Ordering number : EN5688 Monolithic Linear IC LA1837 Single-Chip Home Stereo IC with Electronic Tuning Support Overview Package Dimensions The LA1837 is a single-chip AM/FM IF and MPX IC that supports electronic tuning and was developed for use in home stereo systems. It is optimal for use in automatic station selection systems that use the SD and IF counting techniques. unit: mm 3061-DIP30S [LA1837] Functions AM: RF amplifier, mixer, oscillator, IF amplifier, detector AGC, oscillator buffer, S-meter, narrowband SD, IF buffer FM IF: IF amplifier, quadrature detector, S-meter, Scurve detector, IF buffer output MPX: PLL stereo decoder, stereo display, forced mono, VCO stop, post amplifier, audio muting, adjacent channel interference rejection function Features SANYO: DIP30S • On-chip MPX VCO (no external components required) • Adjacent channel interference rejection function (third and fifth order) • Supports both the SD and the IF counting techniques. • The AM and FM SD sensitivities can be set independently. • The AM and FM output levels can be set independently. • Improved AM practical sensitivity and high-input distortion characteristics Specifications Maximum Ratings at Ta = 25°C Parameter Symbol Maximum supply voltage VCC max Allowable power dissipation Pd max Conditions Ta ≤ 70°C Ratings Unit 12 V 550 mW Operating temperature Topr –20 to + 70 °C Storage temperature Tstg –40 to +125 °C Ratings Unit Operating Conditions at Ta = 25°C Parameter Recommended supply voltage Operating voltage range Symbol Conditions VCC VCC op 9 V 7 to 11 V SANYO Electric Co.,Ltd. Semiconductor Bussiness Headquarters TOKYO OFFICE Tokyo Bldg., 1-10, 1 Chome, Ueno, Taito-ku, TOKYO, 110 JAPAN 82097HA(OT) No. 5688-1/9 LA1837 Electrical Characteristics at Ta = 25°C, VCC = 9 V, in the specified Test Circuit Parameter Symbol Conditions Ratings min typ Unit max [FM Mono Characteristics] fc = 10.7 MHz, fm = 1 kHz, with the coil adjusted so that VAFC – VREG = 0 V Current drain ICCO-FM Demodulation output VOFM With no input 18 31 44 100 dBµ, 100% mod. The pin 16 output 730 1100 1460 mVrms mA –1.5 dB Channel balance C.B-mono 100 dBµ, 100% mod. The pin 16 output/pin 17 output 0 +1.5 Total harmonic distortion (mono) THDFM(1) 100 dBµ, 100% mod. The pin 16 output 0.3 1.3 % Total harmonic distortion (mono) THDFM(2) 100 dBµ, 200% mod. The pin 16 output 1.0 5 % S/NFM 100 dBµ, 100% mod. The pin 16 output 72 80 dB 100 dBµ, AM 30 % mod. The pin 16 output 45 65 dB 100 dBµ, 100% mod. Referenced to the output. The input such that the output is down –3 dB. 26 32 Signal-to-noise ratio AM rejection ratio AMR Limiting input voltage –3 dBL.S. LED sensitivity SDOn-FM LED bandwidth SDBW IF count buffer output S-meter output Muting attenuation 38 dBµ dBµ 51 60 69 100 dBµ 85 120 170 kHz VIFBuff-FM 100 dBµ. The pin 13 output 80 120 160 mVrms V VSM-FM(1) 0 dBµ. The pin 11 output 0 0.1 0.5 VSM-FM(2) 100 dBµ. The pin 11 output 3.6 4.3 5.0 Mute-Att 100 dBµ, 100% mod. The pin 16 output 75 85 dB dB V [FM Stereo Characteristics] fc = 10.7 MHz, 100 dBµ, fm = 1 kHz, L + R = 90%, Pilot = 10% Separation (left) SepL L mod. The pin 16 output/pin 17 output 30 45 Separation (right) SepR R mod. The pin 17 output/pin 16 output 30 45 Stereo on level STON The pilot modulation such that V7 is under 0.7 V. 1.3 2.7 Stereo off level STOFF The pilot modulation such that V7 is over 4.5 V. 1.5 L+R mod. The pin 16 output 0.3 Brej-3rd fs = 113 kHz, Vs = 90 %, Pilot = 10 %, The pin 16 output vs. the L-R mod. 1 kHz demodulated output 40 dB Brej-5th fs = 189 kHz, Vs = 90 %, Pilot = 10 %, The pin 16 output vs. the L-R mod. 1 kHz demodulated output 40 dB Total harmonic distortion (main) THD-main Adjacent channel interference rejection ratio dB 5 % 1.3 % % [AM Characteristics] fc = 1000 kHz, fm = 1 kHz Current drain Detector output Signal-to-noise ratio Total harmonic distortion (mono) LED sensitivity ICCO-AM With no input 15 25 35 mA VOAM(1) 23 dBµ, 30% mod. The pin 16 output 100 180 360 mVrms 500 mVrms VOAM(2) 80 dBµ, 30% mod. The pin 16 output 200 320 S/NAM(1) 23 dBµ, 30% mod. The pin 16 output 18 22 S/NAM(2) 80 dBµ, 30% mod. The pin 16 output 49 55 THDAM(1) 80 dBµ, 30% mod. The pin 16 output 0.4 1.2 THDAM(2) 80 dBµ, 80% mod. The pin 16 output 1.0 4.0 % 17 27 37 dBµ SDOn-AM dB dB % Local oscillator buffer output VOSC-AM With no input. The pin 30 output 110 160 220 mVrms IF counter buffer output VIFBuff-AM 80 dBµ, no modulation. The pin 13 output 160 220 300 mVrms ST-IF output VSTIF-AM 80 dBµ, no modulation. The pin 7 output 16 34 48 mVrms S-meter output VSM-AM 0 dBµ, no modulation. 0 0 0.2 V Allowable power dissipation, Pd max – mW Pd max – Ta Ambient temperature, Ta – °C No. 5688-2/9 LA1837 FM SD ADJ Block Diagram 3 rd 5 th FM DECODER ANTI-BIRDIE Test Circuit Diagram No. 5688-3/9 LA1837 Coil Specifications · IFT YD-1073-1 (Mitsumi Electric Co., Ltd.) · AM oscillator (for the DUT) HW-50425 (Mitsumi Electric Co., Ltd.) ➀-➁ 58T ➂-➁ 2T ➃-➅ 7T ➃-➅ 9T ➁-➂ 94T ➁-➀ 86T fO = 450 kHz QO ≥ 80 QO = 110 L = 270 µH Includes an internal 180-pF capacitor. · FM detector 600BEAS-9715Z (The Toko Electric Corporation) ➂-➀ SFU450B included. 22T f = 10.7 MHz QO = 40 Includes an internal 82-pF capacitor. Pin Functions Pin No. Pin function Pin voltage (V) Pin description 1 FM IF input Vreg Input impedance ri = 330 Ω 2 AM mixer output VCC Connect the mixer coil between this pin and VCC. 3 FM IF input bypass Vreg Also functions as the MPX regulator filter. 4 AM IF input Vreg Input impedance ri = 2 kΩ 5 GND 0V 6 7 TU - LED ST - LED AM-IF output VCC VCC 8 VCC VCC 9 FM detector VCC Equivalent circuit See pin 1. Active low Open collector output AM stereo IF output (pin 7) The current input must not exceed 150 µA. Recommended detector coil: 600BEAS9715Z (The Toko Electric Corporation) Continued on next page. No. 5688-4/9 LA1837 Continued from preceding page. Pin No. Pin Function Pin voltage (V) Pin description Equivalent circuit Recommended narrow band CF: BFU450 C4N (Murata Mfg. Co., Ltd.) 10 AM narrow band CF connection 1.3 V 11 FM S-meter output 0V AM S-meter output 12 AM SD sensitivity adjustment 0 V (AM) If the narrow band SD is not used, bypass this circuit with a 50-Ω resistor and a 0.047µF capacitor connected in series. RL = 8 kΩ The AM SD sensitivity is adjusted with the value of the external resistor connected between this pin and ground. V13 ≤ 0.5 V: Reception state 13 AM and FM IF buffer output, output control switch (mute switch) Phase comparator 14 low-pass filter (FM/AM switching) 0V 1.4 V ≤ V13 ≤ 2.2 V: IF buffer output turned on V13 ≥ 3.5 V: IF buffer output and muting are turned on Connecting this pin to ground through a resistor sets the IC to AM mode. VCC – 1.4 (FM) Resistor value limits: 2.7 kΩ (when VCC = 7 V) 0 V (AM) 3.9 kΩ (8 V) 5.1 kΩ (9 V) 6.2 kΩ (10 V) 7.5 kΩ (11 V) If a current of 50 µA or greater flows from this pin, the system is forced to mono. Pilot detector low-pass 15 filter (forced mono) VCC – 1.0 (VCO stop) The resistor limit values are the same as for pin 14. Output impedance ro = 200 Ω 16 17 18 Post amplifier input and output Vreg Vreg 21 Pin 16: right output, pin 17: left output Inverting inputs Pin 18: right input, pin 19: left input 19 20 Connecting this pin to ground stops the VCO. RNF = 33 kΩ MPX output 3.5 V 3.5 V Output impedance ro = 3.3 kΩ Pin 20: right de-emphasis Pin 21: left de-emphasis Continued on next page. No. 5688-5/9 LA1837 Continued from preceding page. Pin No. 22 Pin Function MPX input Pin voltage (V) 2.9 V Pin description Equivalent circuit Input impedance ri = 20 kΩ Output impedance ro = 3.0 kΩ 23 FM demodulator output 2.8 V (FM) 2.8 V (AM) The separation can be modified by inserting a capacitor between this pin and ground. Set VO sub/VO main to be about 0 dB. Output impedance ro = 3.3 kΩ 0 V (FM) The AM frequency characteristics can be modified by adjusting the time constants of the circuits between this pin and pin 22, and between this pin and ground. 