz Downconverter Mixers
with Selectable LO Doubler
4 _______________________________________________________________________________________
Typical Operating Characteristics
(MAX2683/MAX2684 EV kit, VCC= +5V, R
BIAS
= 1.2kΩ, ENX2 = GND, fRF= 3.6GHz, PRF= -20dBm, f
LOX2
= 1650MHz for MAX2683 or
f
LOX2
= 1350MHz for MAX2684, PLO= -5dBm, all input/output ports terminated in 50Ω, IFOUT+ and IFOUT- matched to single-ended
50Ω load, TA= +25°C, unless otherwise noted.)
0
30
20
10
40
50
60
70
80
90
100
2.5 3.53.0 4.0 4.5 5.0 5.5
SUPPLY CURRENT vs. SUPPLY VOLTAGE
(ENX2 = GND)
MAX2683/4 toc01
SUPPLY VOLTAGE (V)
SUPPLY CURRENT (mA)
TA = -40°C
R
BIAS
= 820Ω
R
BIAS
= 1.2kΩ
R
BIAS
= 2.0kΩ
TA = +25°C
TA = +85°C
0
30
20
10
40
50
60
70
80
90
100
2.5 3.53.0 4.0 4.5 5.0 5.5
SUPPLY CURRENT vs. SUPPLY VOLTAGE
(ENX2 = V
CC
)
MAX2683/4 toc02
SUPPLY VOLTAGE (V)
SUPPLY CURRENT (mA)
TA = +85°C
TA = +25°C
R
BIAS
= 820Ω
R
BIAS
= 1.2kΩ
R
BIAS
= 2.0kΩ
TA = -40°C
20
35
30
25
40
45
50
55
60
65
70
800 12001000 1400 1600 1800 2000
SUPPLY CURRENT vs. R
BIAS
MAX2683/4 toc03
R
BIAS
(Ω)
SUPPLY CURRENT (mA)
VCC = +5V
VCC = +5V
VCC = +3.3V
VCC = +3.3V
ENX2 = V
CC
ENX2 = GND
5.0
5.5
6.5
6.0
7.0
7.5
800 12001000 1400 1600 1800 2000
CONVERSION GAIN vs. R
BIAS
MAX2683 toc04
R
BIAS
(Ω)
CONVERSION GAIN (dB)
VCC = +5V
VCC = +3.3V
5
7
6
9
8
10
11
800 1200 14001000 1600 1800 2000
INPUT IP3 vs. R
BIAS
MAX2683/4 toc05
R
BIAS
(Ω)
INPUT IP3 (dBm)
VCC = +5V
VCC = +3.3V
-3
-1
-2
1
0
2
3
800 1200 14001000 1600 1800 2000
INPUT P1dB vs. R
BIAS
MAX2683 toc06
R
BIAS
(Ω)
INPUT P1dB (dBm)
VCC = +5V
VCC = +3.3V
MAX2683
Note 4: Conversion gain does not include output balun losses, typically 0.3dB at 300MHz on the MAX2683 EV kit and 0.8dB at
900MHz on the MAX2684 EV kit.
Note 5: IIP3 measured with two tones at 3605MHz and 3610MHz, -20dBm per tone, f
IF
= 300MHz.
Note 6: IIP2 measured with f
RFIN
= 3450MHz, P
RFIN
= -20dBm, fIF= 300MHz.
Note 7: Input match optimized for best return loss at f
RF
= 3600MHz.
Note 8: Over specified RF input frequency range with matching network.
Note 9: Over specified LO input frequency range.
Note 10: IIP3 measured with two tones at 3605MHz and 3610MHz, -20dBm per tone, f
IF
= 900MHz.
Note 11: IIP2 measured with f
RFIN
= 3150MHz, P
RFIN
= -20dBm, fIF= 900MHz.
MAX2683/MAX2684
3.5GHz Downconverter Mixers
with Selectable LO Doubler
_______________________________________________________________________________________ 5
Typical Operating Characteristics (continued)
(MAX2683/MAX2684 EV kit, VCC= +5V, R
BIAS
= 1.2kΩ, ENX2 = GND, fRF= 3.6GHz, PRF= -20dBm, f
LOX2
= 1650MHz for MAX2683 or
f
LOX2
= 1350MHz for MAX2684, PLO= -5dBm, all input/output ports terminated in 50Ω, IFOUT+ and IFOUT- matched to single-ended
50Ω load, T
A
= +25°C, unless otherwise noted.)
