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any and all sanyo products described or contained herein do not have specifications that can handle applications that require extremely high levels of reliability, such as life-support systems, aircrafts control systems, or other applications whose failure can be reasonably expected to result in serious physical and/or material damage. consult with your sanyo representative nearest you before using any sanyo products described or contained herein in such applications. sanyo assumes no responsibility for equipment failures that result from using products at values that exceed, even momentarily, rated values (such as maximum ratings, operating condition ranges, or other parameters) listed in products specifications of any and all sanyo products described or contained herein. overview the la1787m integrates all six blocks required in a car radio tuner on a single chip. functions ? fm front end ? fm if ? noise canceller ? multiplex ? am up-conversion ? fm/am switch ? mrc features ? improved noise reduction methods the fm front end provides excellent 3-signal characteristics equivalent to those of the la1193m. superlative listenability due to improved medium and weak field noise canceller characteristics. improved separation characteristics anti-birdie filter improved am and fm thermal characteristics excellent fm signal meter linearity modified n.c. circuit for improved noise rejection ? improved am adjacent channel interference characteristics ( ? 40 khz) ? double conversion am tuner (up conversion) reduces the number of external components required as compared to earlier double conversion tuners, in particular, no crystal is required (when used in conjunction with the lc72144). ? sample-to-sample variation reduction circuit built into the fm if circuit. (fixed resistors are used for the sd, keyed agc, mute on adjustment, att, snc, and hcc functions.) ? improved fm separation temperature characteristics ? the la1787 inherits the block arrangement of the la1780m and supports pin-compatible designs. package dimensions unit:mm 3159a-qip64e (14 14) monolithic linear ic ordering number : enn6655 72602rm (ot) no. 6655-1/54 sanyo electric co.,ltd. semiconductor company tokyo office tokyo bldg., 1-10, 1 chome, ueno, taito-ku, tokyo, 110-8534 japan single-chip tuner ic for car radios la1787m 14.0 17.2 14.0 17.2 0.15 0.35 0.8 (2.7) 3.0max 0.1 0.8 (1.0) 116 17 32 33 48 49 64 allowable power dissipation, pdmax mw ambient temperature, ta c mounted on a 40 80 1.3 mm 3 glass epoxy printed circuit board independent ic sanyo: qip64e (14 14) [la1787m]
ratings parameter symbol conditions min typ max unit [fm characteristics] at the fm if input current drain i cco -fm no input, i 40 + i 45 + i 54 + i 59 + i 60 + i 61 60 94 110 ma demodulation output v o -fm 10.7 mhz, 100db , 1 khz, 100%mod, the pin 15 output 205 310 415 mvrms pin 31 demodulation output v o -fm31 10.7 mhz, 100db , 1 khz, 100%mod, the pin 31 output 190 295 380 mvrms channel balance cb the ratio between pins 15 and 16 at 10.7 mhz, 100 db , 1 khz C1 0 +1 db total harmonic distortion thd-fm mono 10.7 mhz, 100 db , 1 khz, 100% mod, pin 15 0.3 1 % signal-to-noise ratio: if s/n-fm if 10.7 mhz, 100 db , 1 khz, 100% mod, pin 15 75 82 db am suppression ratio: if amr if 10.7 mhz, 100 db , 1 khz, f m = 1 khz, 30% am, pin 15 55 68 db att-1 10.7 mhz, 100 db , 1 khz. the pin 15 5 10 15 db attenuation when v33 goes from 0 to 2 v muting attenuation att-2 10.7 mhz, 100 db , 1 khz. the pin 15 15 20 25 db attenuation when v33 goes from 0 to 2 v * 1 att-3 10.7 mhz, 100 db , 1 khz. the pin 15 28 33 38 db attenuation when v33 goes from 0 to 2 v * 2 separation separation 10.7 mhz, 100 db , l+r = 90%, pilot = 10%. the pin 15 output 30 40 db ratio stereo on level st-on the pilot modulation such that v26 < 0.5 v 1.2 2.4 4.4 % stereo off level st-off the pilot modulation such that v26 > 3.5 v 0.6 1.6 % main total harmonic distortion thd-main l 10.7 mhz, 100 db , l+r = 90%, pilot = 10%. the pin 15 signal 0.3 1.2 % pilot cancellation pcan 10.7 mhz, 100 db , pilot = 10%. 20 30 db the pin 15 signal/the pilot level leakage. din audio snc output attenuation attsnc 10.7 mhz, 100 db , l-r = 90%, pilot = 10%. 1 5 9 db v28 = 3 v ? 0.6 v, pin 15 atthcc-1 10.7 mhz, 100 db , 10 khz, l+r = 90%, pilot = 10%. 0.5 4.5 8.5 db hcc output attenuation v29 = 3 v ? 0.6 v, pin 15 atthcc-2 10.7 mhz, 100 db , 10 khz, l+r = 90%, 6 10 14 db pilot = 10%. v29 = 3 v ? 0.1 v, pin 15 input limiting voltage vi-lim 100 db , 10.7 mhz, 30% modulation. the if input such 33 40 47 db that the input reference output goes down by 3 db muting sensitivity vi-mute the if input level (unmodulated) when v33 = 2 v 27 35 43 db sd-sen1 fm the if input level (unmodulated) (over 100 mv rms) 54 62 70 db sd sensitivity such that the if counter buffer output goes on sd-sen2 fm 54 62 70 db if counter buffer output v ifbuff-fm 10.7 mhz, 100 db , unmodulated. the pin 23 output 130 200 270 mvrms v sm fm-1 no input. the pin 24 dc output, unmodulated 0.0 0.1 0.3 v signal meter output v sm fm-2 50 db . the pin 24 dc output, unmodulated 0.4 1.0 1.5 v v sm fm-3 70 db . the pin 24 dc output, unmodulated 2.0 2.7 3.5 v v sm fm-4 100 db . the pin 24 dc output, unmodulated 4.7 5.5 6.2 v muting bandwidth bw-mute 100 db . the bandwidth when v33 = 2 v, unmodulated 150 220 290 khz mute drive output v mute-100 100 db , 0 db . the pin 33 dc output, unmodulated 0.00 0.03 0.20 v operating characteristics at ta = 25 c, v cc = 8.0v, in the specified test cricuit for the fm if input continued on next page. no. 6655- 2 /54 la1787m specifications maximum ratings at ta = 25 c operating conditions at ta = 25 c parameter symbol conditions ratings unit maximum supply voltage v cc 1 max pins 6, 40, and 61 9 v v cc 2 max pins 7, 45, 54, 59, and 60 12 v allowable power dissipation pd max ta 55 c 950 mw operating temperature topr C40 to +85 c storage temperature tstg C40 to +150 c parameter symbol conditions ratings unit recommended supply voltage v cc pins 6, 7, 40, 45, 54, 59, 60, and 61 8 v v cc st ind pin 26 5 v operating supply voltage range v cc op 7.5 to 9.0 v
ratings parameter symbol conditions min typ max unit [fm fe mixer input n-agc on input v n -agc 83 mhz, unmodulated. 81 88 95 db the input such that the pin 2 voltage is 2.0 v or below w-agc on input v w agc 83 mhz, unmodulated. the input such that the pin 2 104 110 116 db voltage is 2.0 v or below. (when the keyed agc is set to 4.0 v.) conversion gain a.v 83 mhz, 80 db , unmodulated. the fe cf output 19 30 48 mvrms oscillator buffer output v oscbufffm no input 85 110 165 mvrms [nc block] nc input (pin 30) gate time t gate1 f = 1 khz, for a 1- s, 100-mv p-o pulse 55 s noise sensitivity sn the level of a 1 = khz, 1- s pulse input that starts 40 mvp-o noise canceller operation. measured at pin 30. the pulse rejection effect provided by the noise canceller. nc effect sn-nc for a repeated 1- s wide pulse, frequency = 10 khz, 5 150 mv p-o. the ratio of the fm mode pin 15 output referenced to the am mode pin 15 output (effective value) [multipath rejection circuit] mrc input (pin 27) mrc output vmrc v24 = 5 v 2.2 2.3 2.4 v mrc operating level mrc-on the pin 32 input level at f = 70 khz such that 10 15 20 mvrms pin 24 goes to 5 v and pin 27 goes to 2 v [am characteristics] am ant input practical sensitivity s/n-30 1 mhz, 30 db , f m = 1 khz, 30% modulation, pin 15 20 db detector output v o -am 1 mhz, 74 db , f m = 1 khz, 30% modulation, pin 15 130 195 270 mvrms pin 31 detector output v o -am31 1 mhz, 74 db , f m = 1 khz, 30% modulation, pin 31 110 175 230 mvms agc f.o.m. v agc-fom 1 mhz, 74 db , referenced to the output, the input amplitude 51 56 61 db such that the output falls by 10 db. pin 15 signal-to-noise ratio s/n-am 1 mhz, 74 db , f m = 1 khz, 30% modulation 47 52 db total harmonic distortion thd-am 1 mhz, 74 db , f m = 1 khz, 80% modulation 0.3 1 % signal meter output v sm am-1 no input 0.0 0.2 0.5 v v sm am-2 1 mhz, 130 db , unmodulated 4.8 6 7.3 v oscillator buffer output v oscbuff am1 no input, the pin 15 output 185 230 mvrms wide band agc sensitivity w-agcsen1 1.4 mhz, the input when v46 = 0.7 v 92 98 104 db w-agcsen2 1.4 mhz, the input when v46 = 0.7 v (seek mode) 83 89 95 db sd sensitivity sd-sen1 am 1 mhz, the ant input level such that the if counter output turns on. 24 30 36 db sd-sen2 am 1 mhz, the ant input level such that the sd pin goes to the on state. 24 30 36 db if buffer output v ifbuff-am 1 mhz, 74 db , unmodulated. the pin 23 output 200 290 mvrms no. 6655- 3 /54 la1787m note: these measurements must be made using the either the ic-51-0644-824 or ks8277 ic socket (manufactured by yamaichi electro nics). * 1. when the resistor between pin 58 and ground is 200 k . * 2. when the resistor between pin 58 and ground is 30 k . continued from preceding page.