24 AM detector output 25 AM AGC 26 AFC Vreg The FM SD bandwidth can be modified with the external resistor connected between this pin and pin 28. 27 AM RF input Vreg Use this pin at the same potential as pin 28. 28 REG Vreg Vreg = 3.6 V 29 OSC Vreg Use an oscillator coil between this pin and pin 28. 30 Oscillator buffer output, FM SD sensitivity adjustment 1.6 V (FM) The FM SD sensitivity can be modified with the external resistor connected between this pin and ground. 0.5 V (AM) 0 V (FM) 0.5 V (AM) 1.3 V (AM) The built-in load resistor R = 11 kΩ. Output impedance ro = 20 Ω No. 5688-6/9 LA1837 FM THD/V THD/VSM Characteristics SM Characteristics Output – dBm Total harmonic distortion, THD – % S-meter output, VSM – V Overall FM Characteristics FM THD Band Characteristics Distortion vs. Frequency Characteristics Total harmonic distortion, THD – % Iinput – dBµ Total harmonic distortion, THD – % Input – dBµ Frequency, fC – MHz Frequency, freq – kHz Separation vs. Frequency Characteristics Adjacent Channel Interference Rejection Ratio Vobat – dB Separation – dB Referenced to the L-R demodulated output. Frequency, fS – Hz Capture Range Characteristics SD Sensitivity Adjustment Characteristics SD on – dBµ Capture range – % Frequency, freq – kHz Pilot – mV Rsdadj – kΩ No. 5688-7/9 LA1837 SD Sensitivity Adjustment Characteristics Overall AM Characteristics Output – dBm Input – dBµ AM THD/VSM Characteristics AM Detector Output Frequency Characteristics (1) S-meter output, VSM – V Output voltage, VO –dBV Radj – kΩ Frequency, fm – kHz AM Detector Output Frequency Characteristics (2) Distortion vs. Ambient Temperature Characteristics Total harmonic distortion, THD – % Input – dBµ Output voltage, VO –dBV Total harmonic distortion, THD – % SD BW – kHz Output Frequency, fm – kHz Ambient temperature, Ta – °C S/N – dB Separation, Sep – dB Separation vs. Ambient Temperature Characteristics Ambient temperature, Ta – °C No. 5688-8/9 LA1837 ■ No products described or contained herein are intended for use in surgical implants, life-support systems, aerospace equipment, nuclear power control systems, vehicles, disaster/crime-prevention equipment and the like, the failure of which may directly or indirectly cause injury, death or property loss. ■ Anyone purchasing any products described or contained herein for an above-mentioned use shall: ➀ Accept full responsibility and indemnify and defend SANYO ELECTRIC CO., LTD., its affiliates, subsidiaries and distributors and all their officers and employees, jointly and severally, against any and all claims and litigation and all damages, cost and expenses associated with such use: ➁ Not impose any responsibility for any fault or negligence which may be cited in any such claim or litigation on SANYO ELECTRIC CO., LTD., its affiliates, subsidiaries and distributors or any of their officers and employees jointly or severally. ■ Information (including circuit diagrams and circuit parameters) herein is for example only; it is not guaranteed for volume production. SANYO believes information herein is accurate and reliable, but no guarantees are made or implied regarding its use or any infringements of intellectual property rights or other rights of third parties. This catalog provides information as of August, 1997. Specifications and information herein are subject to change without notice. No. 5688-9/9