19-1673; Rev 0a; 4/02
UAL
IT MAN
TION K E
A
EVALU
BL
AVAILA
45MHz to 650MHz, Integrated IF
VCOs with Differential Output
Features
o
Small Size
o
Integrated Varactor for Tuning
o
Low Phase Noise
o
Wide Application Frequency Range
o
Differential or Single-Ended Outputs
o
Single +2.7V to +5.5V Supply
o
Ultra-Small SOT23-6 Package
o
On-Chip Temperature-Stable Bias
o
Low-Current Operation
General Description
The MAX2605–MAX2609 are compact, high-performance
intermediate-frequency (IF) voltage-controlled oscillators
(VCOs) designed specifically for demanding portable
wireless communication systems. They combine monolith-
ic construction with low-noise, low-power operation in a
tiny 6-pin SOT23 package.
These low-noise VCOs feature an on-chip varactor and
feedback capacitors that eliminate the need for external
tuning elements, making the MAX2605–MAX2609 ideal
for portable systems. Only an external inductor is
required to set the oscillation frequency. In addition, an
integrated differential output buffer is provided for dri-
ving a mixer or prescaler. The buffer output is capable
of supplying up to -8dBm (differential) with a simple
power match. It also provides isolation from load
impedance variations.
The MAX2605–MAX2609 operate from a single +2.7V to
+5.5V supply and offer low current consumption. These IF
oscillators can cover the 45MHz to 650MHz frequency
range.
MAX2605–MAX2609
Ordering Information
PART
TEMP. RANGE
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
PIN-
PACKAGE
6 SOT23-6
6 SOT23-6
6 SOT23-6
6 SOT23-6
6 SOT23-6
TOP
MARK
AABB
AABC
AABD
AABE
AABF
Applications
Cellular and PCS Mobile Phones
2.4GHz ISM Band
902MHz to 928MHz ISM Band
Land Mobile Radio
GPS Receivers
General-Purpose IF Oscillators
MAX2605EUT-T
MAX2606EUT-T
MAX2607EUT-T
MAX2608EUT-T
MAX2609EUT-T
Selector Guide
PART
MAX2605
MAX2606
MAX2607
MAX2608
MAX2609
FREQUENCY
RANGE
(MHz)
45 to 70
70 to 150
150 to 300
300 to 500
500 to 650
SUPPLY
CURRENT
(mA)
1.9
2.1
2.1
2.7
3.6
PHASE
NOISE
(dBc/Hz)
-117
-112
-107
-100
-93
IND
1
Pin Configuration/
Functional Diagram
TOP VIEW
GND
2
MAX2605
MAX2606
MAX2607
MAX2608
MAX2609
6
OUT+
5
V
CC
TUNE
3
4
OUT-
SOT23-6
________________________________________________________________
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.
45MHz to 650MHz, Integrated IF
VCOs with Differential Output
MAX2605–MAX2609
ABSOLUTE MAXIMUM RATINGS
V
CC
to GND ..............................................................-0.3V to +6V
IND to GND ................................................-0.6V to (V
CC
+ 0.3V)
TUNE to GND .............................................-0.3V to (V
CC
+ 0.3V)
OUT+, OUT- to GND ..................................-0.3V to (V
CC
+ 0.6V)
Continuous Power Dissipation (T
A
= +85°C)
6-Pin SOT23 (derate
8.7
mW/°C above +70°C) ...........696mW
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
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
(V
CC
= +2.7V to +5.5V, V
TUNE
= 0.4V to 2.4V, T
A
= -40°C to +85°C, unless otherwise noted. Typical values are at V