function list fm front end (equivalent to the sanyo la1193) ? double input type double balanced mixer ? pin diode drive agc output ? mosfet second gate drive agc output ? keyed agc adjustment pin ? differential if amplifier ? wide band agc sensitivity setting pin, and narrow band agc sensitivity setting pin ? local oscillator fm if ? if limiter amplifier ? s-meter output (also used for am) 6-stage pickup ? multipath detection pin (shared fm signal meter) ? quadrature detection ? af preamplifier ? agc output ? band muting ? weak input muting ? soft muting adjustment pin ? muting attenuation adjustment pin ? if counter buffer output (also used for am) ? sd (if counter buffer on level) adjustment pin ? sd output (active high) (also used for am) noise canceller ? high-pass filter (first order) ? delay circuit based low-pass filter (fourth order) ? noise agc ? pilot signal compensation circuit ? noise sensitivity setting pin ? function for disabling the noise canceller in am mode multiplex functions ? adjustment-free vco circuit ? level follower type pilot canceller circuit ? hcc (high cut control) ? automatic stereo/mono switching ? vco oscillation stop function (am mode) ? forced monaural ? snc (stereo noise controller) ? stereo display pin ? anti-birdie filter am ? double balanced mixer (1st, 2nd) ? if amplifier ? detection ? rf agc (narrow/wide) ? pin diode drive pin ? if agc ? signal meter output (also used for fm) ? local oscillator circuits (first and second) ? local oscillator buffer output ? if counter buffer output (also used by the fm if) ? sd (if counter buffer on level) adjustment pin ? sd output (active high) (also used for am) ? wide agc ? detection output frequency characteristics adjustment pin (low cut, high deemphasis) ? am stereo buffer mrc (multipath noise rejection circuit) am/fm switching output (linked to the fm v cc ) no. 6655- 4 /54 la1787m
operating characteristics and symbols used in the test circuit diagrams switches (sw) switch on = 1, sw off = 0 there are two switches that use signal transfer. sw2: switches between the mixer input and the if input. sw4: switches between noise canceler input and if output + noise canceler input. no. 6655- 5 /54 la1787m types of sg used pg1 (ac1) used for noise canceler testing. a pulse generator and an af oscillator are required. ac2 used for fm front end testing. outputs an 83 mhz signal. ac3 used for fm if, noise canceler, and mpx testing. outputs a 10.7 mhz signal. stereo modulation must be possible. ac4 used for am testing. outputs 1 mhz and 1.4 mhz signals. ac5 used with the mrc. can also be used for af and osc. power supply v cc 8 v v cc 1 5 v sd, stereo, seek/stop v cc 2 0.1 v / 0.7 v / 2 v / 4 v these levels keyed agc, mute att v cc 3 0.1 v / 0.6 v / 2 v must be variable. hcc, snc, sasc (mrc) ? trimmers (variable resistors) vr1 separation adjustment vr2 pilot cancellation adjustment ? ac voltages va1 am/fm osc buff pin 4 va2 first if output pin 53 ? cf ? pin 51 load level (10.7 mhz) va3 if counter buffer pin 23 (10.7 mhz/450 khz) va4 mpx out left ch pin 15 (af) va5 mpx out right ch pin 16 (af) test points ? dc voltages vd1 fm rf agc voltage pin 2 vd2 am/fm sd, am tweet, fm stereo indicator pin 26 vd3 am/fm s-meter pin 24 vd4 mrc output pin 27 vd5 mute drive output pin 33 vd6 am antenna damping voltage pin 46 vd7 n.c. gate time pin 8 ? switches parameter on off sw1 am/fm switching. the fe v cc is supplied to pin 62. fm am sw2 fm if switching. pin 51/fe output fe if out (a) ac3 (b) sw3 for conversion gain testing conversion gain measurement (a) other/purposes sw4 for switching between noise canceler input and if output + noise canceler. ac1 (a) other/purposes sw5 high-speed sd high-speed sd other/purposes sw6 seek/stop (if buff on/off) stop seek (if buffer output) sw7 mute att 200 k mute 200 k off sw8 mute att 30 k mute 30 k off sw9 for pilot cancellation testing when pilot cancellation is used when pilot cancellation is not used sw10 mute off (pin 33) mute off mute on
pin no. function description equivalent circuit 3 f.e.gnd 7 v cc a l c a13558 pin descriptions no. 6655- 6 /54 la1787m 1 ant 1000pf 1000pf 100 100 300 v cc 62 pin rf agc a13555 + 2 n agc det w agc det keyed agc ant damping driver v cc v cc 12k fet 2nd gate a13556 4 v cc 25pf 20pf 2k v t a13557 an antenna damping current flows 1 antenna damping drive when the rf agc voltage (pin 2) reaches v cc C v d . 2 rf agc used to control the fet second gate. 4 osc oscillator connection am first oscillator 7 am osc this circuit can oscillator up to the sw band. an alc circuit is included. continued on next page .
no. 6655- 7 /54 la1787m pin no. function description equivalent circuit 13 pilot input pin 13 is the pll circuit input pin. 14 n.c, mpx, mrc, gnd ground for the n.c., mpx, and mrc circuits. + 8 9 3k 15k 3k 3k 1m 0.01 f 0.47 f 200 a13559 13 12 11 v cc 3.9k 0.01 f 6800pf lpf differential amp gate circuit a13560 12 13 30k v cc pll n.c 0.01 f a13561 after setting up the medium field (about 50 db ) sensitivity with the 8 noise agc sensitivity noise sensitivity setting pin (pin 8), 9 agc adjustment set the weak field (about 20 to 30 db ) sensitivity with the agc adjustment pin (pin 9) 11 memory circuit connection recording circuit used during 12 noise canceller operation. continued from preceding page. continued on next page.
no. 6655-8/54 la1787m pin no. function description equivalent circuit 15 3.3k 3.3k v cc 0.015 f 0.015 f 16 a13562 17 18 v cc 20k 10k 0.01 f 100k 6.7k a13563 17 18 v cc 0.01 f 1.5k 100k a13564 15 mpx output (left) deemphasis 16 mpx output (right) 50 s: 0.015 f 75 s: 0.022 f adjustment is required since the pilot signal level varies with the 17 pilot canceller signal output sample-to-sample variations in the if output level and other parameters. 18 pilot canceller signal output pin 18 is the output pin for the pilot canceller signal. continued from preceding page. continued on next page.
no. 6655- 9 /54 la1787m pin no. function description equivalent circuit 20 vco the oscillator frequency is 912 hz. kbr-912f108 (kyocera corporation) csb-912jf108 (murata mfg. co., ltd.) 19 5k decoder composite signal 30k 4k 0.047 f a13565 20 csb 912 jf108 v ref 10pf a13566 + + + 21 22 15k 15k 19k v ref a13567 use a trimmer to adjust the 19 separation subdecoder input level. adjustment pin (the output level is not modified in mono and main modes.) 21 phase comp. 22 phase comp. continued from preceding page. continued on next page .
no. 6655- 10 /54 la1787m pin no. function description equivalent circuit 23 + + + 4.9v 50k 150 50f 1.3v 10k 51k stop if buff. forced sd: 2.5v seek 5v sd sw v cc am mute if counter buffer a13568 32 24 10k 10k v cc am/fm sw fm s-meter am s-meter outputs a 1-ma current during am reception am/fm sw mrc a13569 26 100k v dd am/fm sd stereo indicator seek/stop switching a13570 continued from preceding page. continued on next page. this pin functions both as the if counter buffer (ac output) and as the seek/stop switch pin. the voltage v23 switches between the following three modes. 23 if counter buffer seek/stop during fm reception: switching 5 v: seek mode 2.5 v: forced sd mode 0 v: reception mode am reception (two modes: 0 and 5 v) 5 v: seek mode 0 v: reception mode 24 am/fm signal meter fixed-current drive signal meter output in am mode, pin 32 outputs a 32 dedicated fm signal meter 1-ma current. thus the hcc circuit is turned off. the voltage v23 switches between three modes as follows. fm reception: 5 v: the sd pin operates linked to the if counter buffer. 26 stereo indicator for the sd pin 2.5 v: forced sd mode: operates as the sd pin. 0.7 v: reception mode: stereo indicator am reception: (two modes: 0 and 5 v) 5 v: operates as the seek sd pin. 0 v: reception mode. not used.
no. 6655- 11 /54 la1787m pin no. function description equivalent circuit + 27 2 a 100 c2 v cc v cc pin 28 a13571 28 v ref a13572 + 32 1 f 29 v ref a13573 continued from preceding page. continued on next page. the mrc detector time constant 27 mrc control voltage time is determined by a 100 resistor constant and c2 when discharging and by the 2- a current and c2 when charging. 28 snc control input the sub-output is controlled by a 0 to 1-v input. the high band frequency output is controlled by a 0 to 1-v input. it can also be controlled by the 29 hcc control input mrc output. use a resistor of at least 100 k when controlling with the pin 32 fm s-meter signal.