MAX2683
CONVERSION GAIN vs. LO POWER
(ENX2 = GND)
10
TA = -40°C
8
6
4
2
0
-2
-4
CONVERSION GAIN (dB)
-6
-8
-10
-20 -15 -10 -5 0
TA = +25°C
TA = +85°C
LO POWER (dBm)
CONVERSION GAIN vs. SUPPLY VOLTAGE
= 820Ω)
(R
10
TA = -40°C
9
8
7
6
5
4
3
CONVERSION GAIN (dB)
2
1
0
2.5 3.53.0 4.0 4.5 5.0 5.5
BIAS
TA = +25°C
TA = +85°C
SUPPLY VOLTAGE (V)
INPUT IP3 vs. SUPPLY VOLTAGE
= 820Ω)
(R
15
12
BIAS
10
MAX2683 toc07
-2
-4
CONVERSION GAIN (dB)
-6
-8
-10
CONVERSION GAIN vs. LO POWER
(ENX2 = V
TA = -40°C
8
6
4
2
0
TA = +85°C
-20 -15 -10 -5 0
LO POWER (dBm)
)
CC
MAX2683 toc08
TA = +25°C
CONVERSION GAIN vs. SUPPLY VOLTAGE
= 1.2kΩ)
(R
10
MAX2683 toc10
CONVERSION GAIN (dB)
9
8
7
6
5
TA = +85°C
4
3
2
1
0
2.5 3.53.0 4.0 4.5 5.0 5.5
BIAS
TA = -40°C
ENX2 = V
CC
ENX2 = GND
SUPPLY VOLTAGE (V)
MAX2683 toc11
TA = +25°C
INPUT IP3 vs. SUPPLY VOLTAGE
= 1.2kΩ)
(R
BIAS
TA = +25°C
TA = +85°C
MAX2683 toc14
MAX2683 toc13
10
9
NOISE FIGURE vs. LO POWER
30
25
20
15
NOSIE FIGURE (dB)
10
5
0
-16 -12-14 -10 -8 -6 -4 -2 0
LO POWER (dBm)
CONVERSION GAIN vs. SUPPLY VOLTAGE
= 2kΩ)
(R
10
9
8
7
6
5
4
3
CONVERSION GAIN (dB)
2
1
0
2.5 3.53.0 4.0 4.5 5.0 5.5
BIAS
TA = -40°C
TA = +25°C
TA = +85°C
SUPPLY VOLTAGE (V)
INPUT IP3 vs. SUPPLY VOLTAGE
= 2kΩ)
(R
10
9
BIAS
MAX2683 toc09
MAX2683 toc12
MAX2683 toc15
9
TA = +25°C
6
INPUT IP3 (dBm)
3
0
2.5 3.53.0 4.0 4.5 5.0 5.5
TA = +85°C
SUPPLY VOLTAGE (V)
TA = -40°C
8
7
INPUT IP3 (dBm)
6
5
2.5 3.53.0 4.0 4.5 5.0 5.5
TA = -40°C
SUPPLY VOLTAGE (V)
8
TA = +85°C
7
INPUT IP3 (dBm)
6
5
2.5 3.53.0 4.0 4.5 5.0 5.5
TA = -40°C
TA = +25°C
SUPPLY VOLTAGE (V)
MAX2683/MAX2684
3.5GHz Downconverter Mixers
with Selectable LO Doubler
6 _______________________________________________________________________________________
Typical Operating Characteristics (continued)
(MAX2683/MAX2684 EV kit, VCC= +5V, R
BIAS
= 1.2kΩ, ENX2 = GND, fRF= 3.6GHz, PRF= -20dBm, f
LOX2
= 1650MHz for MAX2683 or
f
LOX2
= 1350MHz for MAX2684, PLO= -5dBm, all input/output ports terminated in 50Ω, IFOUT+ and IFOUT- matched to single-ended
50Ω load, TA= +25°C, unless otherwise noted.)
MAX2683
INPUT P1dB vs. SUPPLY VOLTAGE
= 820Ω)
(R
10
BIAS
INPUT P1dB vs. SUPPLY VOLTAGE
3
(R
BIAS
= 1.2kΩ)
INPUT P1dB vs. SUPPLY VOLTAGE
= 2kΩ)
(R
0
BIAS
6
2
-2
INPUT P1dB (dBm)
-6
-10
2.5 3.53.0 4.0 4.5 5.0 5.5
TA = +25°C
TA = -40°C
TA = +85°C
SUPPLY VOLTAGE (V)
MAX2683 toc16
INPUT P1dB (dBm)
CONVERSION GAIN vs. RF FREQUENCY
= 1.2kΩ)
(R
10
9
8
7
6
5
TA = +85°C
4
3
CONVERSION GAIN (dB)
2
1
0
3400 3500 35503450 3600 3650 3700 3750 3800
BIAS
ENX2 = V
CC
ENX2 = GND
RF FREQUENCY (MHz)
TA = -40°C
TA = +25°C
MAX2683 toc19
CONVERSION GAIN (dB)
LOX2 PORT RETURN LOSS vs.
