SA636
Low voltage high performance mixer FM
IF system with high-speed RSSI
Product data
Supersedes data of 1997 Nov 07 2003 Aug 01
INTEGRATED CIRCUITS
Philips Semiconductors Product specification
SA636
Low voltage high performance mixer FM
IF system with high-speed RSSI
2
2003 Aug 01
DESCRIPTION
The SA636 is a low-voltage high performance monolithic FM IF
system with high-speed RSSI incorporating a mixer/oscillator, two
limiting intermediate frequency amplifiers, quadrature detector ,
logarithmic received signal strength indicator (RSSI), voltage
regulator, wideband data output and fast RSSI op amps. The SA636
is available in 20-lead SSOP (shrink small outline package).
The SA636 was designed for high bandwidth portable
communication applications and will function down to 2.7 V. The RF
section is similar to the famous SA605. The data output has a
minimum bandwidth of 600 kHz. This is designed to demodulate
wideband data. The RSSI output is amplified. The RSSI output has
access to the feedback pin. This enables the designer to adjust the
level of the outputs or add filtering.
SA636 incorporates a power-down mode which powers down the
device when Pin 8 is LOW. Power down logic levels are CMOS and
TTL compatible with high input impedance.
FEATURES
•Wideband data output (600 kHz min.)
•Fast RSSI rise and fall times
•Low power consumption: 6.5 mA typ. at 3 V
•Mixer input to >500 MHz
•Mixer conversion power gain of 11 dB at 240 MHz
•Mixer noise figure of 12 dB at 240 MHz
•XTAL oscillator effective to 150 MHz (L.C. oscillator to 1 GHz local
oscillator can be injected)
•92 dB of IF Amp/Limiter gain
•25 MHz limiter small signal bandwidth
•Temperature compensated logarithmic Received Signal Strength
Indicator (RSSI) with a dynamic range in excess of 90 dB
•RSSI output internal op amp
•Internal op amps with rail-to-rail outputs
•Low external component count; suitable for crystal/ceramic/LC
filters
•Excellent sensitivity: 0.54 µV into 50 Ω matching network for
12 dB SINAD (Signal to Noise and Distortion ratio) for 1 kHz tone
with RF at 240 MHz and IF at 10.7 MHz
•ESD hardened
•10.7 MHz filter matching (330 Ω)
•Power-down mode (ICC = 200 µA)
PIN CONFIGURATION
RFIN
RF BYPASS
RSSIOUT
MIXER OUT
IF AMP IN
IF AMP OUT
GND
LIMITER IN
LIMITER OUT
DK Package
POWER DOWN CONTROL
DATA OUT
QUADRATURE IN
IF AMP DECOUPLING
IF AMP DECOUPLING
LIMITER DECOUPLING
LIMITER DECOUPLING
VCC
RSSI FEEDBACK
XTAL OSC (EMITTER)
XTAL OSC (BASE)
1
2
3
4
5
6
7
8
9
10
20
19
18
17
16
15
14
13
12
11
SR00491
Figure 1. Pin configuration
APPLICATIONS
•DECT (Digital European Cordless Telephone)
•Digital cordless telephones
•Digital cellular telephones
•Portable high performance communications receivers
•Single conversion VHF/UHF receivers
•FSK and ASK data receivers
•Wireless LANs
ORDERING INFORMATION
DESCRIPTION TEMPERATURE RANGE ORDER CODE DWG #
20-Pin Plastic Shrink Small Outline Package (Surface-mount) –40 °C to +85 °C SA636DK SOT266–1
Philips Semiconductors Product specification
SA636
Low voltage high performance mixer FM
IF system with high-speed RSSI
2003 Aug 01 3
BLOCK DIAGRAM
20 19 18 17 16 15 14 13 12 11
10987654321
FAST
IF
AMP
EB
OSCILLATOR
LIMITER
MIXER
QUAD
+– +–
RSSI
GND
PWR
DWN
RSSI AUDIO
VCC
SR00492
Figure 2. Block diagram
ABSOLUTE MAXIMUM RATINGS
SYMBOL PARAMETER RATING UNITS
VCC Single supply voltage 0.3 to 7 V
VIN Voltage applied to any other pin –0.3 to (VCC+0.3) V
Tstg Storage temperature range –65 to +150 °C
Tamb Operating ambient temperature range SA636 –40 to +85 °C
θJA Thermal impedance (DC package) 117 °C/W
DC ELECTRICAL CHARACTERISTICS
VCC = +3 V, Tamb = 25 °C; unless otherwise stated.