no. 6655- 12 /54 la1787m pin no. function description equivalent circuit 31 30 + v cc v cc 10k fm detector output am detector noise canceller 1 f 50k 4.2v a13574 + 32 v cc 10k 1k 1 f a13575 mrc input + 33 hole det soft mute band muting seek off v cc 0.1 f c1 50k 10k 50k mute amp. sd circuit a13576 continued from preceding page. continued on next page. 30 noise canceller input pin 30 is the noise canceller input. the input impedance is 50 k . pin 31 is the am and fm detector output in fm mode, this is a low- impedance output. 31 am/fm detector output in am mode, the output impedance is 10 k . to improve the low band separation, use a coupling capacitor of over 10 f. fm s-meter output block 32 if s-meter output and mrc mrc ac input block dc input adjust the external 1-k resistor to attenuate the mrc ac input and control the circuit. ? the muting time constant is determined by an external rc circuit as described below. attack time: t a = 10 k c1 release time: t r = 50 k c1 ? noise convergence adjustment 33 mute drive output the noise convergence can be adjusted when there is no input signal by inserting a resistor between pin 33 and ground. ? muting off function ground pin 33 through a 4-k resistor.
no. 6655- 13 /54 la1787m pin no. function description equivalent circuit 37 36 35 34 hole det quadrature detector band muting if limitter amplifier a13577 0.1 f v ref r1 r2 v cc v cc c 390 1k 3pf 24 38 + sd comparator s-meter r sd adj 130 a a13578 24 39 + keyed agc comparator s-meter a13579 6.4k 3.6k 1.3v 50pf 150 90 a v cc am if out continued from preceding page. continued on next page. ? the resistor r 1 determines the width of the band muting function. increasing the value of r 1 narrows the band. reducing the value of r 1 widens the band. 34 agc 35 qd output ?null voltage 36 qd input when tuned, the voltage between 37 v ref pins 34 and 37, v 34 C 37 , will be 0 v. the band muting function turns on when |v 34 C 37 | 3 0.7 v. v 37 = 4.9 v a 130- a current flows from pin 38 fm sd adj 38 and, in conjunction with the external resistance r, determines the comparison voltage. the keyed agc operates when the voltage created by dividing the pin 24 s-meter output voltage by the 6.4 and 3.6 k resistors 39 keyed agc becomes lower than the voltage am stereo buffer determined by the resistor between pin 39 and ground. this pin also is used as the am stereo if buffer pin.
no. 6655- 14 /54 la1787m pin no. function description equivalent circuit 41 a13580 + 2200pf 20k 20k v cc 42 + det v cc v cc c 50k 50k 1k 1k a13581 + 43 + v cc 30k 30k 30k 19khz e 0 bias 1 f a13582 continued from preceding page. continued on next page. the hcc frequency characteristics 41 hcc capacitor are determined by the external capacitor connected at this pin. this pin is used to change the frequency characteristics of the unneeded audio band under 100 hz in am mode to produce a clear audio signal. note: the lc capacitor must be connected between this pin and v cc (pin 40). 42 am l.c. pin this is because the detector circuit operates referenced to v cc . the cutoff frequency f c is determined by the following formula. f c = 1/2 p 50 k c inserting a 1-m resistor between 43 pilot detector pin 43 and v cc will force the ic to mono mode.
no. 6655- 15 /54 la1787m pin no. function description equivalent circuit 45 if output the if amplifier load + 42 det 44 v cc v cc c 2.2 f 0.022 f 50k 50k 240k g1 10 seek on if agc a13583 45 det pin 40 v cc pin 40 v cc a13584 46 v cc v cc 50pf 100 20k ant damping driver w.agc amp. a13585 continued from preceding page. continued on next page. g1; used for time constant switching during seeks. ? reception t = 2.2 f 300 k 44 if agc ? seek t = 2.2 f 10 the external capacitors are connected to v cc . this is because the if amplifier operates referenced to v cc . am antenna damping i 46 = 6 ma (maximum) 46 drive output this is the antenna damping wide band agc input current.
no. 6655- 16 /54 la1787m pin no. function description equivalent circuit 52 if input the input impedance is 2 k . 47 + v cc 30k r 140 a pin 24 mute inverter a13586 + 48 + 57 + v cc 5.6v 10k antenna damping 3.3 f 47 f for agc use a13587 50 51 2.6v 10k 10k 0.022 f 330 if in a13588 52 2k 100 a13589 continued from preceding page. continued on next page. fm muting on level modify the value of the external 47 adjustment resistor to adjust the muting on level. rf agc rectification capacitor the low frequency distortion is determined as follows: increasing c48 and c57 improves 48 rf agc bypass the distortion but makes the 57 rf agc response slower. reducing c48 and c57 aggravates the distortion but makes the response faster. 50 if bypass 51 fm if input due to the high gain of the limiter amplifer, care must be taken when choosing the grounding point for the limiter amplifer input capacitor to prevent oscillation.
no. 6655- 17 /54 la1787m pin no. function description equivalent circuit 53 56 if out if in 2.75v 300 v cc 300 a13590 54 49 osc pin 40 v cc pin 40 v cc 330 a13591 55 58 + w-agc n-agc 62 pin v cc 30pf 50pf 50 a signal meter am sd c1 c2 mix in mix out a13592 continued from preceding page. continued on next page. ? input and output pin or the first if amplifier ? inverting amplifier 53 if amplifier output v56 = 2 v 56 if amplifier input input impedance: r in = 330 v53 = 5.3 v output impedance r out = 330 the mixer coil connected to the 54 mixer output: 130 a pin 54 mixer output must be 49 mixer input wired to v cc (pin 40). the pin 49 mixer input impedance is 330 pins 55 and 58 include built-in dc cut capacitors. the agc on level is determined by the values of the capacitors c1 and c2. 55 w-agc in pin 55 functions as the sd am sd adj sensitivity adjustment pin in am mode. 58 n-agc in muting attenuation the output current i55 is 50 a, adjustment pin and v55 varies depending on the value of the external resistor. the sd function operates by comparing v55 with the s-meter voltage.
no. 6655- 18 /54 la1787m pin no. function description equivalent circuit 59 60 63 o s c 64 1st.if 30 v cc c1 c2 5pf 5pf rf amp 620 620 v cc a13593 + 3 6 + fm.f.e agc am/fm switching circuit sd v cc 510 100k 3.3v gnd a13594 8v 62 am 1st mix to rf amp. 10k 2.1v a13595 10 10k 5.6v 20pf 33pf x tal to 2nd mix a13596 continued from preceding page. double balanced mixer pins 59 and 60 are the mixer 10.7-mhz output 59 mixer output pins 63 and 64 are the mixer 60 input. this is an emitter insertion type circuit, and the amount of 63 mixer input insertion is determined by the 64 capacitors c1 and c2. note: the lines for pins 63 and 64 must be kept separated from the lines for pins 59 and 60. pin 6 functions both as the fm front end v cc and the am/fm switching circuit. 6 front end v cc am/fm switching 1st mix first mixer input 62 input the input impedance is about 10 k . crystal oscillator circuit 10 am 2nd osc the kinseki, ltd. hc-49/u-s and a c l of 20 pf must be used. v6 voltage mode when 8 v ? fm open ? am
