Philips Semiconductors RF Communications Products Product specification Low voltage high performance mixer FM IF system DESCRIPTION The SA608 is a low voltage high performance monolithic FM IF system incorporating a mixer/oscillator, two limiting intermediate frequency amplifiers, quadrature detector, logarithmic received signal strength indicator (RSSI), voltage regulator and audio and RSSI op amps. The SA608 is available in 20-lead dual-in-line plastic, 20-lead SOL (surface-mounted miniature package) and 20-lead SSOP package. The SA608 was designed for portable communication applications and will function down to 2.7V. The RF section is similar to the famous NE605. The audio output is buffered. The RSSI output has an internal amplifier with the feedback pin accessible. The SA608 also has an extra limiter output. This signal is buffered from the output of the limiter and can be used to perform frequency check. This is accomplished by comparing a reference frequency with the frequency check signal using a comparator to a varactor or PLL at the oscillator inputs. PIN CONFIGURATION crystal/ceramic/LC filters • Excellent sensitivity: 0.31µV into 50Ω matching network for 12dB SINAD (Signal to Noise and Distortion ratio) for 1kHz tone, 8kHz deviation with RF at 45MHz and IF at 455kHz • SA608 meets cellular radio specifications • Audio output internal op amp • RSSI output internal op amp • Buffered frequency check output • Internal op amps with rail-to-rail outputs • ESD protection: Human Body Model 2kV Robot Model 200V D, DK and N Packages RF IN+ 1 RF IN– 2 DECOUPLING 20 MIXER OUT 19 IF AMP DECOUPLING OSC- 3 18 IF AMP IN OUT OSC IN 4 17 IF AMP DECOUPLING RSSI 5 16 IF AMP OUT VCC 6 15 GND AUDIO 7 14 LIMITER IN RSSI 8 FEEDBACK FREQ CHECK/ 9 LIM OUT (–) QUADRATURE 10 IN 13 LIMITER DECOUPLING 12 LIMITER DECOUPLING 11 LIMITER OUT (+) APPLICATIONS • Portable cellular radio FM IF • Cordless phones • Narrow band cellular applications (NAMPS/NTACS) FEATURES • Low power consumption: • Low external component count; suitable for SA608 3.5mA typical at 3V • Mixer input to >150MHz • Mixer conversion power gain of 17dB at 45MHz • XTAL oscillator effective to 150MHz (L.C. oscillator or external oscillator can be used at higher frequencies) • 102dB of IF Amp/Limiter gain • 2MHz limiter small signal bandwidth • Temperature compensated logarithmic • RF level meter • Spectrum analyzer • Instrumentation • FSK and ASK data receivers • Log amps • Portable high performance communication receivers • Single conversion VHF receivers • Wireless systems Received Signal Strength Indicator (RSSI) with a 90dB dynamic range ORDERING INFORMATION DESCRIPTION TEMPERATURE RANGE ORDER CODE 20-Pin Plastic Dual In-Line Package (DIP) -40 to +85°C SA608N 0408B 20-Pin Plastic Small Outline Large (SOL) package (Surface-mount) -40 to +85°C SA608D 0172D 20-Pin Plastic Shrink Small Outline Package (SSOP) (Surface-mount) -40 to +85°C SA608DK 1563 November 3, 1992 2 DWG # 853-1679 08108 Philips Semiconductors RF Communications Products Product specification Low voltage high performance mixer FM IF system SA608 BLOCK DIAGRAM 20 19 18 17 16 15 14 13 IF AMP 12 11 9 10 LIMITER RSSI MIXER QUAD OSCILLATOR – + – + VREG 1 2 E B 3 4 AUDIO 5 6 7 8 ABSOLUTE MAXIMUM RATINGS SYMBOL PARAMETER RATING UNITS 7 V VCC Single supply voltage TSTG Storage temperature range –65 to +150 °C Operating ambient temperature range SA608 –40 to +85 °C 90 117 75 °C/W TA θJA Thermal impedance D package DK package N package DC ELECTRICAL CHARACTERISTICS VCC = +3V, TA = 25°C; unless otherwise stated. LIMITS SYMBOL