SYMBOL
PARAMETER
TEST CONDITIONS
LIMITS
UNITS
SYMBOL
PARAMETER
TEST
CONDITIONS
MIN TYP MAX
UNITS
VCC Power supply voltage range 2.7 3.0 5.5 V
ICC DC current drain Pin 8 = HIGH 5.5 6.5 7.5 mA
In
p
ut current
Pin 8 LOW –10 10 µA
Inp
u
t
c
u
rrent
Pin 8 HIGH –10 10 µA
In
p
ut level
Pin 8 LOW 0 0.3VCC V
Inp
u
t
le
v
el
Pin 8 HIGH 0.7VCC VCC V
ICC Standby Pin 8 = LOW 0.2 0.5 mA
tON Power-up time RSSI valid (10% to 90%) 10 µs
tOFF Power-down time RSSI invalid (90% to 10%) 5µs
Philips Semiconductors Product specification
SA636
Low voltage high performance mixer FM
IF system with high-speed RSSI
2003 Aug 01 4
AC ELECTRICAL CHARACTERISTICS
Tamb = 25 °C; VCC = +3V, unless otherwise stated. RF frequency = 240.05 MHz + 14.5 dBV RF input step-up; IF frequency = 10.7 MHz;
RF level = –45 dBm; FM modulation = 1 kHz with ±125 kHz peak deviation. Audio output with C-message weighted filter and de-emphasis
capacitor. Test circuit Figure 1. The parameters listed below are tested using automatic test equipment to assure consistent electrical
characteristics. The limits do not represent the ultimate performance limits of the device. Use of an optimized RF layout will improve many of the
listed parameters.
SYMBOL
PARAMETER
TEST CONDITIONS
LIMITS
UNITS
SYMBOL
PARAMETER
TEST
CONDITIONS
MIN TYP MAX
UNITS
Mixer/Osc section (ext LO = 160mVRMS)
fIN Input signal frequency 500 MHz
fOSC External oscillator (buffer) 500 MHz
Noise figure at 240 MHz 12 dB
Third-order input intercept point Matched f1=240.05 MHz; f2=240.35 MHz –16 dBm
Conversion power gain Matched 14.5 dBV step-up 811 14 dB
RF input resistance Single-ended input 700 Ω
RF input capacitance 3.5 pF
Mixer output resistance (Pin 20) 330 Ω
IF section
IF amp gain 330 Ω load 38 dB
Limiter gain 330 Ω load 54 dB
Input limiting –3dB Test at Pin 18 –105 dBm
AM rejection 80% AM 1 kHz 50 dB
Data level RLOAD = 100 kΩ120 130 mVRMS
3 dB data bandwidth 600 700 kHz
SINAD sensitivity RF level = –111 dBm 16 dB
THD Total harmonic distortion –43 –38 dB
S/N Signal-to-noise ratio No modulation for noise 60 dB
IF level = –118 dBm 0.2 0.5 V
IF RSSI output with buffer IF level = –68 dBm 0.3 0.6 1.0 V
IF level = –10d Bm 0.9 1.3 1.8 V
IF RSSI output rise time IF frequency = 10.7 MHz
(10kHz pulse, no 10.7MHz filter) RF level = –56 dBm 1.2 µs
(no RSSI bypass capacitor) RF level = –28 dBm 1.1 µs
IF RSSI output fall time IF frequency = 10.7 MHz
(10 kHz pulse, no 10.7 MHz filter) RF level = –56 dBm 2.0 µs
(no RSSI bypass capacitor) RF level = –28 dBm 7.3 µs
RSSI range 90 dB
RSSI accuracy ±1.5 dB
IF input impedance 330 Ω
IF output impedance 330 Ω
Limiter input impedance 330 Ω
Limiter output impedance 300 Ω
Limiter output level with no load 130 mVRMS
RF/IF section (int LO)
System RSSI output RF level = –10 dBm 1.4 V
System SINAD RF level = –106 dBm 12 dB
Philips Semiconductors Product specification
SA636
Low voltage high performance mixer FM
IF system with high-speed RSSI
2003 Aug 01 5
PERFORMANCE CHARACTERISTICS
0.50