block diagram no. 6655- 19 /54 la1787m 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 48 47 46 45 44 43 42 41 40 39 38 37 36 35 34 33 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 64 63 62 61 60 59 58 57 56 55 54 53 52 51 50 49 ant d buff am 1st osc agc amp noise pican input trig gate counter amp hpf ff 19k<90k lpf snc mrc ff 19k<0 ff 38k<0 ff phase comp vco trig pilot det p-can sub dec mat rix vco stop main hc hcc ant d hole det mute drive amvsm am sd if buff fmvsm if limiter amplifier fm sd det if agc buff l.c. osc buff osc dc-c det afc clamp q.det mute amp mix am/fm mix rf agc wb agc tweet buff am fm vref seek sw sd/st ind keyed agc if reg am/fm sw w.b.agc rf agc amp input + + + + + + + + + + + + + + + + + ant d osc rf agc fe gnd 30k 10k 30k 2k 18pf 300pf 6800pf 0.01 f 0.015 f 0.015 f 0.01 f 0.22 f 0.47 f 1 f 1 f 1 f am hc am level 1 f 1 f 20k 100k 5.6k 10k 100k 8200pf 50k 1k 100k 0.047 f 10.26mhz 10pf 5pf 25pf 20pf 18pf 1 f 0.022 f 0.022 f 0.022 f 0.01 f 0.47 f 1m + am osc mpx out pi.can adj sep.adj csb912jf108 am/fm s-meter gnd 5v snc hcc nc-in det out meter fm gnd nc mpx gnd n.c.mpx gnd mute drive 0.47 f 0.47 f 0.22 f 0.022 f 2.2 f 3.3 f 1 f 11k if7 100 f 2200pf afc in qd out qd in v ref fm sd adj. am lc chcc pilot det keyed agc 10k 10k 30k 240k 6.8k 0.1 f rfagc gnd v cc 0.022 f 0.022 f 0.022 f 100 h 47 f 15pf 15pf 15pf 100 h 0.022 f 30 100k 1k 510k 20k 2.7k 62pf 330 fc18 antd 1mh 30mh fm if in fm if out am if in fe if in 0.022 f 220 100 am mix out fm wb agcin am sd adj mute att fev cc 0.022 f 5pf 5pf 8pf 18pf 30 30 30k 100k 180 9pf 39pf 100k 1000pf 100k 100 gnd 200k 1000pf 3sk263 0.1 f 0.022 f gnd 1000pf 1000pf 30k 22pf 22pf 0.022 f 100k v cc v cc 100f 0.022 f fmif am gnd fmif am nc mpx v cc fm/am vsm right ch. left ch. am/fm osc buff fm gnd fm/am vt fm ant in am rf gnd am ant in am v cc seek ? am/fm sd stop ? fm st ind. 0.022 f to am stereo (if out) adj + + + + + + + + 100k 100k 10k 10k 10k 2.2k 0.01 f 3sk583 1 f 22pf 22pf 7.2mhz 10 f 0.22 f 100pf 100pf 100pf 100pf 51k 0.22 f 200k 1k 68pf 2.2k 4.7k 51k 10 f 10 f 10 f 10 f 240k 240k 22k 22k 22k 22k 22k 22k 1k 10k 10k 1k 100k 100k 1.5k 100 f 100 f 5.6v 9.1v 100pf ci cl do rds adc mute r on sd/mono st ce lc867148 +b 12v l a13597 r v ss pd v dd fm in ci cl do fm/am ce am in lc7216m 20 19 18 17 16 15 14 13 12 11 1 2 3 4 5 6 7 8 9 10
ac characteristics test circuit no. 6655- 20 /54 la1787m 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 48 47 46 45 44 43 42 41 40 39 38 37 36 35 34 33 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 64 63 62 61 60 59 58 57 56 55 54 53 52 51 50 49 ant d buff am 1st osc agc trig gate hpf ff 19<90 k lpf snc mrc ff 19<0 ff 38k<0 ff phase comp vco trig pilot det p-can sub dec ma trix vco stop main hc hcc ant d hole det mute drive amvsm am sd if buff fmvsm fm sd det if agc buff l.c. osc buff osc dc-c det afc ciamp q.det mute amp mix am/fm mix rf agc w.b. agc tweet buff am fm vref keyed agc ff reg fm/am sw w.b.agc rf agc + + + + + + + + + + + + + + + + ant d rf agc fe gnd osc 20k sw1 va1 va9 8v v cc va6 10k 20pf 300pf 6800pf 0.01 f 10 f 0.015 f 0.015 f 0.01 f 0.22 f 0.47 f 1 f b a sw4 (t) 1 f am hc am level 1 f 1 f 20k 20k 3pf 100k vr1 vr2 8v sw9 5.6k 8200pf 0.047 f 0.022 f 10.26mhz x tal 5pf 25pf 20pf 1 f 0.022 f 0.022 f 0.01 f 0.47 f 1m 50k 50k vd2 va3 fm/am ifbuff. vd4 sw5 4.3k 100k 100k + am osc mpx out pi.can adj sep. adj csb912jf108 am/fm s-meter gnd snc hcc nc-in det out fm s-meter n.c.mpx gnd mute drive 0.1 f 0.47 f 0.22 f 0.022 f 2.2 f 3.3 f 1 f 15k 180k if7 100 f 2200pf afc in qd out qd in v ref fm sd adj. am lc chcc pilot det mute or adj keyed agc 10k 10k 22k 240k 6.8k 0.1 f rfagc if out b a if in sw3 sw2 ( i ) mix gnd v cc 0.022 f 0.022 f 100 h 47 f 20k 0.022 f 100 h 0.022 f 30 100k 1.6k 510 30 25 50 10pf 330 fc18 antd vd6 sw8 sw7 1mh 6.8mh fm if in fm if out am if in fe if in 330 200 0.022 f 18pf am mix out fm wb agcin am sd adj mute att fev cc v cc 5pf 5pf 3pf 39pf 100k 50 10k 1m 100 100 gnd vt 0.022 f 0.022 f 1000 f 0.022 f 15pf jis dummy 30 50 65pf 30k right ch. left ch. am/fm osc buff va2 fm gnd fm v cc seek ? am/fm sd stop ? am st buffer fm st ind. adj vd1 200k 30k v cc 2 vd3 v cc 2 vd5 mrc-in v cc 8v v cc 3 hcc nc-in snc pg1 (ac1) + v cc 1 5v 100k sw6 + + ac5 + ac1 sg1 300 50 50 + ac3 sg3 + ac2 sg2 a13598 3pf 0.022 f 10k 10k v cc va7 8v sw10 10 f + 10k 1m va8 if limiter amplifier
no. 6655- 21 /54 la1787m parameter symbol switch states sw1 sw2 sw3 sw4 sw5 sw6 sw7 sw8 sw9 sw10 current drain i cco -fm on b off b on off off on demodulation output v o -fm on b off b on off off on pin 31 demodulation output v o -fm31 on b off b on off off on channel balance cb on b off b on off off on total harmonic distortion (fm) thd-fmmono on b off b on off off on signal-to-noise ratio: if s/n-fm if on b off b on off off on am suppression ratio: if amr if on b off b on off off on att-1 on b off b on off off on muting attenuation att-2 on b off b on off off on att-3 on b off b on off off on separation separation on b off b on off off on stereo on level st-on on b off b on off off on stereo off level st-off on b off b on off off on main total harmonic distortion thd-main l on b off b on off off on pilot cancellation pcan on b off b on off off off/on snc output attenuation attsnc on b off b on off off on hcc output attenuation 1 atthcc-1 on b off b on off off on hcc output attenuation 2 atthcc-2 on b off b on off off on input limiting voltage vi-lim on b off b on off off on on muting sensitivity vi-mute on b off b on off off on sd sensitivity 1 sd-sen1 fm on b off b off off off off on sd sensitivity 2 sd-sen2 fm on b off b on off off off on if counter buffer output v ifbuff-fm on b off b off off off off on v sm fm-1 on b off b on off off on signal meter output (fm) v sm fm-2 on b off b on off off on v sm fm-3 on b off b on off off on v sm fm-4 on b off b on off off on muting bandwidth bw-mute on b off b on off off on mute drive output v mute-100 on b off b on off off on n-agc on input v nagc on a on b on off off w-agc on input v wagc on a on b on off off conversion gain a.v on a on b on off off oscillator buffer output v oscbufffm on a on b on off off gate time 1 t gate1 on off a on off off noise sensitivity sn on off a on off off nc effect sn-nc on/off off a on off off mrc output v mrc on off b on off off mrc operating level mrc-on on off b on off off practical sensitivity s/n-30 off off b on on detection output v o -am off off b on on pin 31 detection output v o -am31 off off b on on agc f.o.m. v agc-fom off off b on on signal-to-noise ratio s/n-am off off b on on total harmonic distortion (am) thd-am off off b on on signal meter output (am) v sm am-1 off off b on on v sm am-2 off off b on on oscillator buffer output v oscbuff am-1 off off b on on wide band agc sensitivity w-agcsen 1 off off b on on w-agcsen 2 off off b on on sd sensitivity sd-sen1 am off off b off off sd-sen2 am off off b off off if buffer output v ifbuff-am off off b off off test conditions
usage notes 1. notes on v cc and ground * : when applying the v cc voltage to pin 6, that voltage must not exceed the pin 40 and pin 61 v cc voltages. (this condition must be checked carefully when first applying the pin 6 voltage.) 2. notes on am coil connection the v cc used for the first oscillator coil connected to pin 7 must be at the same potential as pin 61. connect to the ift connected with pin 45, and to the mix coil connected with pin 54. v cc must be at the same potential as pin 40. 3. am/fm switching pin 6 is also used as the fm front end and rf agc v cc no. 6655- 22 /54 la1787m pin 40 v cc for the fm if, am, nc, mpx, and mrc blocks pin 25 ground for the fm if and am blocks pin 14 ground for the nc, mpx, and mrc blocks pin 61 v cc for the fm front end, am first mixer, and first oscillator blocks * pin 6 v cc for the fm front end and agc blocks, and the am/fm switching pin pin 3 ground for the fm front end, first mixer, and first oscillator blocks pin 6 voltage mode 8 fm open am fig. 1 la1787m overview 1. notes on the la1781m, la1784m, and la1787m the la1784m is a version of the la1781m that uses an external oscillator circuit, and has the same characteristics as the la1781m. the la1787m is a version of the la1784m that features improved characteristics. la1781m la1784m la1787m this product is a version of the la1781m with the oscillator circuit removed. it supports the use of an external oscillator circuit. it has the same characteristics as the la1781m. the la1787m features improved characteristics over the la1781m and la1784m.