LO FREQUENCY (ENX2 = GND)
0
2
1
TA = +25°C
0
-1
-2
2.5 3.53.0 4.0 4.5 5.0 5.5
SUPPLY VOLTAGE (V)
TA = +85°C
TA = -40°C
CONVERSION GAIN vs. FREQUENCY
(ENX2 = GND)
10
9
8
7
6
5
4
3
2
1
0
250 290270 310 330 350
TA = +85°C
IF PORT NARROWBAND MATCH AT 300MHz
IF FREQUENCY (MHz)
TA = -40°C
TA = +25°C
0
MAX2683 toc17
-1
TA = -40°C
-2
-3
INPUT P1dB (dBm)
-4
-5
2.5 3.53.0 4.0 4.5 5.0 5.5
CONVERSION GAIN vs. IF FREQUENCY
10
9
MAX2683 toc20
8
7
6
5
4
3
CONVERSION GAIN (dB)
2
1
0
250 290270 310 330 350
TA = +85°C
IF PORT NARROWBAND MATCH AT 300MHz
LOX1 PORT RETURN LOSS
vs. LO FREQUENCY (ENX2 = V
TA = +85°C
SUPPLY VOLTAGE (V)
(ENX2 = V
IF FREQUENCY (MHz)
)
CC
)
CC
TA = +25°C
MAX2683 toc18
TA = +25°C
TA = -40°C
MAX2683 toc21
-20
-40
-60
RETURN LOSS (dB)
-80
-100
1500 17001600 1800 1900 2000
LO FREQUENCY (MHz)
MAX2683 toc22
-10
-20
-30
RETURN LOSS (dB)
-40
-50
3000 33603180 3540 3720 3900
LO FREQUENCY (MHz)
MAX2683 toc23
MAX2683/MAX2684
3.5GHz Downconverter Mixers
with Selectable LO Doubler
_______________________________________________________________________________________ 7
Typical Operating Characteristics (continued)
(MAX2683/MAX2684 EV kit, VCC= +5V, R
BIAS
= 1.2kΩ, ENX2 = GND, fRF= 3.6GHz, PRF= -20dBm, f
LOX2
= 1650MHz for MAX2683 or
f
LOX2
= 1350MHz for MAX2684, PLO= -5dBm, all input/output ports terminated in 50Ω, IFOUT+ and IFOUT- matched to single-ended
50Ω load, TA= +25°C, unless otherwise noted.)
LOX1 S11 vs. R
(ENX2 = VCC)
820Ω
1.2kΩ
2kΩ
MAX2683
IF PORT S11 vs. R
BIAS
BIAS
MAX2683
LOX2 S11 vs. R
(ENX2 = GND)
1.2kΩ,
2kΩ, 820Ω
MAX2683
RFIN S11 vs. R
BIAS
BIAS
1.2kΩ,
2kΩ, 820kΩ
2kΩ,
1.2kΩ, 820kΩ
MAX2683/MAX2684
3.5GHz Downconverter Mixers
with Selectable LO Doubler
8 _______________________________________________________________________________________
Typical Operating Characteristics (continued)
(MAX2683/MAX2684 EV kit, VCC= +5V, R
BIAS
= 1.2kΩ, ENX2 = GND, fRF= 3.6GHz, PRF= -20dBm, f
LOX2
= 1650MHz for MAX2683 or
f
LOX2
= 1350MHz for MAX2684, PLO= -5dBm, all input/output ports terminated in 50Ω, IFOUT+ and IFOUT- matched to single-ended
50Ω load, TA= +25°C, unless otherwise noted.)