0.45
0.40
0.35
0.30
0.25
0.20
0.15
0.10
0.05
0.00
POWER DOWN SUPPLY CURRENT (mA)
–50–40 –30 –20 –10 0 10 20 30 40 50 60 70 80 90
TEMPERATURE (°C) 100
Power Down Supply Current vs Temperature and Supply Voltage
VCC = 5V
VCC = 3V
VCC = 2.7V
9.0
8.5
8.0
7.5
7.0
6.5
6.0
5.5
5.0
SUPPLY CURRENT (mA)
–50 –40 –30 –20 –10 0 10 20 30 40 50 60 70 80 90
TEMPERATURE (°C)
Supply Current vs Temperature and Supply Voltage
Mixer Power Gain vs Temperature and Supply Voltage 20
0
–20
–40
–60
–80
–100
–120
AUDIO (dB)
–50–40 –30 –20 –10 0 10 20 30 40 50 60 70 80 90
TEMPERATURE (°C)
12dB SINAD and Relative Audio, THD, Noise
and AM Rejection for VCC = 3V vs Temperature
RF = 240MHz, Level = –68dBm, Deviation = 125kHz
VCC = 3V
VCC = 2.7V
VCC = 5V
AUDIO
AM REJECTION
DISTORTION
NOISE
12dB SINAD
MIXER GAIN
(dB)
Temperature (°C)
–40 0 25 70 85
20
19
18
17
16
15
14
13
12
11
10
9
8
7
6
5
5.5V
2.7V
3.0V
RF level = -45 dBm
Mixer IIP3 at 240MHz vs Temperature and Supply Voltage
Temperature (°C)
–40 0 25 70 85
MIXER IIP3 (deB)
–5
–7
–9
–11
–13
–15
–17
–19
–21
–23
–25
5.5V 2.7V
3.0V
RF level = -45 dBm
Temperature (°C)
–40 0257085
300
AUDIO REFERENCE (mVrms)
5.5V
2.7V
3.0V
250
200
150
100
50
0
Audio Reference Level vs Temperature and Supply Voltage
SR00493
Figure 3. Performance Characteristics
Philips Semiconductors Product specification
SA636
Low voltage high performance mixer FM
IF system with high-speed RSSI
2003 Aug 01 6
PERFORMANCE CHARACTERISTICS (continued)
10
0
–10
–20
–30
–40
–50
–60
–70
–80
–90
2
1.8
1.6
1.4
1.3
1.0
0.8
0.6
0.4
0.2
0
RSSI (V)
RELATIVE TO AUDIO OUTPUT (dB)
RF INPUT LEVEL (dBm)
Receiver RF Performance — T = 25°C,
Audio Level = 129mVRMS
10
0
–10
–20
–30
–40
–50
–60
–70
–80
–90
2.0
1.8
1.6
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0.0
RSSI (V)
RELATIVE TO AUDIO OUTPUT (dB)
RF INPUT LEVEL (dBm)
AUDIO
AM REJECTION
THD+N
NOISE
RSSI
Receiver RF Performance — T = –40°C,
Audio Level = 118mVRMS
0
–10
–20
–30
–40
–50
–60
–70
–80
–90
–100
–110
–65
–60
–55
–50
–45
–40
–35
–30
–25
–20
–15
–10
RF INPUT POWER (dBm)
IF OUTPUT POWER (dBm)
Mixer Third Order Intercept and Compression
RF INPUT LEVEL (dBm)
RSSI (V)
RSSI vs RF Input Level and Temperature
–40°C
25°C
85°C
10
0
–10
–20
–30
–40
–50
–60
–70
–80
–90
–110
–100
–90
–80
–70
–60
–50
–40
–30
–20
–10
0
2
1.8
1.6
1.4
1.2
1
0.8
0.6
0.4
0.2
0
RSSI (V)
RELATIVE TO AUDIO OUTPUT (dB)
Receiver RF Performance – T = 85°C, Audio Level = 131mVRMS
AUDIO
AM REJECTION
THD+N
NOISE
RSSI
AUDIO
AM REJECTION
THD+N
NOISE
RSSI
–110
–100
–90
–80
–70
–60
–50
–40
–30
–20
–10
0
–110
–100
–90
–80
–70
–60
–50
–40
–30
–20
–10
0
–110
–100
–90
–80
–70
–60
–50
–40
–30
–20
–10
0
2
1.8
1.6
1.4
1.2
1
0.8
0.6
0.4
0.2
0
Temperature (°C)
–40 0 25 70
85
–5
–7
–9
–11
–13
–15
–17
–19
–21
–23
–25
MIXER IIP3 (dB)
5.5V 2.7V
3.0V
RF level = -45 dBm
Mixer IIP3 at 240MHz vs Temperature and Supply Voltage
SR00494
Figure 4. Performance Characteristics
Philips Semiconductors Product specification
SA636
Low voltage high performance mixer FM