CC
= +2.75V,
V
TUNE
= 1.5V, and T
A
= +25°C.) (Note1)
PARAMETER
Supply Voltage
MAX2605
MAX2606
Supply Current (Note 2)
MAX2607
MAX2608
MAX2609
DC Output Current (Note 3)
TUNE Input Current
OUT+ plus OUT-
T
A
= +25°C
T
A
= -40°C to +85°C
T
A
= +25°C
T
A
= -40°C to +85°C
T
A
= +25°C
T
A
= -40°C to +85°C
T
A
= +25°C
T
A
= -40°C to +85°C
T
A
= +25°C
T
A
= -40°C to +85°C
0.5
1.0
0.03
3.6
2.7
2.1
2.1
CONDITIONS
MIN
2.7
1.9
TYP
MAX
5.5
2.6
2.8
2.7
3.0
3.2
3.5
4.4
5.5
6.8
7.5
1.5
mA
nA
mA
UNITS
V
2
_______________________________________________________________________________________
45MHz to 650MHz, Integrated IF
VCOs with Differential Output
AC ELECTRICAL CHARACTERISTICS
(MAX2605–MAX2609 EV kits, V
CC
= +2.7V to +5.5V, V
TUNE
= 0.4V to 2.4V, T
A
= -40°C to +85°C, unless otherwise noted. Typical val-
ues are at V
CC
= +2.75V, V
TUNE
= 1.5V, and T
A
= +25°C.) (Note 1)
PARAMETER
MAX2605
MAX2606
Oscillator Nominal Frequency
Range (Note 4)
MAX2607
MAX2608
MAX2609
MAX2605
MAX2606
Guaranteed Frequency Limits
(relative to nominal) (Note 5)
MAX2607
MAX2608
MAX2609
Peak Tuning Gain
Single-Ended Output Power
(Note 7)
MAX2605, Q
L
≥
35
MAX2606, Q
L
≥
35
Phase Noise (Note 8)
f
OFFSET
= 100kHz
MAX2607, Q
L
≥
35
MAX2608, Q
L
≥
40
MAX2609, Q
L
≥
40
T
A
= +25°C
T
A
= -40°C to +85°C
T
A
= +25°C
T
A
= -40°C to +85°C
T
A
= +25°C
T
A
= -40°C to +85°C
T
A
= +25°C
T
A
= -40°C to +85°C
T
A
= +25°C
T
A
= -40°C to +85°C
CONDITIONS
MIN
45
70
150
300
500
-4.1
-2.25
-4.4
-2.5
-4.6
-2.75
-4.7
-2.8
-5.0
-3.0
14.5
-10
-117
-112
-107
-100
-93
dBc/Hz
TYP
MAX
70
150
300
500
650
+3.2
+2.25
+3.4
+2.5
+3.6
+2.75
+3.6
+2.8
+3.8
+3.0
%/V
dBm
%
MHz
UNITS
MAX2605–MAX2609
V
TUNE
= 0.4V to 0.6V step (Note 6)
_______________________________________________________________________________________
3
45MHz to 650MHz, Integrated IF
VCOs with Differential Output
MAX2605–MAX2609
AC ELECTRICAL CHARACTERISTICS (continued)
(MAX2605–MAX2609 EV kits, V
CC
= +2.7V to +5.5V, V
TUNE
= 0.4V to 2.4V, T
A
= -40°C to +85°C, unless otherwise noted. Typical val-
ues are at V
CC
= +2.75V, V
TUNE
= 1.5V, and T
A
= +25°C.) (Note 1)
PARAMETER
Even-Order Harmonics
MAX2605
MAX2606
Supply Pushing (Note 9)
MAX2607
MAX2608
MAX2609
CONDITIONS
Differential, R
L
= 50Ω each side
MIN
TYP
-30
60
120
220
480
720
kHz/V
MAX
UNITS
dBc
Note 1:
Production tested at T
A
= +25°C. Maximum and minimum over temperature limits are guaranteed by design and
characterization.
Note 2:
Supply current is measured while the part is oscillating and inductor Q
≥
Q
MIN
. For MAX2605/MAX2606/MAX2607, Q
MIN
= 35;
for MAX2608/MAX2609, Q
MIN
= 40.
Note 3:
The DC output current is the total available output signal current.
Note 4:
Application range of the part is achieved using external inductance as specified in Figures 1-5 and shown in Figure 6. The inter-
nal varactors support center frequencies of 45MHz to 650MHz. The center frequency is defined by the value of the external
inductor element, L
F
. The application frequency limits are guaranteed by design and characterization.