0
30
20
10
40
50
60
70
80
90
100
2.5 3.53.0 4.0 4.5 5.0 5.5
SUPPLY CURRENT vs. SUPPLY VOLTAGE
(ENX2 = GND)
MAX2683/4 toc28
SUPPLY VOLTAGE (V)
SUPPLY CURRENT (mA)
TA = -40°C
R
BIAS
= 820Ω
R
BIAS
= 1.2kΩ
R
BIAS
= 2.0kΩ
TA = +85°C
TA = +25°C
0
30
20
10
40
50
60
70
80
90
100
2.5 3.53.0 4.0 4.5 5.0 5.5
SUPPLY CURRENT vs. SUPPLY VOLTAGE
(ENX2 = V
CC
)
MAX2683/4 toc29
SUPPLY VOLTAGE (V)
SUPPLY CURRENT (mA)
TA = +85°C
TA = +25°C
R
BIAS
= 820Ω
R
BIAS
= 1.2kΩ
R
BIAS
= 2.0kΩ
TA = -40°C
20
35
30
25
40
45
50
55
60
65
70
800 12001000 1400 1600 1800 2000
SUPPLY CURRENT vs. R
BIAS
MAX2683/4 toc30
R
BIAS
(Ω)
SUPPLY CURRENT (mA)
VCC = +5V
VCC = +5V
VCC = +3.3V
VCC = +3.3V
ENX2 = V
CC
ENX2 = GND
-0.2
0.6
0.4
0.2
0
1.0
0.8
1.2
1.4
800 1200 14001000 1600 1800 2000
CONVERSION GAIN vs. R
BIAS
MAX2683/4 toc31
R
BIAS
(Ω)
CONVERSION GAIN (dB)
VCC = +3.3V
VCC = +5V
6
8
7
10
9
12
11
13
800 1200 14001000 1600 1800 2000
INPUT IP3 vs. R
BIAS
MAX2683/4 toc32
R
BIAS
(Ω)
INPUT IP3 (dBm)
VCC = +5V
VCC = +3.3V
-4
-2
-3
0
-1
2
1
3
800 1200 14001000 1600 1800 2000
INPUT P1dB vs. R
BIAS
MAX2683/4 toc33
R
BIAS
(Ω)
INPUT P1dB (dBm)
VCC = +5V
VCC = +3.3V
MAX2684
CONVERSION GAIN vs. LO POWER
5
4
TA = -40°C
3
2
1
0
-1
-2
CONVERSION GAIN (dB)
-3
-4
-5
-20 -15 -10 -5 0
(ENX2 = GND)
TA = +85°C
LO POWER (dBm)
TA = +25°C
MAX2683 toc34
-1
-2
CONVERSION GAIN (dB)
-3
-4
-5
CONVERSION GAIN vs. LO POWER
5
(ENX2 = V
4
3
2
1
0
-20 -15 -10 -5 0
TA = -40°C
TA = +25°C
LO POWER (dBm)
)
CC
TA = +85°C
MAX2683 toc35
NOISE FIGURE vs. LO POWER
20
19
18
17
16
15
14
NOISE FIGURE (dB)
13
12
11
10
-16 -12 -10-14 -8 -6 -4 -2 0
LO POWER (dBm)
MAX2683 toc36
MAX2683/MAX2684
3.5GHz Downconverter Mixers
with Selectable LO Doubler
_______________________________________________________________________________________ 9
MAX2684
Typical Operating Characteristics (continued)
(MAX2683/MAX2684 EV kit, VCC= +5V, R
BIAS
= 1.2kΩ, ENX2 = GND, fRF= 3.6GHz, PRF= -20dBm, f
LOX2
= 1650MHz for MAX2683 or
f
LOX2
= 1350MHz for MAX2684, PLO= -5dBm, all input/output ports terminated in 50Ω, IFOUT+ and IFOUT- matched to single-ended
50Ω load, TA= +25°C, unless otherwise noted.)
-10
-6
2
-2
6
10
2.5 3.53.0 4.0 4.5 5.0 5.5
INPUT P1dB vs. SUPPLY VOLTAGE
(R
BIAS
= 820Ω)
MAX2683 toc43
SUPPLY VOLTAGE (V)
INPUT P1dB (dBm)
TA = +85°C
TA = -40°C
TA = +25°C
-5
-2
-3
-4
-1
0
1
2
3
4
5
2.5 3.53.0 4.0 4.5 5.0 5.5
INPUT P1dB vs. SUPPLY VOLTAGE
(R
BIAS
= 1.2kΩ)
MAX2683 toc44
SUPPLY VOLTAGE (V)
INPUT P1dB (dBm)
TA = +85°C
TA = -40°C
TA = +25°C
-10
-7
-8
-9
-6
-5
-4
-3
-2
-1
0
2.5 3.53.0 4.0 4.5 5.0 5.5
INPUT P1dB vs. SUPPLY VOLTAGE
(R
BIAS
= 2kΩ)
MAX2683 toc45
SUPPLY VOLTAGE (V)
INPUT P1dB (dBm)
TA = +85°C
TA = +25°C
TA = -40°C
CONVERSION GAIN vs. SUPPLY VOLTAGE
= 820Ω)
(R
5
4
TA = -40°C
3
2
1
0
-1
-2
CONVERSION GAIN (dB)
-3
-4
-5
2.5 3.53.0 4.0 4.5 5.0 5.5
BIAS
TA = +25°C
SUPPLY VOLTAGE (V)
TA = +85°C
INPUT IP3 vs. SUPPLY VOLTAGE
= 820Ω)
(R
15
12
TA = +25°C
9
6
INPUT IP3 (dBm)
3
0
2.5 3.53.0 4.0 4.5 5.0 5.5
BIAS
TA = +85°C