no. 6655- 23 /54 la1787m 2. modified circuits the following characteristics have been improved over those of the the la1784m. ? the am adjacent channel interference characteristics ( ? 40 khz) have been improved. ? the am s-meter curve slope has been increased. ? the fm separation temperature characteristics have been improved. ? the stereo indicator sensitivity has been improved. ? the fm oscillator circuit has been omitted. (1) am interference characteristics improvement the second signal interference and suppression have been improved for adjacent channels ( 40 khz) by increasing the am second mixer input dynamic range. (2) the am s-meter curve slope has been increased. the slope of the am s-meter curve has been increased from that of the la1781m and la1784m. ?0 0 0 2 3 4 5 6 7 1 20 40 60 80 100 120 140 la1787m la1780m la1781m am s-meter voltage antenna input ?db s-meter voltage ?v (3) fm separation temperature characteristics improvement the temperature characteristics have been improved, the amount of change in the separation due to drift when at power on has been stabilized. this makes it easier to adjust the separation. 35 40 45 50 55 60 0 1 2 3 35 40 45 50 55 60 0 1 2 3 change in separation (la1781m): first if input time after power on ?minutes change in separation ?db change in separation (la1787m): first if input time after power on ?minutes change in separation ?db
no. 6655- 24 /54 la1787m (4) stereo indicator sensitivity improvement the stereo indicator sensitivity (on/off) is equivalent to that of the la1780m stereo on level stereo off level la1781m/1784m 4.1% 3.1% la1787m/1780m 2.6% 1.6% * : the pilot level such that the stereo indicator goes on or off for a 10.7 mhz unmodulated if input. (5) fm oscillator circuit removed the internal fm oscillator circuit provided in the la1781m has been removed. the fm oscillator level can be adjusted by constructing an external circuit block. *: however, this requires 4 more external parts than the la1781m: 1 transistor and 3 resistors/capacitors. 4 vt v cc v cc a13600 4 vt v cc ic internal ic internal a13601 la1787m/1784m fm osc la1780m/1781m fm osc 3. gain distribution the table below shows the gain distribution of the la1780m, la1784m, and la1787m. (these are measured values.) compared to the la1784m, the total gain is lower. 1st mix (10.7) 1st if (10.7) 2nd mix (450) 2nd if (450) la1780m 10 db 3.3 db 3.2 db 69 db la1784m 7.5 db 13 db 7 db 66 db la1787m 7.5 db 3.5 db 8.6 db 67 db first mixer : no circuit changes from the la1784m. first if amplifier : equivalent to the la1780m circuit. (the gain is lower than that in the la1781m and la1784m.) second mixer : the mixer circuit has been modified to improve adjacent channel suppression and interference. second if amplifier : equivalent to the la1780m circuit. (typical value)
no. 6655- 25 /54 la1787m 4. changes to applications component values that change from la1781m/la1784m applications (since the total am gain has changed in the la1787m) ? am sd adjustment resistor (pin 55): because vsm is higher. ? am level adjustment resistor (pin 31): since the post-detection audio amplifier gain is higher than in the la1781m and la1784m, the output level is also higher. this resistor must be changed to match the set value. ? am mixer coil (pin 54), ift coil (pin 45) damp resistor: since the if block gain is increased, the mixer (pin 54) and ift (pin 45) coil damping must be adjusted. ? separation adjustment resistor (pin 19): since an internal 4 k resistor has been added to the pin 19 input circuit to improve the separation temperature characteristics, the value of the external resistor must be reduced from that used with the la1780m, la1781m, and la1784m. (see the following page.) 19 30k 0.047 f decoder composite sign 19 30k added 4 k resistor 5k 0.047 f decoder composite sign 5k a13602 a13603 la1781m/1784m la1787m 1. notes on the fm front end notes on interference rejection characteristics ? intermodulation characteristics the la1787m applies two high-band agc functions to prevent im (the generation of intermodulation). these are the narrow agc (pin 58: mixer input detection type) and the wide agc (for the pin 55 input), and this results in the antenna frequency characteristics shown in figure 2. the levels at which the agc functions turn on are determined by the capacitors attached at pins 55 and 58. ? ? ? ? ? 0 50 70 80 90 100 110 60 1 2 3 4 5 when ? f = 0, 98.1 mhz the wide agc sensitivity when pin 39 is 5 v. agc sensitivity ?db ? f ? mhz ? f ? agc sensitivity the narrow agc sensitivity when pin 39 is at ground. fig. 2 functions
no. 6655- 26 /54 la1787m ? notes on second-channel attenuation suppression keyed agc (3d agc) is a technique for achieving good characteristics for both intermodulation and second- channel attenuation at the same time. when the desired signal is faint or nonexistent, the high-band agc level will be essentially 0, and as a result automatic tuning may malfunction and blocking oscillation may occur in the presence of strong interfering stations. keyed agc helps resolve these problems. this 3d agc technique uses information that has the following three frequency characteristics and is a unique sanyo-developed system for determining the high-band agc level. rf and ant circuit information: mixer input agc mixer circuit information: mixer output agc cf selectivity information: s-meter output 4 5 2 3 1 0 50 70 80 90 100 110 60 1 2 3 4 5 pin 58 capacitor: 10 pf narrow agc on level db ? f mhz ? f agc on level (ant input) pin 58 capacitor: 47 pf 39 keyed agc fig.3 140 130 120 110 100 90 80 70 7 1.0 2 3 5 7 10 2 3 5 7 100 2 3 5 wide agc on level frequency characteristics narrow agc on level frequency characteristics agc input level frequency characteristics such that v rf agc (pin 2) falls under 2 v. pin 59 narrow agc and pin 55 wide agc input levels ?db frequency, f ?mhz w-agc, n-agc ? f fig.5 4 5 2 3 1 0 50 60 70 80 90 100 110 1 2 3 4 5 pin 55 capacitor: 3 pf pin 55 capacitor: 10 pf wide agc on level db ? f mhz ? f agc on level (ant input) 39 5v keyed agc fig.4 ? 3d agc features feature merit only the narrow agc sensitivity (operation at ? f < 1.5 mhz) is ? effective in resolving second-channel attenuation problems. controlled by the field strength of the desired station. the narrow agc sensitivity is controlled by a voltage (v 23 ) that is ? allows effective resolution of second-channel attenuation problems without under 0.5 v. degrading three-signal characteristics. ? seek operations may stop incorrectly due to the occurrence of the wide agc can operate even when v 23 = 0 (when the desired intermodulation. station is not present). ? it is possible to prevent the occurrence of intermodulation in the rf tuning circuit and antenna in the presence of strong interfering stations, and blocking oscillation due to agc operation can be prevented. the narrow and wide agc sensitivities can be set independently. ? settings can be optimized for the field conditions. (see figure 3 and 4.) the system has two agc systems: narrow and wide agc. ? since the narrow agc operates for the desired station and adjacent (see figure 5.) stations, the wide agc sensitivity can be lowered and agc malfunction due to local oscillator signal can be prevented.
3d agc sensitivity characteristics no. 6655- 27 /54 la1787m second-channel atten uation impro v ement desired station a gc sensitivity 4 3 2 1 ? f narro w a gc sensitivity v 23 (desired station field strength) wide a gc sensitivity a gc sensitivity a12075 3d agc sensitivity ? f, v 23 characteristics ? the wide agc sensitivity is determined by the antenna and rf circuit selectivity, regardless of v 23 . ? the narrow agc sensitivity is determined by the following. the total selectivity of the antenna, rf circuit, and mixer when v 23 3 0.5 v the above selectivity and v 23 when v 23 < 0.5 v ? the improvement in the second-channel attenuation corresponds to the area occupied by the narrow agc in the total agc sensitivity area. figure 8 on the next page shows the actual operation of the circuit. 4 5 2 3 1 0 50 60 70 80 90 100 110 1 2 3 4 5 the fu input level at which antenna damping turns on db ? f mhz ? f agc on level (ant input) a12076 ant in v in second-channel pad f d = 98.1 mhz fu = 98.1 mhz + ? f fig. 6 fig. 7
notes on 3d agc (keyed agc) ? the antenna damping current from the pin due to the pin diode flows when the v2 pin reaches the v cc - v be level. ? the narrow agc operates as follows. when pin v39 > pin v24: the narrow agc turns off. when pin v39 < pin v24: the narrow agc turns on. no. 6655- 28 /54 la1787m + 55 w-agc det 58 1 2 39 24 n-agc det + + v cc v cc ant dumping 90 a s-meter vs-meter a11763 fig. 8
? the la1787m includes two agc circuits in its front end block. antenna input limiter using a pin diode. fet second gate control the agc input pin is pin 59, and the agc circuit turns on when a signal of about 30 mvrms is input. agc activation the pin diode drive circuit turns on when v cc C v2 is greater than or equal to about 1 v, and input limitation is applied to the antenna circuit. in application circuits, there will be an attenuation of about 30 to 40 db. next, when an adequate current flows in the antenna attenuator pin diode, the inductance falls, the fet second gate voltage drops, the fet gm falls, and the agc operates. the recommended fet is the sanyo 3sk263, which is an enhancement-type mosfet. therefore, full agc is applied when the voltage, v g2-s , between the second gate and the source is 0. note that if a depletion-type mosfet is used, agc will not be applied unless v g2-s is less than 0. no. 6655- 29 /54 la1787m 0 1 2 3 4 5 6 7 8 9 ?0 0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 fr = 98.0 hz v cc = 8 v ta = 25 c range where the agc does not operate agc level due to the mosfet second gate: about 35 db agc level due to the pin diode: about 35 db v2agc v ant in db v2 agc characteristics fig.9 59 64 60 63 62 osc a12077 mix input mix out mix out mix input mix v cc mix mixer circuit ? mixer the mixer circuit in this ic is a double-balanced mixer with both balanced input and balanced output. input circuit type emitter input input impedance: 25 due to optimized device geometry, emitter current, the bias, this ic achieves the following performance. mixer input usable sensitivity: 15 db mixer input imqs: 90.5 db (for an oscillator level of 200 mvrms) * the mixer input imqs is defined as: fr = 98.8 mhz, no input fu1 = 98.8 mhz, 1 khz, 30% modulation fu2 = 99.6 mhz, no modulation the interference 1 and 2 input levels such that generated intermodulation output signal-to-noise ratio becomes 30 db when an interference signal with the same level as the mixer input is input, and distortion occurs in the mixer. fig. 10
? oscillator figure 11 shows the type of oscillator circuit used in this ic. it includes both an oscillator and an oscillator buffer. no. 6655- 30 /54 la1787m 5 4 vt 18pf 25pf 20pf v cc am/fm osc buffer out a12078 56 53 + to mix 330 330 330 fm if input a12079 ? figure 12 shows the type of fm first if amplifier used in this ic. it is a differential single-stage amplifier. specifications input impedance: 330 output impedance: 330 gain: 20 db fig. 11 fig. 12
2. fm if ? notes on the fm sd and sd adjustment the figure below presents an overview of the fm sd and the if count buffer. no. 6655- 31 /54 la1787m s-meter fm if hole clet muting drive output stereo ind band muting 39 24 33 23 26 + + + 4.9v r r r if count buffer if count output 2.5v 5v sd stereo/mono 5v a11759 v 23dc v 23ac v 26 v 33 v 38 v 24 5 v larger values of r 33 smaller values of r 33 s-meter v 33 over 0.7 v v 33 over 0.7 v on as an sd signal sd on sd on stereo mono 0.7 v off off if count buffer 5 v 2.5 v 0 v if counter output off rds and other types of sd detection can be used by switching these modes. a11758 for stereo input (when the v26 pin voltage is 0.7 v), when this pin is shorted to ground (0.1 v or lower) the ic will operate in forced mono mode. new la1784m functionality: fig. 13 fig. 14 figure 14 shows the relationship between the fm sd, the if count buffer output, the s-meter, and the muting drive output.
