Philips Semiconductors
SA602A
Double-balanced mixer and oscillator
Product specification
Replaces datasheet of April 17, 1990 1997 Nov 07
RF COMMUNICATIONS PRODUCTS
IC17 Data Handbook
Philips Semiconductors Product specification
SA602ADouble-balanced mixer and oscillator
2
1997 Nov 07 853-1424 18662
DESCRIPTION
The SA602A is a low-power VHF monolithic double-balanced mixer
with input amplifier, on-board oscillator, and voltage regulator . It is
intended for high performance, low power communication systems.
The guaranteed parameters of the SA602A make this device
particularly well suited for cellular radio applications. The mixer is a
“Gilbert cell” multiplier configuration which typically provides 18dB of
gain at 45MHz. The oscillator will operate to 200MHz. It can be
configured as a crystal oscillator, a tuned tank oscillator, or a buffer
for an external LO. For higher frequencies the LO input may be
externally driven. The noise figure at 45MHz is typically less than
5dB. The gain, intercept performance, low-power and noise
characteristics make the SA602A a superior choice for
high-performance battery operated equipment. It is available in an
8-lead dual in-line plastic package and an 8-lead SO (surface-mount
miniature package).
FEATURES
•Low current consumption: 2.4mA typical
•Excellent noise figure: <4.7dB typical at 45MHz
•High operating frequency
•Excellent gain, intercept and sensitivity
•Low external parts count; suitable for crystal/ceramic filters
•SA602A meets cellular radio specifications
PIN CONFIGURATION
INA
INB
GND
OUTA
VCC
OSCB
1
2
3
45
6
7
8
OSCE
OUTB
D and N Packages
SR00068
Figure 1. Pin Configuration
APPLICATIONS
•Cellular radio mixer/oscillator
•Portable radio
•VHF transceivers
•RF data links
•HF/VHF frequency conversion
•Instrumentation frequency conversion
•Broadband LANs
ORDERING INFORMATION
DESCRIPTION TEMPERATURE RANGE ORDER CODE DWG #
8-Pin Plastic Dual In-Line Plastic (DIP) -40 to +85°C SA602AN SOT97-1
8-Pin Plastic Small Outline (SO) package (Surface-mount) -40 to +85°C SA602AD SOT96-1
ABSOLUTE MAXIMUM RATINGS
SYMBOL PARAMETER RATING UNITS
VCC Maximum operating voltage 9 V
TSTG Storage temperature range -65 to +150 °C
TAOperating ambient temperature range SA602A -40 to +85 °C
θJA Thermal impedance D package 90 °C/W
N package 75 °C/W
Philips Semiconductors Product specification
SA602ADouble-balanced mixer and oscillator
1997 Nov 07 3
BLOCK DIAGRAM
8765
4321
OSCILLATOR
VOLTAGE
REGULATOR
GROUND
VCC
SR00069
Figure 2. Block Diagram
AC/DC ELECTRICAL CHARACTERISTICS
VCC = +6V, TA = 25°C; unless otherwise stated.
LIMITS
SYMBOL PARAMETER TEST CONDITIONS SA602A UNITS
MIN TYP MAX
VCC Power supply voltage range 4.5 8.0 V
DC current drain 2.4 2.8 mA
fIN Input signal frequency 500 MHz
fOSC Oscillator frequency 200 MHz
Noise figure at 45MHz 5.0 5.5 dB
Third-order intercept point RFIN = -45dBm: f1 = 45.0MHz
f2 = 45.06MHz -13 -15 dBm
Conversion gain at 45MHz 14 17 dB
RIN RF input resistance 1.5 kΩ
CIN RF input capacitance 3 3.5 pF
Mixer output resistance (Pin 4 or 5) 1.5 kΩ
DESCRIPTION OF OPERATION
The SA602A is a Gilbert cell, an oscillator/buffer, and a temperature
compensated bias network as shown in the equivalent circuit. The
Gilbert cell is a differential amplifier (Pins 1 and 2) which drives a
balanced switching cell. The differential input stage provides gain
and determines the noise figure and signal handling performance of
the system.
The SA602A is designed for optimum low power performance.
When used with the SA604 as a 45MHz cellular radio second IF and
demodulator, the SA602A is capable of receiving -119dBm signals
with a 12dB S/N ratio. Third-order intercept is typically -13dBm (that
is approximately +5dBm output intercept because of the RF gain).
The system designer must be cognizant of this large signal
limitation. When designing LANs or other closed systems where
transmission levels are high, and small-signal or signal-to-noise
issues are not critical, the input to the SA602A should be
appropriately scaled.