TA = -40°C
SUPPLY VOLTAGE (V)
MAX2683 toc37
-1
CONVERSION GAIN (dB)
-2
-3
CONVERSION GAIN vs SUPPLY VOLTAGE
3
2
1
0
ENX2 = V
ENX2 = GND
2.5 3.53.0 4.0 4.5 5.0 5.5
= 1.2kΩ)
(R
BIAS
TA = -40°C
T
= +25°C
A
CC
SUPPLY VOLTAGE (V)
MAX2683 toc38
TA = +85°C
INPUT IP3 vs. SUPPLY VOLTAGE
= 1.2kΩ)
(R
BIAS
MAX2683 toc41
TA = -40°C
TA = +25°C
SUPPLY VOLTAGE (V)
MAX2683 toc40
15
14
13
12
11
TA = +85°C
10
9
INPUT IP3 (dBm)
8
7
6
5
2.5 3.53.0 4.0 4.5 5.0 5.5
CONVERSION GAIN vs. SUPPLY VOLTAGE
= 2kΩ)
(R
5
4
3
2
1
0
-1
-2
CONVERSION GAIN (dB)
-3
-4
-5
2.5 3.53.0 4.0 4.5 5.0 5.5
BIAS
TA = -40°C
TA = +25°C
TA = +85°C
SUPPLY VOLTAGE (V)
INPUT IP3 vs. SUPPLY VOLTAGE
= 2kΩ)
(R
10
9
TA = -+85°C
8
7
6
5
4
INPUT IP3 (dBm)
3
2
1
0
2.5 3.53.0 4.0 4.5 5.0 5.5
BIAS
SUPPLY VOLTAGE (V)
MAX2683 toc39
MAX2683 toc42
TA = -40°CTA = +25°C
MAX2683/MAX2684
3.5GHz Downconverter Mixers
with Selectable LO Doubler
10 ______________________________________________________________________________________
MAX2684
Typical Operating Characteristics (continued)
(MAX2683/MAX2684 EV kit, VCC= +5V, R
BIAS
= 1.2kΩ, ENX2 = GND, fRF= 3.6GHz, PRF= -20dBm, f
LOX2
= 1650MHz for MAX2683 or
f
LOX2
= 1350MHz for MAX2684, PLO= -5dBm, all input/output ports terminated in 50Ω, IFOUT+ and IFOUT- matched to single-ended
50Ω load, TA= +25°C, unless otherwise noted.)
-5
-2
-3
-4
-1
0
1
2
3
4
5
3400 35003450 3550 3600 3650 3700 3750 3800
MAX2683 toc46
RF FREQUENCY (MHz)
CONVERSION GAIN (dB)
CONVERSION GAIN vs. RF FREQUENCY
(ENX2 = GND)
TA = +25°C
TA = +85°C
TA = -40°C
-5
-2
-3
-4
-1
0
1
2
3
4
5
3400 35003450 3550 3600 3650 3700 3750 3800
MAX2683 toc47
RF FREQUENCY (MHz)
CONVERSION GAIN (dB)
CONVERSION GAIN vs. RF FREQUENCY
(ENX2 = V
CC
)
TA = +25°C
TA = +85°C
TA = -40°C
-5
-2
-3
-4
-1
0
1
2
3
4
5
860 900880 920 940 960
MAX2683 toc48
IF FREQUENCY (MHz)
CONVERSION GAIN (dB)
CONVERSION GAIN vs. IF FREQUENCY
(ENX2 = GND)
TA = +25°C
TA = +85°C
TA = -40°C
CONVERSION GAIN vs. IF FREQUENCY
5
4
TA = -40°C
3
2
1
0
-1
-2
CONVERSION GAIN (dB)
-3
-4
-5
860 900880 920 940 960
IF FREQUENCY (MHz)
(ENX2 = V
TA = +25°C
TA = +85°C
)
CC
LOX1 S11 vs. R
1.2kΩ, 2kΩ,
820Ω
MAX2683 toc49
(ENX2 = VCC)
LOX2 PORT RETURN LOSS
vs. LO FREQUENCY
0
-10
-20
-30
RETURN LOSS (dB)
-40
-50
1200 13001250 1350 1400 1450
LO FREQUENCY (MHz)
BIAS
0
MAX2683 toc50
-10
-20
-30
RETURN LOSS (dB)
-40
-50
2400 26002500 2700 2800 2900
LOX2 S11 vs. R
(ENX2 = GND)
1.2kΩ,
2kΩ, 820Ω
LOX1 PORT RETURN LOSS
vs. LO FREQUENCY
MAX2683 toc51
LO FREQUENCY (MHz)
BIAS
MAX2683/MAX2684
3.5GHz Downconverter Mixers
with Selectable LO Doubler
______________________________________________________________________________________ 11
Pin Description
IF PORT S11 vs. R
BIAS
1.2kΩ,
2kΩ, 820kΩ
MAX2684
NAME FUNCTION
1
V
CC
Supply Voltage Input. Bypass with a 100pF capacitor as close to the pin as possible.
2, 3, 5, 9,
10, 12, 13,
15, EP
GND
Ground. Connect to ground plane with a low-inductance connection. Solder exposed paddle
evenly to the board ground plane.