IF system with high-speed RSSI
2003 Aug 01 7
PERFORMANCE CHARACTERISTICS (continued)
50.00
48.00
46.00
44.00
42.00
40.00
38.00
36.00
34.00
32.00
30.00
–50.00
–30.00
–10.00
10.00
30.00
50.00
70.00
90.00
POWER GAIN (dB)
TEMPERATURE (°C)
65.00
63.00
61.00
59.00
57.00
55.00
53.00
51.00
49.00
47.00
45.00
POWER GAIN (dB)
TEMPERATURE (°C)
–50.00
–30.00
–10.00
10.00
30.00
50.00
70.00
90.00
SA626 IF Amplifier Gain vs Temperature vs Supply Voltage SA626 Limiting Amplifier Gain vs Temperature vs Supply Voltage
VCC = 3V
VCC = 2.7V
VCC = 5V
VCC = 3V
VCC = 2.7V
VCC = 5V
Data Level vs Temperature and Supply Voltage
DATA LEVEL (Vp-p)
Temperature (°C)
–40 0 25 70 85
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
5.5V
2.7V
3.0V
600kHz Data Rate,
IF = 9.85MHz,
Dev = 288kHz,
RF = -40dBm
Data Level vs Temperature and Supply Voltage
Temperature (°C)
–40 0257085
DATA LEVEL (Vp-p)
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
5.5V
2.7V
3.0V
1kHz Data Rate,
IF = 9.85MHz,
Dev = 288kHz,
RF = -40dBm
SR00495
Figure 5. Performance Characteristics
Philips Semiconductors Product specification
SA636
Low voltage high performance mixer FM
IF system with high-speed RSSI
2003 Aug 01 8
PERFORMANCE CHARACTERISTICS (continued)
Temperature (°C)
300
AUDIO REFERENCE (mVrms)
5.5V
2.7V
3.0V
–40 0257085
250
200
150
100
50
0
Audio Reference Level vs Temperature and Supply Voltage Temperature (°C)
0.8
DATA LEVEL (Vp-p)
5.5V
2.7V
3.0V
600kHz Data Rate,
Data Level vs Temperature and Supply Voltage
–40 0257085
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
IF = 9.85MHz,
Dev = 288kHz,
RF = -40dBm
5.5V
2.7V
3.0V
1kHz Data Rate,
IF = 9.85MHz,
Dev = 288kHz,
RF = -40dBm
0.8
DATA LEVEL (Vp-p)
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
Temperature (°C)
Data Level vs Temperature and Supply Voltage
–40 0257085
SR00496
Figure 6. Performance Characteristics
Philips Semiconductors Product specification
SA636
Low voltage high performance mixer FM
IF system with high-speed RSSI
2003 Aug 01 9
PIN FUNCTIONS
1
0.8k
2
0.8k
4
3
18k
MIX
150µA
5VREF
BANDGAP
10
80k
20µA
6+
VCC
—
7
VCC
+
—
8
R
R
PIN
No. PIN
MNEMONIC DC V EQUIVALENT CIRCUIT PIN
No. PIN
MNEMONIC DC V EQUIVALENT CIRCUIT
9
+
—
VCC
1 RF IN +1.07 6 RSSI +0.20
FEEDBACK
2RF +1.07 7 RSSI +0.20
OUTBYPASS
3XTAL +1.57 8 POWER +2.75
DOWNOSC
4XTAL +2.32 9 DATA +1.09
OUTOSC
5V
CC +3.00 10 QUAD. +3.00
IN
SR00497
Figure 7. Pin Functions
Philips Semiconductors Product specification
SA636
Low voltage high performance mixer FM
IF system with high-speed RSSI
2003 Aug 01 10
PIN FUNCTIONS (continued)
11
14
20
400µA
PIN
No. PIN
MNEMONIC DC V EQUIVALENT CIRCUIT PIN
No. PIN
MNEMONIC DC V EQUIVALENT CIRCUIT
11 LIMITER +1.35 16 IF +1.22
AMP OUT
12 LIMITER +1.23 17 IF AMP +1.22
DECOUPDECOUP
13 LIMITER +1.23 18 IF +1.22
AMP INCOUPLING
14 LIMITER +1.23 19 IF AMP +1.22
DECOUPIN
15 GND 0 20 MIXER +1.03
OUT
OUT
8.8k
16
8.8k
140Ω
13
12
330Ω
50µA
18
19
17
330Ω
50µA
110Ω
SR00498
Figure 8. Pin Functions (cont.)