PARAMETER TEST CONDITIONS SA608 MIN VCC Power supply voltage range ICC DC current drain November 3, 1992 TYP 2.7 3.5 3 UNITS MAX 7.0 V 4.2 mA Philips Semiconductors RF Communications Products Product specification Low voltage high performance mixer FM IF system SA608 AC ELECTRICAL CHARACTERISTICS TA = 25°C; VCC = +3V, unless otherwise stated. RF frequency = 45MHz + 14.5dBV RF input step-up; IF frequency = 455kHz; R17 = 2.4k; R18 = 3.3k; RF level = –45dBm; FM modulation = 1kHz with ±8kHz peak deviation. Audio output with de-emphasis filter and C-message weighted filter. Test circuit 1. The parameters listed below are tested using automatic test equipment to assure consistent electrical characterristics. 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. LIMITS SYMBOL PARAMETER TEST CONDITIONS SA608 MIN TYP UNITS MAX Mixer/Osc section (ext LO = 220mVRMS) fIN fOSC Input signal frequency 150 MHz Crystal oscillator frequency 150 MHz Noise figure at 45MHz 6.2 dB –9 dBm Third–order input intercept point (50Ω source) f1 = 45.0; f2 = 45.06MHz Input RF Level = –52dBm Conversion power gain Matched 14.5dBV step–up 13.5 50Ω source RF input resistance Single–ended input RF input capacitance 17 (Pin 20) 1.25 IF amp gain Limiter gain Input limiting –3dB, R17 = 2.4k Test at Pin 18 AM rejection 80% AM 1kHz dB +2.5 dB 8 kΩ 3.0 Mixer output resistance 19.5 4.0 pF 1.5 kΩ 50Ω source 44 dB 50Ω source 58 dB –109 dBm IF section Audio level2 SINAD sensitivity 45 dB 35 60 17 dB –35 –50 dB RF level –110dB 80 mV THD Total harmonic distortion S/N Signal–to–noise ratio No modulation for noise 62 IF RSSI output, R9 = 2kΩ1 IF level = –118dBm 0.3 0.8 V V dB IF level = –68dBm .70 1.1 1.80 IF level = –23dBm 1.2 1.8 2.5 RSSI range 90 RSSI accuracy V dB +1.5 dB 1.5 kΩ 0.3 kΩ 1.5 kΩ 200 Ω 130 115 mVRMS 200 Ω no load 5kΩ load 130 115 mVRMS Audio level 3V = VCC, RF level = –27dBm 120 mVRMS System RSSI output 3V = VCC, RF level = –27dBm 2.2 V System SINAD sensitivity RF level = –117dBm 12 dB IF input impedance 1.3 IF output impedance Limiter input impedance Limiter output impedance Limiter output level Frequency check/lim (–) output impedance Frequency check/lim (–) output level 1.30 (Pin 11) (Pin 11) no load 5kΩ load (Pin 9) (Pin 9) RF/IF section (int LO) NOTE: 1. The generator source impedance is 50Ω, but the SA608 input impedance at Pin 18 is 1500Ω. As a result, IF level refers to the actual signal that enters the SA608 input (Pin 18) which is about 21dB less than the “available power” at the generator. 2. By using 45kΩ load across the Quad detector coil, you will have Audio output at 115mV with –42dB distortion. November 3, 1992 4 Philips Semiconductors RF Communications Products Product specification Low voltage high performance mixer FM IF system CIRCUIT DESCRIPTION The SA608 is an IF signal processing system suitable for second IF systems with input frequency as high as 150MHz. The bandwidth of the IF amplifier and limiter is at least 2MHz with 90dB of gain. The gain/bandwidth distribution is optimized for 455kHz, 1.5kΩ source applications. The overall system is well-suited to battery operation as well as high performance and high quality products of all types. The input stage is a Gilbert cell mixer with oscillator. Typical mixer characteristics include a noise figure of 6.2dB, conversion gain of 17dB, and input third-order intercept of –9dBm. The oscillator will operate in excess of 200MHz in L/C tank configurations. Hartley or Colpitts circuits can be used up to 100MHz for xtal configurations. Butler oscillators are recommended for xtal configurations up to 