PIN
4 RFIN
RF Input Port to Mixer. Requires a matching network and a DC-blocking capacitor that may be part
of this network.
6
ENX2
LO Frequency-Doubler Enable Input. Drive low to enable the LO doubler and run external LO at
half frequency. Drive high to disable the LO doubler and run external LO at full frequency.
16 BIAS
Bias-Setting Resistor Connection. A resistor, R
BIAS
, placed from BIAS to GND sets the linearity and
supply current of the mixer.
11, 14
IFOUT-,
IFOUT+
Differential, Open-Collector IF Output Ports of Mixer. Requires a matching network and pull-up
inductors to VCCthat can be part of this network.
8 LOX1
Full-Frequency Local-Oscillator Input to Downconverter Mixer. Requires a DC-blocking capacitor.
Leave unconnected if this pin is not used.
7 LOX2
Half-Frequency Local-Oscillator Input to LO Frequency Doubler, LO Filter, and Downconverter
Mixer. Requires a DC-blocking capacitor. Leave unconnected if this pin is not used.
RFIN S11 vs. R
BIAS
2kΩ,
1.2kΩ, 820kΩ
Typical Operating Characteristics (continued)
(MAX2683/MAX2684 EV kit, VCC= +5V, R
BIAS
= 1.2kΩ, ENX2 = GND, fRF= 3.6GHz, PRF= -20dBm, f
LOX2
= 1650MHz for MAX2683 or
f
LOX2
= 1350MHz for MAX2684, PLO= -5dBm, all input/output ports terminated in 50Ω, IFOUT+ and IFOUT- matched to single-ended
50Ω load, TA= +25°C, unless otherwise noted.)
MAX2683/MAX2684
3.5GHz Downconverter Mixers
with Selectable LO Doubler
12 ______________________________________________________________________________________
Detailed Description
The MAX2683/MAX2684 are double-balanced downconverter mixers optimized for the 3.4GHz to 3.8GHz
frequency band. The MAX2683 is designed for downconversion to IF frequencies of 100MHz to 400MHz,
while the MAX2684 is designed for IF frequencies of
800MHz to 1000MHz. In addition, the devices include a
logic-level LO frequency doubler, an integrated LO filter, and externally programmable bias control circuitry.
RF Input
RFIN is a single-ended input that accepts frequencies
in the 3.4GHz to 3.8GHz range. It requires a matching
network and a DC-blocking capacitor that may be part
of this network. See Typical Operation Circuit for recommended component values. See Table 1 for RFIN
port S-parameters.
LO Inputs, LO Frequency Doubler,
and LO Filter
The MAX2683/MAX2684 feature an internal LO frequency doubler that allows the external LO to run at full or
half frequency. Running the LO at half frequency has
the benefit of reducing unwanted LO leakage through
the low-noise amplifier (LNA) to the antenna, reducing
injection pulling of the voltage-controlled oscillator
R
BIAS
= 2kΩ
S11 PHASE
(degrees)
-126.0
-124.7
-123.5
-122.3
3600
R
BIAS
= 1.2kΩ
S11 MAG
S11 PHASE
(degrees)
S11 MAG
0.570 -125.1 0.547
0.567 -123.7 0.544
0.564 -122.5 0.540
0.561 -121.3 0.536
R
BIAS
= 820Ω
RF
FREQUENCY
(MHz)
S11 MAG
S11 PHASE
(degrees)
3550 0.594 -117.5
3500 0.590 -116.2
3450 0.586 -114.8
3400 0.582 -113.3
0.599 -118.7 0.574 -126.1 0.553 -127.0
3650 0.602 -120.0 0.576 -127.2 0.555 -128.1
3700 0.607 -121.2 0.580 -128.3 0.559 -129.1
3750 0.608 -122.3 0.583 -129.3 0.563 -130.1
3800 0.612 -123.5 0.587 -130.2 0.567 -131.0
3400 0.578 -117.5 0.537 -119.7 0.512 -121.3
3450 0.582 -119.0 0.542 -121.2 0.518 -122.7
3500 0.586 -120.5 0.545 -122.6 0.523 -124.1
3550 0.590 -121.8 0.545 -122.7 0.527 -125.5
3600 0.595 -123.1 0.555 -125.4 0.533 -126.8
3650 0.599 -124.5 0.558 -126.7 0.537 -128.0
3700 0.604 -125.7 0.564 -127.8 0.542 -129.1
3750 0.606 -126.7 0.568 -128.9 0.546 -130.2
3800 0.611 -127.9 0.572 -129.9 0.552 -13.1
MAX2683
MAX2684
Table 1. MAX2683/MAX2684 RFIN Port S-Parameters (VCC= +5V, TA= +25°C)
MAX2683/MAX2684
3.5GHz Downconverter Mixers
with Selectable LO Doubler
______________________________________________________________________________________ 13
(VCO) from the PA, and reducing the demands of
designing a high-frequency VCO. An internal LO bandpass filter is integrated after the frequency doubler to
help reduce LO harmonic content and spurious mixing.