Philips Semiconductors Product specification
SA636
Low voltage high performance mixer FM
IF system with high-speed RSSI
2003 Aug 01 11
10987654321
20 19 18 17 16 15 14 13 12 11
RSSI
MIXER
QUAD
C19
C18 SW5
C13 C15
FLT1
0.1µF
6.8µF 10V
160pF select
1000pF
39pF select
0.1µF
1µF
C14
C15
C18
C19
C20
C21
L1
L2
L3
L4
L5
FLT1
0.1µF
1000pF
10.7MHz (Murata SFE10.7MA5-A)
1.27–2.25µH select for mixer
5.6µH select for input match
22nH select for input match
1000pF
C1
C2
C3
C4
C5
C6
*C7
C8
C9
C10
C11
C12
C13
Automatic Test Circuit Component List
OSCILLATOR
FLT2 10.7MHz (Murata SFE10.7MA5-A)
FLT3 Active de-emphasis
FLT4 “C” message weighted
LIMITER
VCC +
–
DATA
C16 0.1µF
C17 0.1µF
*NOTE: This value can be reduced when a battery is the power source.
PWR
DWN
0.1µF
100pF
1–5pF select for input match
0.1µF
0.1µF
1–5pF select for input match 47nH select for input match
0.1µF
1000pF
150nH select for input match
1pF
FLT
3
FLT
4
FLT2
R1
R2
R3
R4
R5
R6
R7
R8
R9
R10
R11
347.8Ω
6.42kΩ
49.9Ω
1kΩ
347.8Ω
49.9Ω
49.9Ω
1kΩ
49.9Ω
8.2kΩ select
6.42kΩ
MIXER
IF/LIM OUT IF/LIM IN
L5
C12
C11
21
+
–
IF
AMP
21
C14
R3
R2
R4
R5
C16 R6
21 21
C17
R8
R7
R9
C20
R10
R11
C21
L4
R1
C8
C9
C10
C6
C7
C4
C5
L3
C3C1
*L1
*L2
RF IN LO IN
RSSI
OUT
PWR
DWN
CTRL DATA
OUT
VCC
output match
C2
SR00501
Figure 9. SA636 240.05MHz (RF) / 10.7MHz (IF) Test Circuit
Philips Semiconductors Product specification
SA636
Low voltage high performance mixer FM
IF system with high-speed RSSI
2003 Aug 01 12
10
9
8
7
6
5
4
3
2
120
19
18
17
16
15
14
13
12
11
RF IN
RF BYPASS
OSC (EMITTER)
OSC (BASE)
RSSI FEEDBACK
RSSI OUT
PD CTRL
DATA OUT
QUAD IN
VCC
MIXER OUT
DECOUPLING 1
IF IN
DECOUPLING 2
GROUND
LIMITER IN
LIMITER DEC1
LIMITER DEC2
LIMITER OUT
IF OUT
SMA
LO IN
SMA
RF IN
110.592MHz
120.392MHz
C5 C6
+
R1
51
C3
1nF
C2
PWR DWN
VCC
L1
180nH
C1
5–30pF
U1
SA636
R5
1.2k C9
82pF
L2
C10
15pF
C11 C12
10nF
100nF 1nF 1nF
15µF
2.2µH
XTAL
XTAL
IF AMP
IF AMP
J1
+/–288kHz
J2 @–10dBm
C4
1nF
R2
10
+3V
R3
22k
R4
33k
RSSI
DATA OUT
GND
J3
C7
470pF
C8 +
5-30pF
C13
100pF
C14
47pF
C15
330pF
L3
680nH
R6
560
C16
100pF
C17
1nF
C19
1nF
L4
680nH
C21
330pF
C18
68pF
C20
68pF
SR00500
Figure 10. SA636 110.592 MHz (RF) / 9.8 MHz (IF) DECT Application Circuit
Philips Semiconductors Product specification
SA636
Low voltage high performance mixer FM
IF system with high-speed RSSI
2003 Aug 01 13
Table 1. DECT Application Circuit Electrical Characteristics
RF frequency = 110.592 MHz; IF frequency = 9.8 MHz; RF level = –45 dBm; FM modulation = 100 kHz with ±288 kHz peak deviation.