150MHz. The output impedance of the mixer is a 1.5kΩ resistor permitting direct connection to a 455kHz ceramic filter. The input resistance of the limiting IF amplifiers is also 1.5kΩ. November 3, 1992 With most 455kHz ceramic filters and many crystal filters, no impedance matching network is necessary. The IF amplifier has 43dB of gain and 5.5MHz bandwidth. The IF limiter has 60dB of gain and 4.5MHz bandwidth. To achieve optimum linearity of the log signal strength indicator, there must be a 12dB(v) insertion loss between the first and second IF stages. If the IF filter or interstage network does not cause 12dB(v) insertion loss, a fixed or variable resistor or an L pad for simultaneous loss and impedance matching can be added between the first IF output (Pin 16) and the interstage network. The overall gain will then be 90dB with 2MHz bandwidth. 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. 5 SA608 The demodulated output of the quadrature drives an internal op amp. This op amp is configured as a unity gain buffer. A log signal strength completes the circuitry. The output range is greater than 90dB and is temperature compensated. This log signal strength indicator exceeds the criteria for AMPs or TACs cellular telephone. This signal is buffered through an internal unity gain op amp. The frequency check pin provides a buffered limiter output. This is useful for implementing an AFC (Automatic Frequency Check) function. This same output can also be used in conjunction with limiter output (Pin 11) for demodulating FSK (Frequency Shift Keying) data. Both pins are of the same amplitude, but 180° out of phase. NOTE: Limiter or Frequency Check output has drive capability of a 5kΩ minimum or higher in order to obtain 120mVRMS output level. NOTE: dB(v) = 20log VOUT/VIN Philips Semiconductors RF Communications Products Product specification Low voltage high performance mixer FM IF system –25dB, –10dB, 1500/50Ω PAD 50/50Ω PAD –29dB, 929/50Ω PAD 51.5 96.5 50.5 2430 3880 71.5 32.6 C20 C24 SW9 FLT1 SW8 19 C26 96.5 R18 3.3k 32.8 18 SW7 FLT2 17 16 –36dB, 156k/50Ω PAD 51.7 71.5 1.3k C16 C19 C21 C23 20 –10.6dB, 50/50Ω PAD R17 2.4k C22 SA608 15 SW6 SW5 C18 14 IF AMP C15 C17 13 12 11 LIMITER MIXER RSSI QUAD OSCILLATOR – + 1 2 3 4 – + VREG 5 6 7 8 9 10 R10 SW1 C1 SW3 R9 SW4 R11 C9 C8 SW11 L1 C2 C12 C7 R4 51.1 SW2 R1 C3 R3 R2 C5 C10 L2 DEEMPHASIS FILTER IFT1 R19 16k X1 C6 C4 EXT. LOC OSC 44.545 R7 30.5 45MHZ 45.06 MHZ R6 178 ”C” WEIGHTED AUDIO MEASUREMENT CIRCUIT R8 39.2 VCC AUDIO C14 FREQ CHECK MINI–CIRCUIT ZSC2–1B Automatic Test Circuit Component List C1 C2 C5 C6 C7 C8 C9 C10 C12 C14 C15 C17 C18 C21 C23 C25 100pF NPO Ceramic 390pF NPO Ceramic 100nF +10% Monolithic Ceramic 22pF NPO Ceramic 1nF Ceramic 10.0pF NPO Ceramic 100nF +10% Monolithic Ceramic 10µF Tantalum (minimum) * 2.2µF 100nF +10% Monolithic Ceramic 10pF NPO Ceramic 100nF +10% Monolithic Ceramic 100nF +10% Monolithic Ceramic 100nF +10% Monolithic Ceramic 100nF +10% Monolithic Ceramic 100nF +10% Monolithic Ceramic C26 C27 Flt 1 Flt 2 IFT 1 L1 L2 X1 R9 R10 R11 R14 R17 R18 R19 0.1µF +10% Monolithic Ceramic 2.2µF Ceramic Filter Murata SFG455A3 or equiv Ceramic Filter Murata SFG455A3 or equiv 455kHz (Ce = 180pF) Toko RMC–2A6597H 147–160nH Coilcraft UNI–10/142–04J08S 0.8µH nominal Toko 292CNS–T1038Z 44.545MHz Crystal ICM4712701 2kΩ +1% 1/4W Metal Film 10kΩ +1% 10kΩ +1% 5kΩ +1% 2.4kΩ +5% 1/4W Carbon Composition 3.3kΩ +5% 1/4W Carbon Composition 16kΩ +5% 1/4W Carbon Composition *NOTE: This value can be reduced when a battery is the power source. Figure 1. SA607 45MHz Test Circuit (Relays as