SC1088. Silan Semiconductors FM RECEIVER CIRCUIT FOR BATTERY SUPPLY HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD

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1 Semiconductors FM RECEIVER CIRCUIT FOR BATTERY SUPPLY DESCRIPTION The is a bipolar integrated circuit for use in mono portable and pocket radios. It is used when a minimum of perpheral components (of small dimensions and low costs) is important. The circuit contains a frequency-locked-loop(fll) system with an intermediate frequency(if) of about 70kHz. Selectivity is achieved by active RC-filters. De-tuning related to the IF and too weak input signal is suppressed by the mute circuit. FEATURES * Equipped with all stages of a mono receiver from antenna to audio output. * Mute Circuit * Search tuning with a single varicap diode * Mechanical tuning with integrating C * AM application supported * Power supply polarity protection * Power supply voltage down to.8v SOP-6 APPLICATION. Mechanical tuning: This is possible with or without integrated C circuit. Electrical tuning: This is realized by one directional(band-up) search tuning facility, including RESET to the lower-band limit. PIN CONFIGURATIONS 6 TUNE VO 5 LOOP 3 4 OSC CLIM IF FB 6 CLP 7 0 CLP VOIF 8 9

2 Semiconductors BLOCK DIAGRAM 80pF 3.9nF 3.3nF 330pF pF 5 V Mixer VCO.kΩ.kΩ + V 6kΩ IF Limter 4 4 V 6 Searching tuning & R S V kΩ All pass Filter Demodulator 6kΩ Loop Filter - V 0kΩ 5kΩ V0 68pF 0pF 70nH 78nH 680pF 0nF 5.6kΩ 68nF RESET Note: V,V and V3 are internal voltages. Fig. Block Dirgram and Application Circuit for Search Tuning. RUN nf Vo kω.8nf

3 Semiconductors ABSOLUTE MAXIMUM RATINGS Characteristic Symbol Value Unit Supply Voltage Vp 5 V Operating Temperature Tamb -0 ~ +70 C Storage Temperature Tstg -55 ~ +50 C DC ELECTRICAL CHARACTERISTICS (Tamb=5 C,Vp=3V,Unless otherwise specified) Parameter Symbol Test conditions Min Typ Max Unit Supply Voltage(pin 4) Vp V Supply Current(Pin 4) Ip ma DC voltage of pin V V DC voltage of pin 3 V V DC voltage of pin 6 and 7 V6, V DC voltage of pin 8 V V DC voltage of pin 9,0 and 3 V9,0, V DC voltage of pin and V, V DC voltage of pin 5 V V output current on pin I µa Oscillator current on pin 5 I µa AC ELECTRICAL CHARACTERISTICS Tamb=5 C,Vp=3V,Firf=96MHz modulated with f=±.5khz and fm=khz deviation;emf=0.3mv(e.m.f. at a sourse impedance of 75Ω),and measurement taken in fig.3 Unless otherwise specified Parameter Symbol Test conditions Min Typ Max Unit Vo=-3dB;Vo=0dB at RF Sensitivityinput voltage Vi(rms) Vi=mV;see Fig. Mute OFF 3 6 µv Mute ON 3 6 µv (S+N)/N=6dB 5 0 µv Signal handling THD<0%, f=±75khz 00 mv Signal-to -noise ratio (S+N)/N See fig. 56 db Total Harmonic distortion THD f=±.5khz.4 % f=±75khz % AM suppression of output voltage AMS FM: khz; ±75kHz AM: khz; MOD=80% 47 5 db Ripple rejection RR Vp=00mVrms,f=kHz 7 0 db Audio output signal Vo(rms) RL=kΩ mv Search Tuning(with V0 and C6=) See Fig. Minimum output voltage on pin 6 V6 Limiting point Vp-.85 Tuning steepness V/ t Voltage at pin mv/sec Oscillator steepness fosc/ t MHz/sec C steepness IC/ V3 Voltage at pin µs V 3

4 Semiconductors PIN DESCRIPTIONS Pin No. Symbol Description Pin No. Symbol Description Mute output 9 ViIF IF input to limiter amplifier VO Audio frequency output Low-pass capacitor of IF 0 CLP signal limiter amplifier 3 LOOP loop filter Radio frequency input 4 Vp Supply voltage Radio frequency input 5 OSC Oscillator resonat circuit 3 CLIM Limiter offset voltage capacitor 6 IF FB IF feedback 4 Ground 7 CLP Low-pass capacitor of db All-pass filter capacitor.input 5 amplifier for search tuning 8 VOIF IF output to external coupling capacitor(high-pass) 6 TUNE Electrical tuning/c output 0 VO (db) S+N Noise : Mute ON : Mute OFF EMF (V) Fig. Input sensitivity 4

5 Semiconductors TEST AND APPLICATION CIRCUIT Rs=75Ω 0pF 0kΩ ViRF EMF 70nH TUNE VO LOOP 68pF CLIM OSC IF FB pF CLP CLP 330pF VOIF 3,9nF Disable.8nF kω nf.kω 78nH 3.3nF 80pF 8pF VO 0nF 7pF C Fig. 3 Test circuit and application for mechanical tuning 0pF 0kΩ ViRF TUNE VO LOOP 70nH 68pF CLIM OSC IF FB pF CLP CLP 330pF VOIF 3.9nF.8nF kω nf.kω 8pF 78nH 3.3nF 80pF VO 0nF 7pF C 68nF C D V0 Fig. 4 Application circuit with C for mechanical tuning 5

6 Semiconductors Oscillator resonat circuit FM 33pF AM FM AM pf 4.7nF 4.7nF 80pF nf 47nF 0kΩ 33pF 33pF µf µf 0nF 7kΩ Ω 5.Ω kω 4.7nF.7kΩ BAW6 0nF 00kΩ µf 330pF AM antenna earphone Volume Low High 3.9nF Transformer UTC764 AM IF VOIF CLP IF FB OSC LOOP VO CLP CLIM TUNE Fig.5 AM application circuit OFF Battery switch ON Amplifier 6

7 Semiconductors PACKAGE OUTLINE SOP UNIT:mm