To enable the LO frequency doubler, drive ENX2 to a
logic-low level and connect the half-frequency external
LO to the LOX2 port. To disable and bypass the LO frequency doubler and LO filter, drive ENX2 to a logichigh level and connect the full-frequency external LO to
1800 0.254 -98.9 3600 0.271 -164.9
1875 0.262
LOX1
(ENX2 = VCC)
LOX2
FREQUENCY
(MHz)
S11 MAG
S11 PHASE
(degrees)
3450 0.306 -167.3
3300 0.338 -167.0
3150 0.358 -165.4
3000 0.362 -163.5
LOX2
(ENX2 = GND)
LOX2
FREQUENCY
(MHz)
S11 MAG
S11 PHASE
(degrees)
1725 0.247 -95.3
1650 0.241 -91.1
1575 0.237 -86.7
1500 0.234 -82.0
-102.3 3750 0.235 -160.6
1950 0.268 -104.9 3900 0.200 -154.8
1500 0.211 -77.9 3000 0.343 -159.1
1575 0.213 -83.7 3150 0.341 -160.0
1650 0.217 -89.3 3300 0.330 -162.3
1725 0.222 -94.5 3450 0.310 -162.0
1800 0.230 -99.3 3600 0.285 -160.2
1875 0.240 -103.6 3750 0.256 -156.4
1950 0.249 -107.1 3900 0.224 -151.1
1500 0.213 -78.0 3000 0.339 -155.2
1575 0.214 -83.7 3150 0.340 -156.0
1650 0.218 -89.3 3300 0.332 -156.0
1725 0.223 -94.5 3450 0.315 -155.3
1800 0.231 -99.3 3600 0.294 -153.3
1875 0.241 -103.7 3750 0.268 -150.0
1950 0.249 -107.2 3900 0.240 -145.5
R
BIAS
= 820Ω
R
BIAS
= 1.2kΩ
R
BIAS
= 2.0kΩ
Table 2. MAX2683 LO Port S-Parameters (VCC= +5V, TA= +25°C)
MAX2683/MAX2684
3.5GHz Downconverter Mixers
with Selectable LO Doubler
14 ______________________________________________________________________________________
the LOX1 port. Disabling the LO doubler has the benefit of reducing the supply current by 15mA. See Tables
2 and 3 for the LO input frequency ranges.
LOX1 and LOX2 are single-ended LO inputs that
achieve a return loss of typically -20dB over the specified LO input frequency range. They are internally
biased and require a DC-blocking capacitor. To
improve LOX2 input return loss, use a series inductor
between the blocking capacitor and LOX2 input. See
the Typical Operating Circuit for recommended component values. See Tables 2 and 3 for LOX1 and LOX2
S-parameters. Leave the unused port unconnected.
IF Output
The MAX2683 is optimized for IF frequencies in the
100MHz to 400MHz range, while the MAX2684 is optimized for IF frequencies in the 900MHz to 1000MHz
range. The differential, open-collector IFOUT- and
IFOUT+ ports require external pull-up inductors to VCC,
1400 0.210 -72.4 2800 0.305 -158.8
1450 0.209
LOX1
(ENX2 = VCC)
LOX1
FREQUENCY
(MHz)
S11 MAG
S11 PHASE
(degrees)
2700 0.296 -152.1
2600 0.281 -147.5
2500 0.266 -143.5
2400 0.249 -138.9
LOX2
(ENX2 = GND)
LOX2
FREQUENCY
(MHz)
S11 MAG
S11 PHASE
(degrees)
1350 0.212 -69.1
1300 0.215 -66.0
1250 0.219 -62.8
1200 0.225 -59.6
-75.4 2900 0.302 -167.3
1200 0.228 -64.7 2400 0.235 -135.3
1250 0.222 -68.9 2500 0.251 -139.8
1300 0.219 -71.2 2600 0.265 -143.5
1350 0.216 -74.4 2700 0.280 -147.8
1400 0.214 -77.8 2800 0.290 -152.8
1450 0.213 -81.0 2900 0.292 -157.0
1200 0.212 -75.4 2400 0.224 -132.3
1250 0.222 -63.1 2500 0.240 -136.6
1300 0.217 -66.2 2600 0.255 -140.1
1350 0.213 -69.2 2700 0.269 -143.8
1400 0.211 -72.3 2800 0.279 -147.6
1450 0.209 -75.3 2900 0.283 -150.3
R
BIAS
= 820Ω
R
BIAS
= 1.2kΩ
R
BIAS
= 2.0kΩ
Table 3. MAX2684 LO Port S-Parameters (VCC= +5V, TA= +25°C)
MAX2683/MAX2684
3.5GHz Downconverter Mixers
with Selectable LO Doubler
______________________________________________________________________________________ 15
as well as an output matching network for optimum performance. See Typical Operating Circuit for recommended component values. See Tables 4 and 5 for IFOUT
port S-parameters.