Note 5:
The guaranteed (tested) limits ƒ
MIN
and ƒ
MAX
are measured at V
TUNE
= 0.4V and V
TUNE
= 2.4V, respectively. Passing
requirements are: ƒ
≤
ƒ
MIN
at V
TUNE
= 0.4 and ƒ
≥
ƒ
MAX
at V
TUNE
= 2.4V. The nominal frequency of oscillation is defined by
the inductor.
Note 6:
Describes peak tuning gain, which occurs at V
TUNE
= 0.4V.
Note 7:
Measurement at OUT+ or OUT- matched for optimum power transfer into 50Ω load near the center of the operating frequency
range.
Note 8:
The phase-noise specifications listed apply to the typical operating circuit shown in Figure 6. Apply over the entire operating
frequency range of the MAX2605–MAX2609.
Note 9:
Supply pushing is measured with V
CC
stepped from +2.7V to +3.2V.
Typical Operating Characteristics
(MAX260_ EV kit, V
CC
= +2.75V, V
TUNE
= 1.4V, T
A
= +25°C, unless otherwise noted.)
SUPPLY CURRENT
vs. TEMPERATURE
MAX2605/9-01
TUNE INPUT LEAKAGE CURRENT
vs. TEMPERATURE
MAX2605/9-02
MAX2605
VCO TUNING CURVE
MAX2605/9-03
4.0
3.5
SUPPLY CURRENT (mA)
MAX2609
3.0
2.5
2.0
1.5
1.0
-40
-20
0
20
40
60
80
TEMPERATURE (°C)
MAX2608 MAX2607
MAX2606
0.10
65
0.08
LEAKAGE CURRENT (nA)
60
FREQUENCY (MHz)
0.06
55
0.04
50
0.02
MAX2605
0
-40
-20
0
20
40
60
80
TEMPERATURE (°C)
45
0
0.5
1.0
1.5
V
TUNE
(V)
2.0
2.5
3.0
4
_______________________________________________________________________________________
45MHz to 650MHz, Integrated IF
VCOs with Differential Output
MAX2605–MAX2609
Typical Operating Characteristics (continued)
(MAX260_ EV kit, V
CC
= +2.75V, V
TUNE
= 1.4V, T
A
= +25°C, unless otherwise noted.)
MAX2606
VCO TUNING CURVE
MAX2605/9-04
MAX2607
VCO TUNING CURVE
MAX2605/9-05
MAX2608
VCO TUNING CURVE
MAX2605/9-06
130
260
430
240
FREQUENCY (MHz)
120
FREQUENCY (MHz)
220
FREQUENCY (MHz)
0
0.5
1.0
1.5
V
TUNE
(V)
2.0
2.5
3.0
400
110
370
200
100
180
340
90
0
0.5
1.0
1.5
V
TUNE
(V)
2.0
2.5
3.0
160
310
0
0.5
1.0
1.5
V
TUNE
(V)
2.0
2.5
3.0
MAX2609
VCO TUNING CURVE
MAX2605/9-07
OUTPUT SPECTRUM
MAX2605/9-08
680
0
640
FREQUENCY (MHz)
-10
600
(dB)
560
-20
-30
520
-40
480
0
0.5
1.0
1.5
V
TUNE
(V)
2.0
2.5
3.0
-50
f
o
2f
o
3f
o
4f
o
5f
o
6f
o
7f
o
FREQUENCY
Pin Description
PIN
1
2
3
4
NAME
IND
GND
TUNE
OUT-
FUNCTION
Tuning Inductor Port. Connect an inductor from IND to GND to set VCO center frequency (see
Oscillation
Frequency).
Ground. Connect to the ground plane with a low-inductance path.
Voltage-Control Input for Frequency Tuning. Input voltage range from +0.4V to +2.4V.
High-Impedance Open-Collector Output. An external pull-up resistor or inductor to V
CC
is required. Output
power is dependent on external load impedance. OUT- is complementary to OUT+.
Supply Voltage Connection. Connect an external bypass capacitor to ground for low noise and low spuri-
ous-output content. See
Layout Issues
for more details.
High-Impedance Open-Collector Output. An external pull-up resistor or inductor to V
CC
is required. Output
power is dependent on external load impedance. OUT+ is complementary to OUT-.
5
V
CC
6
OUT+
_______________________________________________________________________________________
5