SYMBOL PARAMETER TEST CONDITIONS TYPICAL UNITS
Mixer/Osc section (ext LO = 160 mVRMS)
PG Conversion power gain 13 dB
NF Noise Figure at 110 MHz 12 dB
IIP3 Third order input intercept Matched f1 = 110.592 MHz; f2 = 110.892 MHz –15 dBm
RIN RF input resistance 690 Ω
CIN RF input capacitance 3.6 pF
IF section
IF amp gain 330 Ω load 38 dB
Limiter amp gain 330 Ω load 54 dB
Data level RLOAD = 3 kΩ130 mVRMS
3 dB data bandwidth 700 kHz
RF/IF section (internal LO)
System RSSI output RF level = –10 dBm 1.4 V
System S/N1RF level = –83 dBm 10 dB
NOTE:
1. 10 dB S/N corresponds to BER = 10–3.
RF GENERATOR
SPECTRUM
ANALYZER
SCOPE
DC VOLTMETER
110.592MHz RSSI DATA
SA636 DEMO BOARD
LO / GENERATOR
120.392MHz
VCC = 3V
SR00502
Figure 11. SA636 Application Circuit Test Set Up
NOTES:
1. RF generator: Set your RF generator at 110.592 MHz, use a 100 kHz modulation frequency and a ±288 kHz deviation.
2. Layout: The layout is very critical in the performance of the receiver. We highly recommend our demo board layout.
3. RSSI: The smallest RSSI voltage (i.e., when no RF input is present and the input is terminated) is a measure of the quality of the layout and
design. If the lowest RSSI voltage is 500 mV or higher, it means the receiver is in regenerative mode. In that case, the receiver sensitivity
will be worse than expected.
4. Supply bypass and shielding: All of the inductors, the quad tank, and their shield must be grounded. A 0.1 µF bypass capacitor on the supply
pin improves sensitivity.
Philips Semiconductors Product specification
SA636
Low voltage high performance mixer FM
IF system with high-speed RSSI
2003 Aug 01 14
TOP SILK SCREEN (SSOP)
SR00503
Figure 12. SA636 Demoboard Layout (Not Actual Size)
Philips Semiconductors Product specification
SA636
Low voltage high performance mixer FM
IF system with high-speed RSSI
2003 Aug 01 15
CIRCUIT DESCRIPTION
The SA636 is an IF signal processing system suitable for second IF
or single conversion systems with input frequency as high as 1 GHz.
The bandwidth of the IF amplifier is about 40 MHz, with 38 dB of
gain from a 50 Ω source. The bandwidth of the limiter is about
28 MHz with about 54 dB of gain from a 50 Ω source. However, the
gain/bandwidth distribution is optimized for 10.7 MHz, 330 Ω source
applications. The overall system is well-suited to battery operation
as well as high performance and high quality products of all types,
such as cordless and cellular hand-held phones.
The input stage is a Gilbert cell mixer with oscillator. Typical mixer
characteristics include a noise figure of 14 dB, conversion gain of
11 dB, and input third-order intercept of –16 dBm. The oscillator will
operate in excess of 1 GHz in L/C tank configurations. Hartley or
Colpitts circuits can be used up to 100 MHz for xtal configurations.
Butler oscillators are recommended for xtal configurations up to
150 MHz.
The output of the mixer is internally loaded with a 330 Ω resistor
permitting direct connection to a 10.7 MHz ceramic filter for
narrowband applications. The input resistance of the limiting IF
amplifiers is also 330 Ω. With most 10.7 MHz ceramic filters and
many crystal filters, no impedance matching network is necessary.
For applications requiring wideband IF filtering, such as DECT,
external LC filters are used (see Figure 10). To achieve optimum
linearity of the log signal strength indicator, there must be a 6 dB(v)
insertion loss between the first and second IF stages. If the IF filter
or interstage network does not cause 6 dB(v) insertion loss, a fixed
or variable resistor can be added between the first IF output (Pin 16)
and the interstage network.