? transient response characteristics during automatic tuning the transient characteristics for sd and if count buffer on/off operation are determined by the time constants of the rc circuits attached to the following pins. (1) muting time constant: pin 33 (2) s-meter time constant: pin 24 (3) afc time constant: pin 34 there are two points that require consideration when using fast tuning. (1) the sd time constant due to the s-meter time constant since the current i24 (pin 24) varies with the field strength, the time constant also changes. there is no hysteresis in the comparator. if a smaller value is used for c24, you must select a value for c such that the agc does not become unstable when the pin 24 voltage is used for keyed agc. (2) the sd time constant due to the pin 33 muting voltage time constant the changes in volume due to field fluctuation during weak field reception can be made smoother by setting the attack and release times during soft muting operation. no. 6655- 32 /54 la1787m 24 s-meter c 24 a12080 10k mute amp mute drive 10k 50k c 33 a11766 33 attack release 0 10 20 30 40 50 6 10 14 18 22 26 30 34 antenna input such that pin 5 goes high db resistance between the pin and ground k sd sensitivity adjustment fig.17 fig. 15 fig. 16 muting time constants attack: 10 k c33 release: 50 k c33
however, when testing this stop sensitivity, note that when checking the waveform on the if count buffer output (pin 23), there are cases, such as that shown below, where current in the test system may be seen as flowing to ground and cause oscillation that causes the if count buffer output to go to the output state. ? fm muting control pin (pin 47) (r47: 30 k variable resistor) the C3 db limiting sensitivity can be adjusted with r47. ? fm muting attenuation adjustment (pin 58) the muting attenuation can be switched between the three levels of C20, C30, and C40 db by the resistor inserted between pin 58 and ground. (note that the exact values depend on the total tuner gain.) the noise convergence with no input is determined by the pin 58 voltage. the attenuation can be set by making r33 smaller as listed in the table above. no. 6655- 33 /54 la1787m if buffer amp if f.e. 5 v 0.022 f the 10.7 mhz feeds back through ground. test system capacitance a12081 f m s o f t m u t i n g ( 1 ) a n t e n n a i n p u t d b o u t p u t n o i s e d b d e t o u t n o i s e 1 5 k 1 0 k 2 0 k r 4 7 = 7 . 5 k f i g . 1 9 58 100 r 58 a11764 r 33 a11765 33 fig. 18 fig. 20 r58 mute att open C20 db 200 k C30 db 30 k C40 db output, noise db
no. 6655- 34 /54 la1787m f m s o f t m u t i n g ( 2 ) f m s o f t m u t i n g ( 3 ) a n t e n n a i n p u t d b a n t e n n a i n p u t d b o u t p u t n o i s e d b o u t p u t d b o u t p u t d b 1 0 k 1 0 k 2 0 k 2 0 k 1 5 k 1 5 k d e t o u t d e t o u t n o i s e n o i s e r 4 7 = 7 . 5 k r 4 7 = 7 . 5 k f i g . 2 1 f i g . 2 2 2 0 0 k 3 0 k + + 58 33 31 200 k r v cc r r n-agc to mix out open 200 k 30 k mute drive limiter quadrature detector mute amp. (vca) det out a11767 20 1 0 detector output antenna input when the pin is at the ground level, the noise convergence will be 10 db and the ? db limiting sensitivity will be about 0 db . a12082 ? fm muting off function forcing this pin to the ground level turns muting off. fig. 23 fig. 24 output, noise db
? hall detection the hall detection function detects the level of the pin 36 quadrature input signal and then applies peak detection to that result. the result is output from pin 33. this circuit has three effects. (1) it assures that muting will be applied for weak inputs with an antenna input of under 5 db . the amount of attenuation is referenced to an antenna input of 60 db , fm = 1 khz, and a 22.5 khz dev output, and is variable from 10 db to 40 db when there is no input. thus one feature of this circuit is that the weak input noise attenuation and the C3 db limiting sensitivity for over 5 db inputs can be set independently. (2) when the pin 36 quadrature input is a saturated input, the pin 36 noise level (va) is detected and a peak-hold function is applied to pin 33 (vb) for locations rapid field strength variations and severe multipath occurs for fields that result in an antenna input level of over 5 db . (3) unique features one unique feature of the la1784m is that if there are adjacent stations such that f 1 = 98.1 mhz and f 2 = 97.9 mhz, a search operation will not stop at 98.0 mhz. since v afc = 0 v and v sm = 3.6 v at 98.0 mhz in the situations shown in figure 27 and 28, even though hall detection would normally not operate and sd would be high, in this ic the hall detection circuit will operate, v mute will be set to 1.2 v (over 0.7 v) and the sd signal will go low, thus preventing incorrect stopping of the search. no. 6655- 35 /54 la1787m 0 1 2 3 4 5 ?0 ?0 0 10 20 30 area muted by hall detection v 38pin ? v antenna input ? db hall detection output ?antenna input characteristics fig.25 36 33 + 0 0 0.1 f va vb a12083 fig. 26
no. 6655- 36 /54 la1787m 0 2 4 6 8 0 2 4 6 0 2 4 6 1 0 1 2 9 7 . 7 9 7 . 8 9 7 . 9 9 8 . 0 9 8 . 1 9 8 . 2 9 8 . 3 f 2 = 9 7 . 9 m h z , 1 2 0 d b f m = 4 0 0 h z , 2 2 . 5 k h z d e v . w h e n t h e t u n e r i s m o v e d i n 5 0 k h z s t e p s . w i t h a 5 1 k r e s i s t o r b e t w e e n p i n s 3 7 a n d 3 4 . w i t h t h e s d s e n s i t i v i t y a d j u s t e d t o b e 2 0 d b . f 1 = 9 8 . 1 m h z , 1 2 0 d b f m = 1 k h z , 2 2 . 5 k h z d e v . p i n 2 6 ( s d ) v p i n 2 4 , v s m v p i n 3 3 , v m u t e v v o l t a g e b e t w e e n p i n s 3 7 a n d 3 4 , v a f c v f r e q u e n c y , f r m h z u n i q u e f e a t u r e s o f t h e l a 1 7 8 4 m h a l l d e t e c t i o n c i r c u i t ( 1 ) f 1 f 2 a n t i n f i g . 2 7 0 2 4 6 8 0 2 4 6 0 2 4 6 1 0 1 2 9 7 . 7 9 7 . 8 9 7 . 9 9 8 . 0 9 8 . 1 9 8 . 2 9 8 . 3 f 2 = 9 7 . 9 m h z , 4 0 d b f m = 4 0 0 h z , 2 2 . 5 k h z d e v . w h e n t h e t u n e r i s m o v e d i n 5 0 k h z s t e p s . w i t h a 5 1 k r e s i s t o r b e t w e e n p i n s 3 7 a n d 3 4 . w i t h t h e s d s e n s i t i v i t y a d j u s t e d t o b e 2 0 d b . f 1 = 9 8 . 1 m h z , 4 0 d b f m = 1 k h z , 2 2 . 5 k h z d e v . p i n 2 6 ( s d ) v p i n 2 4 , v s m v p i n 3 3 , v m u t e v v o l t a g e b e t w e e n p i n s 3 7 a n d 3 4 , v a f c v f r e q u e n c y , f r m h z u n i q u e f e a t u r e s o f t h e l a 1 7 8 4 m h a l l d e t e c t i o n c i r c u i t ( 2 ) f i g . 2 8 ? notes on the quadrature input level when a strong field is being received the quadrature signal input (pin 36) requires a 200 mv rms input, and the detection transformer and the damping resistor between pins 36 and 37 must be designed. (we recommend the sumida sa-208 transformer and a 10 k resistor between pins 36 and 37.) when the pin 36 input level falls below 160 mv rms, the hall detection circuit operates and the pin 33 mute drive output voltage increases. therefore, when pin 36 input is from 160 to under 200 mv rms during strong field reception, the muting circuit may or may not operate due to sample-to-sample variations between individual ics. furthermore, the sd function may not operate, and the audio output level may be reduced. incorrect operation due to sample-to-sample variations and temperature characteristics can be prevented by keeping the pin 36 voltage at 200 mvrms or higher. 0 1 2 3 4 5 6 92 94 96 98 100 102 104 106 with pins 34 and 37 shorted. with 5 v applied to pin 24. vmute v qd input level db pin 33 vmute qd input level 36 37 sg 10.7 mhz la1888m 75 75 + 0.022 f fig.29 ?.8 ?.6 ?.4 ?.2 0.2 0.4 0.6 0.8 1 2 3 4 ?00 ?0 ?0 ?0 ?0 0 20 40 60 80 100 120 ?20 with the resistor between pins 36 and 37 open. ? f ? khz ? f=0 ? 10.7 mhz with a 10 k resistor between pins 36 and 37. voltage between pins 37 and 34 (referenced to the pin 37 voltage) thd 1 khz 75 khz dev sa208 + la1787m if input characteristics thd ? % fig.30