shown) November 3, 1992 6 Philips Semiconductors RF Communications Products Product specification Low voltage high performance mixer FM IF system SA608 C26 R18 3.3k R17 2.4k FLT1 SW8 19 FLT2 C21 C23 20 C15 18 17 16 15 C18 14 C17 13 IF AMP 12 11 LIMITER MIXER RSSI QUAD OSCILLATOR – + – + 1 2 3 4 VREG 5 6 C1 7 8 9 10 C9 C8 C12 C2 L1 C7 C5 C10 L2 C6 IFT1 R19 11k X1 C14 RSSI OUTPUT VCC AUDIO OUT FREQ CHECK Product Board SA608D/DK Component List C1 C2 C5 C6 C7 C8 C9 C10 C12 C14 C15 C17 C18 C19 C21 C23 51pF NPO Ceramic 220pF NPO Ceramic 100nF +10% Monolithic Ceramic 5-30pF NPO Ceramic 1nF Ceramic 10.0pF NPO Ceramic 100nF +10% Monolithic Ceramic 10µF Tantalum (minimum) * 2.2µF 100nF +10% Monolithic Ceramic 10pF NPO Ceramic 100nF +10% Monolithic Ceramic 100nF +10% Monolithic Ceramic 390pF +10% Monolithic Ceramic 100nF +10% Monolithic Ceramic 100nF +10% Monolithic Ceramic C25 C26 C27 Flt 1 Flt 2 IFT 1 L1 L2 X1 R9 R10 R11 R14 R17 R18 R19 100nF +10% Monolithic Ceramic 0.1µF +10% Monolithic Ceramic 2.2µF Ceramic Filter Murata SFG455A3 or equiv Ceramic Filter Murata SFG455A3 or equiv 330µH TOKO 303LN–1130 0.33µH TOKO SCB–1320Z 1.2µH Coilcraft 1008CS–122 44.545MHz Crystal Hy-Q 2kΩ +1% 1/4W Metal Film 8.2kΩ +1% 10kΩ +1% 10kΩ +1% 2.4kΩ +5% 1/4W Carbon Composition 3.3kΩ +5% 1/4W Carbon Composition 16kΩ +5% 1/4W Carbon Composition *NOTE: This value can be reduced when a battery is the power source. Figure 2. SA608 45MHz Test Circuit (Relays as shown) November 3, 1992 7 C19 390pF Philips Semiconductors RF Communications Products Product specification Low voltage high performance mixer FM IF system RF GENERATOR 45MHz SA608 SA608 DEMO-BOARD RSSI AUDIO VCC (+3) DE-EMPHASIS FILTER DC VOLTMETER C–MESSAGE SCOPE HP339A DISTORTION ANALYZER Figure 3. SA608 Application Circuit Test Set Up NOTES: 1. C-message: The C-message and de-emphasis filter combination has a peak gain of 10 for accurate measurements. Without the gain, the measurements may be affected by the noise of the scope and HP339 analyzer. The de-emphasis filter has a fixed -6dB/Octave slope between 300Hz and 3kHz. 2. Ceramic filters: The ceramic filters can be 30kHz SFG455A3s made by Murata which have 30kHz IF bandwidth (they come in blue), or 16kHz CFU455Ds, also made by Murata (they come in black). All of our specifications and testing are done with the more wideband filter. 3. RF generator: Set your RF generator at 45.000MHz, use a 1kHz modulation frequency and a 6kHz deviation if you use 16kHz filters, or 8kHz if you use 30kHz filters. 4. Sensitivity: The measured typical sensitivity for 12dB SINAD should be 0.35µV or –116dBm at the RF input. 5. Layout: The layout is very critical in the performance of the receiver. We highly recommend our demo board layout. 6. 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 500mV or higher, it means the receiver is in regenerative mode. In that case, the receiver sensitivity will be worse than expected. 7. Supply bypass and shielding: All of the inductors, the quad tank, and their shield must be grounded. A 10-15µF or higher value tantalum capacitor on the supply line is essential. A low frequency ESR screening test on this capacitor will ensure consistent good sensitivity in production. A 0.1µF bypass capacitor on the supply pin, and grounded near the 44.545MHz oscillator improves sensitivity by 2-3dB. 8. R5 can be used to bias the oscillator transistor at a higher current for operation above 45MHz. Recommended value is 22kΩ, but should not be below 10kΩ. November 3, 1992 8 Philips Semiconductors RF Communications Products Product specification Low voltage