The signal from the second limiting amplifier goes to a Gilbert cell
quadrature detector. One port of the Gilbert cell is internally driven
by the IF. The other output of the IF is AC-coupled to a tuned
quadrature network. This signal, which now has a 90° phase
relationship to the internal signal, drives the other port of the
multiplier cell.
Overall, the IF section has a gain of 90 dB. For operation at
intermediate frequency at 10.7 MHz. Special care must be given to
layout, termination, and interstage loss to avoid instability.
The demodulated output (DATA) of the quadrature is a voltage
output. This output is designed to handle a minimum bandwidth of
600 kHz. This is designed to demodulate wideband data, such as in
DECT applications.
A Receive Signal Strength Indicator (RSSI) completes the circuitry.
The output range is greater than 90 dB and is temperature
compensated. This log signal strength indicator exceeds the criteria
for AMPS or TACS cellular telephone, DECT and RCR-28 cordless
telephone. This signal drives an internal op amp. The op amp is
capable of rail-to-rail output. It can be used for gain, filtering, or
2nd-order temperature compensation of the RSSI, if needed.
NOTE: dB(v) = 20log VOUT/VIN
Philips Semiconductors Product specification
SA636
Low voltage high performance mixer FM
IF system with high-speed RSSI
2003 Aug 01 16
SSOP20: plastic shrink small outline package; 20 leads; body width 4.4 mm SOT266-1
Philips Semiconductors Product specification
SA636
Low voltage high performance mixer FM
IF system with high-speed RSSI
2003 Aug 01 17
REVISION HISTORY
Rev Date Description
_2 20030801 Product data (9397 750 11848). ECN 853-1757 30101 of 15 July 2003.
Supersedes data of 1997 Nov 07.
Modifications:
•Change package outline drawing to SOT266-1.
_1 19971107 Product data. ECN 853-1757 18664 of 07 November 1997. Replaces data of 1994 Jun 16
Definitions
Short-form specification — The data in a short-form specification is extracted from a full data sheet with the same type number and title. For detailed information see
the relevant data sheet or data handbook.
Limiting values definition — Limiting values given are in accordance with the Absolute Maximum Rating System (IEC 60134). Stress above one or more of the limiting
values may cause permanent damage to the device. These are stress ratings only and operation of the device at these or at any other conditions above those given
in the Characteristics sections of the specification is not implied. Exposure to limiting values for extended periods may affect device reliability.
Application information — Applications that are described herein for any of these products are for illustrative purposes only. Philips Semiconductors make no
representation or warranty that such applications will be suitable for the specified use without further testing or modification.
Disclaimers
Life support — These products are not designed for use in life support appliances, devices, or systems where malfunction of these products can reasonably be
expected to result in personal injury. Philips Semiconductors customers using or selling these products for use in such applications do so at their own risk and agree
to fully indemnify Philips Semiconductors for any damages resulting from such application.
Right to make changes — Philips Semiconductors reserves the right to make changes in the products—including circuits, standard cells, and/or software—described
or contained herein in order to improve design and/or performance. When the product is in full production (status ‘Production’), relevant changes will be communicated
via a Customer Product/Process Change Notification (CPCN). 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.
Contact information
For additional information please visit
http://www.semiconductors.philips.com. Fax: +31 40 27 24825
For sales offices addresses send e-mail to:
sales.addresses@www.semiconductors.philips.com.
Koninklijke Philips Electronics N.V. 2003
All rights reserved. Printed in U.S.A.
Date of release: 08-03
Document order number: 9397 750 11848
Data sheet status[1]
Objective data
Preliminary data
Product data
Product
status[2] [3]
Development
Qualification
Production
Definitions
This data sheet contains data from the objective specification for product development.
Philips Semiconductors reserves the right to change the specification in any manner without notice.
This data sheet contains data from the preliminary specification. Supplementary data will be published
at a later date. Philips Semiconductors reserves the right to change the specification without notice, in
order to improve the design and supply the best possible product.
This data sheet contains data from the product specification. Philips Semiconductors reserves the
right to make changes at any time in order to improve the design, manufacturing and supply. Relevant
changes will be communicated via a Customer Product/Process Change Notification (CPCN).
Data sheet status
[1] Please consult the most recently issued data sheet before initiating or completing a design.
[2] The product status of the device(s) described in this data sheet may have changed since this data sheet was published. The latest information is available on the Internet at URL
http://www.semiconductors.philips.com.
[3] For data sheets describing multiple type numbers, the highest-level product status determines the data sheet status.
Level
I
II
III