no. 6655- 37 /54 la1787m detector output pin 36 ac level mpx out r 36-37 vo qdin open 330 mvrms 235 mvrms 10 k 280 mvrms 200 mvrms ? band muting adjustment procedure the muting bandwidth can be modified as shown in figure 31 with the resistor r bw between pin 34 and 37. 3. am ? am agc system the la1787m rf agc circuit takes its input from three sources: the wide agc pin (pin 46), the middle agc pin (pin 49) and narrow agc. there is also an if agc circuit. 0 40 80 120 160 200 240 280 1.0 2 3 5 7 10 2 3 5 100 7 2 sa208 sumida bandwidth such that the pin 33 voltage 3 2 v ? khz resistor r bw between pins 34 and 37 ? k 37 36 35 34 + + 1 f 0.47 f 10 k r bw ant in 98 mhz 100 db fig.31 r bw ?muting bandwidth + 62 46 57 49 rf 52 31 + 48 44 42 r w 1st mix 10.7mhz cf 2nd mix 450khz cf if amp. det 1st osc x'tal middle agc in narrow agc in wide agc in ant damping rf agc 47 f 3.3 f amp. if agc 2.2 f 240 k v cc v cc a11762 fig. 32
no. 6655- 38 /54 la1787m 800 900 1000 60 80 70 90 100 1100 1200 agc on level frequency ? hz am agc f characteristics wide agc operates for wide band interference wide agc operates for wide band interference middle agc operates for interference within 70 khz of the received frequency. middle agc operates for interference within 70 khz of the received frequency. narrow agc operates at the received frequency. fig.33 70 80 90 100 110 120 2 1.0 3 5 7 10 2 3 5 received frequency: 1 mhz antenna damping on input level db pin 46 input mhz wide band agc circuit 30 0.022 f 0.022 f 0.022 f 46 50 510 50 6db sg antd fig.34 62 57 + v cc 0.022 f 30 620 1mh 100 h 100 h 30mh 15 pf 15 pf 47 f 100 k 0.022 f wide band agc adjustment resistor a12084 fc18 the wide band agc circuit in this ic has the frequency characteristics shown above. the pin 46 input frequency characteristics are identical to those of the rf amplifier gate. this agc circuit serves to prevent distortion at the fet input when a strong signal is applied to the antenna circuit. the level at which the agc circuit turns on can be adjusted to an arbitrary level with the wide band agc adjustment resistor. a delayed agc on level can be handled by reducing the value of the adjustment resistor. fig. 35
? notes on am sd (pin 26) and the sd adjustment pin sd and the if buffer are operated by comparing the s-meter level (v24) and the 5 v reference voltage as shown in figure 36. figure 37 shows the relationship between the am sd, the if count buffer, and the s-meter. no. 6655- 39 /54 la1787m 55 24 23 26 am if + s-meter 100 k 0.47 f 51 k seek 5 v 5 v if buffer if buff amp. sd 0.022 f 100 k 50 pf comparator 50 a v cc a12085 v 23dc v 23ac v 26 v 55 v 24pin larger values of r 55 smaller values of r 55 5 v pin 55: am sd adjustment pin off if buffer on sd on s-meter 0 v a11760 fig. 36 fig. 37
? am high band cut and detector output level adjustment methods the pin 31 am and fm tuner output has an impedance of 10 k in am mode and a few tens of ohms in fm mode. therefore, r31 is used to lower the am detector output level and c31 determines the am high band frequency characteristics. ? am stereo system pins no. 6655- 40 /54 la1787m fig. 39 31 30 + fm detector am detector v cc v cc 10 k noise canceler input 50 k r31 c31 a12086 45 39 v cc v cc ift 50 pf 150 if amp. keyed agc gnd to the am stereo decoder 400 mv rms 450 khz output a11761 fig. 40
no. 6655- 41 /54 la1787m ? am low band cut adjustment method the am low band frequency characteristics can be adjusted with c42, which is inserted between pin 42 and v cc . since the detector is designed with v cc as the reference, c42 must be connected to v cc . am detector 42 + 50 k 50 k 10 k 10 k 10 k c42 v cc to pin 31 a12087 ?0 ?0 ?0 ?0 0 10 3 5 7 0.01 0.001 2 3 5 7 2 3 5 7 2 3 5 7 2 0.1 1.0 10 0.043 f (41pin) % with no used (31pin) 0.022 f (41pin) with no used (31pin) 0.022 f (41pin) 8200 pf (31pin) 0.022 f (41pin) with no used (31pin) fr = 1000 khz fm = 1 khz, 30% detector output ?db frequency ?hz detector output ?frequency fig.42 fig. 41 31 30 + if output noise canceler input 1 k 1 f 2200 pf a12089 h1 w1 2.5ou 2.5ou 19.00 s 981.00 s if audio output f = 10 khz,180 khz dev a12088 fig. 43 fig. 44 4. noise canceler block ? the noise canceler input (pin 30) has an input impedance of about 50 k . check the low band frequency characteristics carefully when determining the value of the coupling capacitor used. note that f c will be about 3 hz when a 1 f capacitor is used in the application. ? pins 8 and 9 are used to set the noise detector sensitivity and the noise agc. it is advisable to first set the noise sensitivity for a medium field (an antenna input of about 50 db ) with pin 8 (the noise sensitivity setting pin), and then set the agc level for a weak field (20 to 30 db ) with pin 9 (the agc adjustment pin). if the noise sensitivity is increased, the agc will become more effective but, inversely, the weak field sensitivity will be reduced. noise canceler 10 khz overmodulation malfunction may be a problem. in particular, when an overmodulated signal is input, the noise canceler may, in rare cases, malfunction. this is due to the fact that the if detector output has a waveform of the type shown in figure 43 due to the bands of the if ceramic filters as shown below. (here, the antenna input is 60 db , the ceramic filters are 150 khz 1 and 180 khz 2, f = 10 khz, 180 khz dev.) the noise canceler reacts to the spikes (whiskers) generated due to this overmodulation, which results in distortion to the audio output. (the spike components due to overmodulation occur due to the bands of the ceramic filters in the tuner.) the following describes a method for resolving this problem. this incorrect operation due to overmodulation is prevented by removing the spike components due to this overmodulation with a low-pass filter consisting of a 1 k resistor and a 2200 pf capacitor shown in figure 44. however, note that the fm separation characteristics in the high band and the am frequency characteristics will change.
no. 6655- 42 /54 la1787m 41 20 k c to the matrix a12090 vo (db) f (hz) 2 p c 20 k 1 a12091 60 50 40 30 20 10 0 10 3 5 7 100 2 3 5 7 1k 2 3 5 7 10k 2 3 v cc = 8.0 v f = 98 mhz 100%mod 80 db in changes in the pin 41 capacitor capacitance (for a 100% high cut ratio) 0.0047 f 0.0022 f 0.001 f 0.01 f 0 f attenuation, hcc db frequency, f hz frequency characteristics fig.47 5. multiplexer block ? hcc (high cut control) frequency characteristics (pin 41) when the hcc function operates, the frequency characteristics of the output signal are determined by the capacitance of the external capacitor connected to pin 41. 1 f c = [hz] 2 c 20 k fig. 45 fig. 46 17 30 12 11 6800 pf 3.9 k 18 0.01 f 50 k pilot cancel gate to the multiplexer noise canceler input a12092 ? pilot canceler adjustment (pins 17 and 18) fig. 48 the pilot canceler signal waveform (pin 19) is a 19 khz signal that contains no third harmonic as shown in figure 48. since this signal has the same phase as the pilot signal, no capacitor is required between pin 18 and ground. since it has no third harmonic component, excellent pilot cancellation can be acquired in both the left and right channels by adjusting with a variable resistor.