Besides excellent low power performance well into VHF, the
SA602A is designed to be flexible. The input, RF mixer output and
oscillator ports can support a variety of configurations provided the
designer understands certain constraints, which will be explained
here.
The RF inputs (Pins 1 and 2) are biased internally. They are
symmetrical. The equivalent AC input impedance is approximately
1.5k || 3pF through 50MHz. Pins 1 and 2 can be used
interchangeably, but they should not be DC biased externally .
Figure 5 shows three typical input configurations.
The mixer outputs (Pins 4 and 5) are also internally biased. Each
output is connected to the internal positive supply by a 1.5kΩ
resistor. This permits direct output termination yet allows for
balanced output as well. Figure 6 shows three single ended output
configurations and a balanced output.
Philips Semiconductors Product specification
SA602ADouble-balanced mixer and oscillator
1997 Nov 07 4
The oscillator is capable of sustaining oscillation beyond 200MHz in
crystal or tuned tank configurations. The upper limit of operation is
determined by tank “Q” and required drive levels. The higher the
“Q” of the tank or the smaller the required drive, the higher the
permissible oscillation frequency. If the required LO is beyond
oscillation limits, or the system calls for an external LO, the external
signal can be injected at Pin 6 through a DC blocking capacitor.
External LO should be at least 200mVP-P.
Figure 7 shows several proven oscillator circuits. Figure 7a is
appropriate for cellular radio. As shown, an overtone mode of
operation is utilized. Capacitor C3 and inductor L1 suppress
oscillation at the crystal fundamental frequency. In the fundamental
mode, the suppression network is omitted.
Figure 8 shows a Colpitts varactor tuned tank oscillator suitable for
synthesizer-controlled applications. It is important to buffer the
output of this circuit to assure that switching spikes from the first
counter or prescaler do not end up in the oscillator spectrum. The
dual-gate MOSFET provides optimum isolation with low current.
The FET offers good isolation, simplicity, and low current, while the
bipolar transistors provide the simple solution for non-critical
applications. The resistive divider in the emitter-follower circuit
should be chosen to provide the minimum input signal which will
assure correct system operation.
When operated above 100MHz, the oscillator may not start if the Q
of the tank is too low. A 22kΩ resistor from Pin 7 to ground will
increase the DC bias current of the oscillator transistor. This
improves the AC operating characteristic of the transistor and
should help the oscillator to start. A 22kΩ resistor will not upset the
other DC biasing internal to the device, but smaller resistance
values should be avoided.
8765
4321
OUTPUT
150pF
330pF
120pF
1.5 to
100nF
220pF
INPUT
47pF
22pF
1nF
100nF 10nF
VCC
6.8µF
5.5µH
0.209 to 0.283µH
44.2µH
10pF
34.545MHz THIRD OVERTONE CRYSTAL
602A
0.5 to 1.3µH
SR00070
Figure 3. Test Configuration
Philips Semiconductors Product specification
SA602ADouble-balanced mixer and oscillator
1997 Nov 07 5
12
3
45
6
7
8
GND
BUFFER 1.5k
BIAS BIAS
BIAS
1.5k
1.5k 1.5k
VCC
18k
25k
SR00071
Figure 4. Equivalent Circuit
INPUT
602A
12
602A
12
602A
12
a. Single-Ended Tuned Input b. Balanced Input (For Attenuation
of Second-Order Products) c. Single-Ended Untuned Input
SR00072
Figure 5. Input Configuration
Philips Semiconductors Product specification
SA602ADouble-balanced mixer and oscillator
1997 Nov 07 6
602A
4
5
602A
4
5
602A
4
5
602A
4
5
a. Single-Ended Ceramic Filter b. Single-Ended Crystal Filter
c. Single-Ended IFT d.. Balanced Output
SR00073
Figure 6. Output Configuration
602A
4
5
a. Colpitts Crystal Oscillator
(Overtone Mode) b. Colpitts L/C Tank Oscillator c. Hartley L/C Tank Oscillator
3
6
2
7
1
8
602A
4
5
3
6
2
7
1
8
602A
4
5
3
6
2
7
1
8
XTAL
L1
C1
C2
C3
SR00074
Figure 7. Oscillator Circuits
Philips Semiconductors Product specification
SA602ADouble-balanced mixer and oscillator
1997 Nov 07 7
602A
45
36
27
18
+6V
7pF 10pF
TO
BUFFER
DC CONTROL VOLTAGE