high performance mixer FM IF system SA608 mA 6 VCC = 7V 5 VCC = 5V 4 VCC = 3V 3 VCC = 2.7V °C 2 –55 –35 –15 5 25 45 65 85 105 Figure 4. ICC vs Temperature –8.0 –8.5 50 Ω INPUT INTERCEPT POINT (dBm) –9.0 2.7V 3V –9.5 –10.0 7V –10.5 –11.0 –11.5 –12.0 –12.5 –13.0 –13.5 –14.0 –40 –30 –20 –10 0 10 20 30 40 50 60 Temperature (°C) Figure 5. Third Order Intercept Point vs Supply Voltage November 3, 1992 9 70 80 125 Philips Semiconductors RF Communications Products Product specification Low voltage high performance mixer FM IF system SA608 8.00 7.75 7.50 7.25 7.00 NOISE FIGURE 6.75 7.0V 6.50 6.25 3V 6.00 2.7V 5.75 5.50 5.25 5.00 –40 –30 –20 –10 0 10 20 30 40 50 60 70 80 70 80 TEMPERATURE (°C) Figure 6. Mixer Noise Figure vs Supply Voltage 18.00 17.75 2.7V CONVERSION GAIN (dB) 17.50 3V 17.25 7.0V 17.00 16.75 16.50 16.25 16.00 –40 –30 –20 –10 0 10 20 30 40 50 60 TEMPERATURE (°C) Figure 7. Conversion Gain vs Supply Voltage November 3, 1992 10 Philips Semiconductors RF Communications Products Product specification Low voltage high performance mixer FM IF system SA608 20 10 0 RF = 45MHz IF = 455kHz IF OUTPUT POWER (–dBm) –10 –20 –30 –40 3rd ORDER PRODUCT FUND PRODUCT –50 –60 –70 *50Ω INPUT –80 –66 –56 –46 –36 –26 –16 –6 4 14 24 RF* INPUT LEVEL (dBm) Figure 8. Mixer Third Order Intercept and Compression November 3, 1992 11 34 Philips Semiconductors RF Communications Products Product specification Low voltage high performance mixer FM IF system SA608 5 AUDIO 0 –5 DECIBELS (dB) –10 –15 VCC = 3V RF = 45MHz –20 DEVIATION = ±8kHz AUDIO LEVEL = 52.5mVRMS –25 –30 AM REJECTION –35 –40 THD + NOISE –45 –50 –55 –60 NOISE –65 –125 –115 –105 –95 –85 –75 –65 –55 –45 –35 –25 –35 –25 RF LEVEL (dBm) Figure 9. Sensitivity vs RF Level (–40°C) 5 AUDIO 0 –5 –10 DECIBELS (dB) VCC = 3V RF = 45MHz –20 DEVIATION = ±8kHz –25 AUDIO LEVEL = 58.5mVRMS –30 AM REJECTION –35 –40 –45 –50 THD + NOISE –55 –60 –65 –125 NOISE –115 –105 –95 –85 –75 –65 –55 RF LEVEL (dBm) Figure 10. Sensitivity vs RF Level (+25°C) November 3, 1992 12 –45 Philips Semiconductors RF Communications Products Product specification Low voltage high performance mixer FM IF system SA608 5 AUDIO 0 –5 DECIBELS (dB) –10 –15 VCC = 3V RF = 45MHz –20 DEVIATION = ±8kHz AUDIO LEVEL = 63.5mVRMS –25 –30 AM REJECTION –35 –40 –45 THD + NOISE –50 –55 –60 –65 –125 NOISE –115 –105 –95 –85 –75 –65 –55 –45 –35 –25 RF LEVEL (dBm) Figure 11. Sensitivity vs RF Level (Temperature 85°C) 5 AUDIO 0 –5 –10 VCC = 3V RF = 45MHz RF LEVEL = –45dBm –15 DECIBELS (dB) –20 DEVIATION = ±8kHz AUDIO LEVEL = +58.6mVRMS –25 –30 –35 –40 DISTORTION –45 –50 AM REJECTION –55 –60 NOISE –65 –55 –35 –15 5 25 45 TEMPERATURE (°C) 65 85 105 Figure 12. Relative Audio Level, Distortion, AM Rejection and Noise vs Temperature November 3, 1992 13 125 Philips Semiconductors RF Communications Products Product specification Low voltage high performance mixer FM IF system SA608 2.400 2.000 +85°C VOLTAGE (V) 1.600 ROOM 1.200 –40°C 0.800 0.400 0.000 –95 –85 –75 –65 –55 –45 –35 –25 –15 –5 5 IF LEVEL (dBm) Figure 13. RSSI (455kHz IF @ 3V) 2.1 2.0 1.9 1.8 1.7 1.6 VOLTAGE (V) 1.5 1.4 +85°C 1.3 +27°C 1.2 –40°C 1.1 1.0 0.9 0.8 0.7 0.6 0.5 0.4 0.3 –125 –115 –105 –95 –85 –75 –65 –55 RF LEVEL (dBm) Figure 14. RSSI vs RF Level and Temperature - VCC = 3V November 3, 1992 14 –45 –35 –25 Philips Semiconductors RF Communications Products Product specification Low voltage high performance mixer FM IF system SA608 V 300 VCC = 7V 250 mV RMS 200 VCC = 5V 150 VCC = 3V 100 VCC = 2.7V 50 °C 0 –55 –35 –15 5 25 45 65 Figure 15. Audio Output vs Temperature November 3, 1992 15 85 105 125