Bias Circuitry
The linearity and supply current of the MAX2683/
MAX2684 are externally programmable with a single
resistor, R
BIAS
, from BIAS to GND. A nominal resistor
value of 1.2kΩ will set an IIP3 of +9dBm and a supply
current of 55mA. Decreasing the resistor value
improves linearity at the cost of increased supply current. Increasing the resistor value decreases supply
current while degrading linearity. Use resistor values in
the range of 820kΩ to 2kΩ.
___________
Applications Information
Layout Considerations
A properly designed PC board is an essential part of
any RF/microwave circuit. Keep RF signal lines as short
as possible to reduce losses, radiation, and inductance. Use separate, low-inductance vias to the ground
plane for each ground pin. For best performance, solder the exposed pad on the bottom of the device package evenly to the board ground plane.
Power-Supply and
ENX2
Bypassing
Proper voltage-supply bypassing is essential for highfrequency circuit stability. Bypass VCCwith a 10µF
capacitor in parallel with a 100pF capacitor located as
close to the VCCpin as possible.
Bypass ENX2 with a 100pF capacitor to ground to minimize noise injected into the LO doubler cell. Use a
series resistor (typically 1.2kΩ) to further reduce coupling of high-frequency signals into the ENX2 pin.
R
BIAS
= 1.2kΩ
S11 PHASE
(degrees)
-10.9
-23.5
-20.3
-17.2
-14.2
R
BIAS
= 1.2kΩ
S11 MAG
S11 PHASE
(degrees)
S11 MAG
0.914 -11.2 0.930
0.893 -24.5 0.907
0.900 -21.3 0.911
0.905 -17.8 0.917
0.905 -14.7 0.920
R
BIAS
= 820Ω
RF
FREQUENCY
(MHz)
S11 MAG
S11 PHASE
(degrees)
150 0.915 -11.3
350 0.894 -24.5
300 0.899 -21.3
250 0.904 -17.7
200 0.907 -14.8
R
BIAS
= 1.2kΩ
S11 PHASE
(degrees)
-49.7
-53.3
-52.3
-51.4
-50.6
960
R
BIAS
= 1.2kΩ
S11 MAG
S11 PHASE
(degrees)
S11 MAG
0.955 -49.6 0.955
0.940 -53.1 0.937
0.944 -52.3 0.941
0.948 -51.4 0.946
0.952 -50.5 0.950
R
BIAS
= 820Ω
RF
FREQUENCY
(MHz)
S11 MAG
S11 PHASE
(degrees)
860 0.955 -49.4
940 0.943 -53.0
920 0.946 -52.0
900 0.950 -51.1
880 0.952 -50.3
0.941 -53.6 0.936 -54.0 0.935 -53.8
Table 5. MAX2684 IFOUT Port S-Parameters (VCC= +5V, TA= +25°C)
Table 4. MAX2683 IFOUT Port S-Parameters (VCC= +5V, TA= +25°C)
MAX2683/MAX2684
3.5GHz Downconverter Mixers
with Selectable LO Doubler
16 ______________________________________________________________________________________
Typical Operating Circuit
V
CC
1
100pF
10µF
RF
INPUT
LO DOUBLER
ENABLE
OFF
ON
HALF-FREQUENCY
LO INPUT
NOTE: EVENLY SOLDER EXPOSED PAD (EP)
ON BOTTOM OF DEVICE TO GROUND PLANE.
3300pF
1.2k
100pF
FULL-FREQUENCY
LO INPUT
1.2nH
1pF
100pF
3.9nH
100pF
2
3
4
5
6
7
8
V
CC
GND
GND
MAX2683
RFIN
GND
ENX2
LOX2
LOX1
IFOUT+
GND
GND
IFOUT-
MAX2684 IF OUTPUT DIFFERENTIAL
TO SINGLE-ENDED CONVERSION NETWORK.
BIAS
GND
IFOUT+
GND
GND
IFOUT-
GND
GND
14
13
12
11
16
15
14
13
12
11
10
9
300Ω
6.8nH
6.8nH
V
1.5kΩ
8.2pF
CC
8.2pF
R
BIAS
1.5k
0.01µF
39nH
39nH
8.2pF
300MHz
V
CC
3.3pF
0.01µF
8.2pF
900MHz
IF OUTPUT
BALUN
IF OUTPUT
BALUN
MAX2683/MAX2684
3.5GHz Downconverter Mixers
with Selectable LO Doubler
Package Information
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 ____________________ 17
© 2001 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products.
TSSOP.EPS
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