19 5 k 0.047 f c to the subdecoder a12093 20 k larger a12094 ? separation adjustment (pin 19) the separation is adjusted by modifying the input level to the subdecoder with the variable resistor connected to pin 19. since only the sub-modulation level is changed by changing the variable resistor setting, the monaural (main) output level is not changed. furthermore, degradation of high band separation in the decoder can be avoided if the impedance of the external capacitor (c) in the subchannel frequency band (23 to 53 khz) is made sufficiently smaller than the variable resistor. no. 6655- 43 /54 la1787m fig. 49 + + 24 s-meter 32 27 fm s-meter mrc 6.4 k 10 k 30 k 3.6 k 75 pf 1 k dc buffer v cc 2 a 100 qmrc c27 v cc to the snc, pin 28 noise amplifier high-pass filter with fc = 70 khz + amplifier an external transistor equivalent to the 2sc536 is required reason: a qmrc level shifter is required to allow a simplified mrc circuit to be used in the la1787m. a11768 6. mrc circuit fig. 50
no. 6655- 44 /54 la1787m + 32 a11769 (1) when there is no ac noise on pin 32 v 24 = v 27 Cv be - q mrc v27 is about 2.5 v when the antenna input is 60 db or higher. (2) since the mrc noise amplifier gain is fixed, the mrc circuit is adjusted by reducing the ac input level. (3) the mrc attack and release are determined by c27 on pin 27. attack: 7 a c27 ? 2 a c27 release: 500 c27 ? 100 notes on the noise canceler the noise canceler characteristics have been improved by implementing the circuit that determines the gate time in logic. since the time constant in earlier noise cancelers was determined by an rc circuit such as that shown in figure 52, the rise time shown in figure 53 was influenced by the values of the resistor and capacitor used. as a result the noise exclusion efficiency was reduced by this delay in the rise time. in the la1787m, this rise time was shortened by implementing the circuit that determines the gate time in logic, allowing it to reliably exclude noise. fig. 51 a11771 a11772 fig. 52 fig. 53
no. 6655- 45 /54 la1787m fm rf mix in 64 pin 1st if in 56 pin 2nd if in 51 pin ant in 11 db 12 db 18 db a11773 fig. 54 gain distribution (fm) this section investigates the gain in each block in the la1787m when the sanyo recommended circuits are used. (test conditions) ambient temperature: 26 c antenna and mixer input frequency: 98.1 mhz first and second if input frequency: 10.7 mhz the input levels when v sm = 2 v will be as follows. ant in: 19 db mix in: 30 db 1st if in: 42 db 2nd if in: 60 db when the gains for each block are determined according to the above, the results are as follows. rf gain: 11 db mix gain: 12 db 1st if gain: 18 db
no. 6655- 46 /54 la1787m (am) this section investigates the gain in each block in the la1787m when the sanyo recommended circuits are used. (test conditions) ambient temperature: 26 c antenna and mixer input frequency: 1 mhz first and second mixer input frequency: 10.7 mhz second if input frequency: 450 khz the gains at each stage will be as follows. rf gain (ant in-pin62): 17 db 1st mix gain (pin62-pin56): 8 db 1st if gain (pin55-pin53): 15 db am rf rf gain 1st mix gain 1st if gain 2nd mix gain 2nd if gain a11774 1st mix 1st if 2nd mix 2nd if am det fig. 55
input circuits for each stage [fm] ? mixer input ? first if input no. 6655- 47 /54 la1787m a11775 a11776 62 50 0.022 f 50 a11778 fr = rf 52 50 0.022 f 50 a11780 fr = 450 khz 45 50 0.022 f 50 ift a11781 fr = 450 khz 49 50 0.022 f 50 a11779 fr = 10.71 mhz (f2nd osc + 0.45 mhz) a11777 63 64 75 0.022 f 75 v in actual measurement 56 75 300 0.022 f 75 fr = 10.7 mhz 51 50 75 300 0.022 f 75 330 0.022 f fr = 10.7 mhz ? if input ? if input ? del input [am] ? first mixer input ? second mixer input
sample am tuner circuit with the lc72144 used together no. 6655- 48 /54 la1787m rf cf cf cf 1st if 2nd mix 450k 300 if a11782 lc72144 xbuff fosc rf cf cf cf 1st mix 10.71 mhz 2nd osc 1st osc if a11783 10.26 mhz 62 10 k af af rf cf cf quadrature detector 10.7 mhz if nc mpx rch lch 59 56 53 49 54 52 31 60 63 64 60 56 53 51 59 am 1st if step fm if 1 f osc 10.25 mhz 10.7 mhz 10 khz, 11 khz 10.7 mhz 2 f osc 10.35 mhz 10.8 mhz 9 khz, 10 khz 10.8 mhz
no. 6655- 49 /54 la1787m 1 2 3 6 4 3 2 4 1 6 s 3 2 4 1 6 s s s 3 2 4 1 6 s [am block] am filteer (sa-1051) am if1 (sa-264) am osc (sa-359) am if2 (sa-1063) 3 2 4 1 6 s 3 2 4 1 6 s am loading (sa-1062) 0.1?uew am rf amplifier (rc875-222j) am ant in (sa-1048) 3 2 4 1 6 s 3 2 4 1 6 s 3 2 4 1 6 s 3 2 4 8 7 1 6 a136 s s c1 c2 [fm block] fm rf (sa-1060) fm osc (sa-1052) fm ant (sa-1061) fm mix (sa-266) 3 2 4 1 6 s s fm det (sa-208) crystal oscillator element kinseki, ltd. frequency: 10.26 mhz cl: 20 pf model no.: hc-49/u-s coil specifications sumida electronics, ltd.
no. 6655- 50 /54 la1787m 1 2 3 6 4 3 2 4 1 6 0.1?uew 3 2 4 1 6 0.05?uew 3 2 4 1 6 0.05?uew [am block] the toko electric corporation am filteer (a2861bis-15327) am if1 (7psgtc-5001a) am osc (v666sns-214by) am if2 (7psgtc-5002y) 3 2 4 1 6 0.05?uew 3 2 4 1 6 s s am loading (269ans-0720z) 0.1?uew am rf amplifier (187ly-222) am ant in (385bns-027z) 3 2 4 1 6 s s ?.1?uew 3 2 4 1 6 s ?.1?uew 3 2 4 1 6 s ?.12?uew 3 2 5 4 1 6 s s ?.07?uew [fm block] fm rf (v666sns-208aq) fm osc (v666sns-205apz) fm ant (v666sns-209bs) fm mix (371dh-1108fyh) 3 2 4 1 6 0.07?muew fm det (dm600deas-8407glf)
no. 6655- 51 /54 la1787m 1 2 3 6 4 3 2 4 1 6 s 5.1 h 3 2 4 1 6 s s 180pf 3 2 4 1 6 s 180pf [am block] sagami elec co., ltd. am filteer (000021055) am if1 (000021057) am osc (000021056) am if2 (000021059) 3 2 4 1 6 s 30mh 3 2 4 1 6 s 100 h am loading (000021061) 2.2mh am rf amplifier (000021063) am ant in (000021062) 3 2 4 1 6 s s 3 2 4 1 6 s 105.5nh 3 2 4 1 6 s 62.7nh 3 2 5 4 1 6 1-2 : 100pf 2-3 : 100pf s s [fm block] fm rf (000021064) fm osc (000021066) fm ant (000021065) fm mix (000021067) 3 2 4 1 6 1-3 : 20 h 3-4 : 120pf s s fm det (010021075) coil specifications
no. 6655- 52 /54 la1787m output, noise, am output, lr output db hcc, snc, rf agc, muting voltage, s-meter voltage, v sm v antenna input db antenna input db total harmonic distortion, thd % antenna input db antenna input db output, noise db output, noise, am output db dcv v mixer output db input db input db mixer input db first if output db first if input db
no. 6655- 53 /54 la1787m ?00 ?0 ?0 ?0 ?0 0 20 ?0 0 20 40 60 80 100 120 140 v cc = 8.5 v f = 1 mhz mod = 1 k 30% noise out ant input, in ?db am i/o characteristics output, noise ?db 0 1.0 2.0 3.0 4.0 5.0 7.0 6.0 20 0 20 40 60 80 100 120 140 v cc = 8.5 v f = 1 mhz rf agc if agc vsm ant input, in db am dc characteristics agc, s-meter voltage v 0 1.0 2.0 3.0 4.0 5.0 7.0 6.0 20 0 20 40 60 80 100 120 140 v cc = 8.5 v f = 1 mhz mod = 1 k 30% 80% fm = 1 khz 80% fm = 1 khz 30% ant input, in db am distortion total harmonic distortion, thd % first if output db frequency, mhz first if output db antenna input db s/n, am output db agc on, separation, input level db frequency, mhz ambient temperature, ta c ambient temperature, ta c separation, sep db ambient temperature, ta c
specifications of any and all sanyo products described or contained herein stipulate the performance, characteristics, and functions of the described products in the independent state, and are not guarantees of the performance, characteristics, and functions of the described products as mounted in the customers products or equipment. to verify symptoms and states that cannot be evaluated in an independent device, the customer should always evaluate and test devices mounted in the customers products or equipment. sanyo electric co., ltd. strives to supply high-quality high-reliability products. however, any and all semiconductor products fail with some probability. it is possible that these probabilistic failures could give rise to accidents or events that could endanger human lives, that could give rise to smoke or fire, or that could cause damage to other property. when designing equipment, adopt safety measures so that these kinds of accidents or events cannot occur. such measures include but are not limited to protective circuits and error prevention circuits for safe design, redundant design, and structural design. in the event that any or all sanyo products (including technical data, services) described or contained herein are controlled under any of applicable local export control laws and regulations, such products must not be exported without obtaining the export license from the authorities concerned in accordance with the above law. no part of this publication may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying and recording, or any information storage or retrieval system, or otherwise, without the prior written permission of sanyo electric co., ltd. any and all information described or contained herein are subject to change without notice due to product/technology improvement, etc. when designing equipment, refer to the delivery specification for the sanyo product that you intend to use. 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. ps no. 6655- 54 /54 la1787m this catalog provides information as of july, 2002. specifications and information herein are subject to change without notice. ?0 ?0 ?0 ?0 0 20 40 60 80 100 120 140 desire mod on ? 40 khz 100 db 80 db 60 db 40 db 100 db 80 db 60 db 40 db desire mod off ant input, in ? db am second-channel interference rejection characteristics output, noise ? db 50 50 50/3 50/3 50/3 30 v in 15pf ant in 65pf jis ant. dummy fu=1040khz fm=400hz 30% f d =1mhz fm=1khz 30% ?0 ?0 ?0 ?0 0 20 40 60 80 100 120 140 desire mod on ? 400khz 100 db 80 db 60 db 40 db 100 db 80 db 60 db 40 db ant input, in ? db output, noise ? db desire mod off 50 50 50/3 50/3 50/3 30 v in 15pf ant in 65pf jis ant. dummy fu = 1400 khz fm = 400 hz 30% f d = 1 mhz fm = 1 khz 30% am second-channel interference rejection characteristics

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