Si4740/41/42/43/44/45 Automotive AM/FM Radio Receiver Description Features The Si474x receiver family applies 100% RF CMOS technology to bring digital low-IF radio technology to the automotive receiver market. The Si474x receiver family builds on Silicon Laboratories’ highly successful broadcast audio radio products, offering design simplicity, unmatched integration, programmability, and automotive quality and reliability. The Si474x receiver family supports world-wide FM bands from 64–108 MHz and AM bands from 520–1710 kHz. The Si474x supports AM/FM, weather band, shortwave, and longwave radio bands. All odd-numbered part numbers in the family support international RDS/RBDS protocols. The Si474x family leverages Silicon Laboratories’ patented digital architecture, delivering superior RF performance and interference rejection. The proven digital radio technology provides excellent sensitivity in weak signal environments, and superb selectivity and inter-modulation immunity in strong signal environments. The solution offers programmable AM/FM channel spacing and filters, auto-calibrated digital tuning, and proven AM/FM seek functionality based on multiple signal quality and band parameters. The family offers highly flexible and advanced audio features such as noise blanking, programmable soft mute, and multi-path detection and mitigation. The Si474x receiver system has a minimal bill of materials requiring a small amount of board space. The high level of integration provides a complete, tested broadcast audio receiver that is ideal for primary automotive radio receivers. - Worldwide FM band support (64–108 MHz) Worldwide AM band support (520–1710 kHz) Shortwave, longwave support (Si4742/43/44/45 only) Weather band support (Si4742/43 only) Received signal quality indicators (RSSI, SNR, adjacent channel, wideband AM) Multipath detection/mitigation AM and FM noise blankers (Si4742/43/44/45 only) AM and FM programmable seek tuning AM and FM programmable soft mute control AM and FM adjustable channel bandwidth filters FM stereo-mono blending FM Hi-Cut control (Si4742/43/44/45 only) Digital FM stereo decoder RDS/RBDS processor (Si4741/43/45 only) Automatic frequency control (AFC) Automatic gain control (AGC) Image rejection mixer Frequency synthesizer with integrated VCO Low-IF direct conversion with no ceramic filters Analog or digital (I2S) outputs 3.0 to 3.6 V supply voltage Programmable reference clock AECQ-100 certified • –40 to 85 ºC operation - 24-pin 4 x 4 mm QFN package • Pb-free/RoHS compliant Applications - OEM automotive radio systems - After-market automotive radio systems - Automotive radio modules Si474x FMI RDS LNA WEAK SIGNAL CONDITION AGC ADC AMI LNA GND AGC DOUT DIGITAL AUDIO DFS DCLK DAC ROUT DAC LOUT DSP ADC AGC VDD AFC AM/FM Receiver QUALITY DETECTOR CNTRL GPO1-3 VIO RST RCLK GND LDO SEN SCLK SDIO 3.0–3.6 V Copyright © 2008 by Silicon Laboratories 10.23.08 Si4740/41/42/43/44/45 Automotive AM/FM Radio Receiver Selected Electrical Specifications1 (VDD = 2.7 to 5.5 V, VIO = 1.5 to 3.6 V, TA = –40 to 85 °C) Parameter Test Condition Min Typ Max Unit 64 — — — 2 8 108 — — MHz µV EMF µV EMF — 63 — dB — 0.1 — % — — — — 105 80 50 70 — — — — dBµV EMF mVrms dB dB — 55 — dB — 45 — dB FM Input Frequency Sensitivity RDS Sensitivity Audio S/N (Mono)2,3 Audio THD (Mono)2,3 Input IP3 Audio Output Voltage Adjacent Channel Selectivity Alternate Channel Selectivity AM Suppression4 Audio Stereo Separation4 (S+N)/N = 26 dB f = 2 kHz, RDS BLER < 5% fMOD = 1 kHz, f = 22.5 kHz, VEMF = 60 dBµVEMF fMOD = 1 kHz, f = 75 kHz, VEMF = 60 dBµVEMF f1 = 4000 kHz; f2 = 8000 kHz ±200 kHz ±400 kHz m = 0.3; f = 22.5 kHz; fRF = 76 to 108 MHz; Measured at VEMF = 60 dBµVEMF fRF = 76 to 108 MHz; Measured at VEMF = 60 dBµVEMF; f = 75 kHz Voltage5 3 — 3.6 V Supply Current5 — 26 — mA 520 — — 28 1710 — kHz µV EMF — 53 — dB — 0.3 — % — 112 — dBµV 54 — — 60 40 60 66 — — mVrms dB dB Supply AM Input Frequency Sensitivity (S+N)/N = 26 dB 30% modulation, fMOD =1 kHz, RF level = 74 dBµV EMF; f = 22.5 kHz 30% modulation, fMOD =1 kHz, RF level = 74 dBµV EMF; f = 22.5 kHz f1 = 40 kHz; f2 = 80 kHz Audio S/N4,6 Audio THD4,6 Input IP3 7 Audio Output Voltage4 Adjacent Channel Selectivity Alternate Channel Selectivity ±10 kHz ±20 kHz Notes: 1. 2. 3. 4. 5. 6. 7. Specifications refer to Si474x application circuit input. BAF = 300 Hz to 15 kHz. fRF = 76 to 108 MHz. FMOD = 1 kHz, 75 µs de-emphasis, MONO = enabled, and L = R unless noted otherwise. Applies to both FM and AM modes. AGC is disabled. Specification refers to Si474x input. NC NC NC GPO1/AGC2 GPO2/INT GPO3/DCLK Pin Assignments 24 23 22 21 20 19 FMI 1 4 x 4 x 0.85 mm 24-pin QFN Package Information Symbol A A1 b D D2 e E E2 L aaa bbb ccc ddd eee 18 DFS RFGND 2 17 DOUT AGC1 3 16 LOUT GND PAD NC 4 15 ROUT GND 5 14 GND 9 10 11 12 SDIO RCLK VIO RST 8 SCLK 13 VDD 7 SEN AMI 6 AM/FM Receiver Millimeters Min Nom Max 0.80 0.85 0.90 0.00 0.02 0.05 0.18 0.25 0.30 4.00 BSC 2.00 2.10 2.20 0.50 BSC 4.00 BSC 2.00 2.10 2.20 0.30 0.40 0.50 — — 0.10 — — 0.10 — — 0.08 — — 0.10 — — 0.10 Copyright © 2008 by Silicon Laboratories Silicon Laboratories and Silicon Labs are trademarks of Silicon Laboratories Inc. Other products or brandnames mentioned herein are trademarks or registered trademarks of their respective holders. 10.23.08