FROM SYNTHESIZER
MV2105
OR EQUIVALENT
1000pF
1000pF
5.5µH
0.10pF 10µF
0.06µH
0.1µF
3SK126
100k
2pF TO SYNTHESIZER
100k
100k
330
2k
TO SYNTHESIZER
2N5484
2N918
0.01µF
0.01µF
1.0nF
SR00075
Figure 8. Colpitts Oscillator Suitable for Synthesizer Applications and Typical Buffers
8765
4321 SFG455A3
100nF
220pF
INPUT
47pF
22pF
1nF
100nF 10nF
VCC
6.8µF
0.5 to 1.3µH
0.209 to 0.283µH
10pF
34.545MHz THIRD OVERTONE CRYSTAL
602A
OR EQUIVALENT
SR00076
Figure 9. Typical Application for Cellular Radio
Philips Semiconductors Product specification
SA602ADouble-balanced mixer and oscillator
1997 Nov 07 8
3.50
3.25
3.00
2.75
2.50
2.25
2.00
1.75
1.50
–40 –30 –20 –10 0 10 20 30 40 50 60 70 80 90
SUPPLY CURRENT 9mA)
TEMPERATURE OC
4.5V
6.0V
8.5V
SR00077
Figure 10. ICC vs Supply
Voltage
–40 –30 –20 –10 0 10 20 30 40 50 60 70 80 90
20.0
19.5
19.0
18.5
18.0
17.5
17.0
16.5
16.0
15.5
15.0
14.5
14.0
CONVERSION GAIN (dB)
TEMPERATURE OC
4.5V
6.0V
8.5V
SR00078
Figure 11. Conversion Gain vs Supply Voltage
–10.0
–10.5
–11.0
–11.5
–12.0
–12.5
–13.0
–13.5
–14.0
INPUT INTERCEPT POINT (dBm)
–14.5
–15.0
–15.5
–16.0
–16.5
–17.0
TEMPERATURE OC
–40 –30 –20 –10 0 10 20 30 40 50 60 70 80 90
SR00079
Figure 12. Third-Order Intercept Point
6.00
5.75
5.50
5.25
5.00
4.75
4.50
4.25
4.00
–40 –30 –20 –10 0 10 20 30 40 50 60 70 80 90
NOISE FIGURE (dB)
TEMPERATURE OC
4.5V
6.0V
8.5V
SR00080
Figure 13. Noise Figure
–80 –60 –40 –20 0 20
20
0
–20
–40
–60
3rd ORDER PRODUCT
FUND. PRODUCT
IF OUTPUT POWER (dBm)
RF INPUT LEVEL (dBm)
RF1 = 45MHz, IF = 455kHz, RF2 = 45.06MHz
SR00081
Figure 14. Third-Order Intercept and Compression
–10
–11
–12
–13
–14
–15
–16
–17
–18
45678 910
V
CC (VOLTS)
INTERCEPT (dBm)
SR00082
Figure 15. Input Third-Order Intermod Point vs VCC
Philips Semiconductors Product specification
SA602ADouble-balanced mixer and oscillator
1997 Nov 07 9
SO8: plastic small outline package; 8 leads; body width 3.9mm SOT96-1
Philips Semiconductors Product specification
SA602ADouble-balanced mixer and oscillator
1997 Nov 07 10
DIP8: plastic dual in-line package; 8 leads (300 mil) SOT97-1
Philips Semiconductors Product specification
SA602ADouble-balanced mixer and oscillator
1997 Nov 07 11
Philips Semiconductors and Philips Electronics North America Corporation reserve the right to make changes, without notice, in the products,
including circuits, standard cells, and/or software, described or contained herein in order to improve design and/or performance. Philips
Semiconductors assumes no responsibility or liability for the use of any of these products, conveys no license or title under any patent, copyright,
or mask work right to these products, and makes no representations or warranties that these products are free from patent, copyright, or mask
work right infringement, unless otherwise specified. Applications that are described herein for any of these products are for illustrative purposes
only. Philips Semiconductors makes no representation or warranty that such applications will be suitable for the specified use without further testing
or modification.
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This data sheet contains preliminary data, and supplementary data will be published at a later date. Philips
Semiconductors reserves the right to make changes at any time without notice in order to improve design
and supply the best possible product.
Philips Semiconductors
811 East Arques Avenue
P.O. Box 3409
Sunnyvale, California 94088–3409
Telephone 800-234-7381
DEFINITIONS
Data Sheet Identification Product Status Definition
Objective Specification
Preliminary Specification
Product Specification
Formative or in Design
Preproduction Product
Full Production
This data sheet contains the design target or goal specifications for product development. Specifications
may change in any manner without notice.
This data sheet contains Final Specifications. Philips Semiconductors reserves the right to make changes
at any time without notice, in order to improve design and supply the best possible product.
Copyright Philips Electronics North America Corporation 1997
All rights reserved. Printed in U.S.A.
