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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, aircraft? 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 LA1780m integrates all six blocks required in a car radio tuner on a single chip. the LA1780m is based on the la1888nm, and features improvements to each of the blocks; improvements designed to provide improved noise characteristics, especially for noise related to multipath, three-signal intermodulation distortion, and two-signal suppression. 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 ?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.) ?since the LA1780m retains the block structure of the la1888nm, products using that ic can be easily converted, allowing further end product miniaturization. package dimensions unit:mm 3159-qfp64e monolithic linear ic ordering number : enn5724a 33100tn (ot)/92498rm (ot) no. 5724-1/38 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 LA1780m 14.0 17.2 1.0 1.0 1.6 0.15 0.35 0.1 15.6 0.8 0.8 3.0max 1 16 17 32 33 48 49 64 2.7 14.0 17.2 1.0 1.0 1.6 0.8 allowable power dissipation, pdmax ?mw ambient temperature, ta ?? mounted on a 40 80 1.3 mm 3 glass epoxy printed circuit board independent ic sanyo: qfp64e (qip64e) [LA1780m]
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 ? 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 51015db 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%. 159db 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%, 61014db 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 220 330 440 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 100 150 200 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?, v cc = 8.0v, in the specified test cricuit for the fm if input continued on next page. no. 5724-2/38 LA1780m specifications maximum ratings at ta = 25? operating conditions at ta = 25? 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? 950 mw operating temperature topr ?0 to +85 ? storage temperature tstg ?0 to +150 ? 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. 80 87 94 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 2 100 106 112 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 260 370 480 mvrms [nc block] nc input (pin 30) gate time t gate1 f = 1 khz, for a 1-?, 100-mv p-o pulse 55 ? noise sensitivity sn the level of a 1 = khz, 1-? 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-? 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 85 120 170 mvrms pin 31 detector output v o -am31 1 mhz, 74 db? f m = 1 khz, 30% modulation, pin 31 75 110 150 mvms agc f.o.m. v agc-fom 1 mhz, 74 db? referenced to the output, the input amplitude 56 61 66 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 3.8 4.8 6.2 v oscillator buffer output v oscbuff am1 no input, the pin 5 output 185 230 mvrms wide band agc sensitivity w-agcsen1 1.4 mhz, the input when v46 = 0.7 v 83 89 95 db w-agcsen2 1.4 mhz, the input when v46 = 0.7 v (seek mode) 74 80 86 db sd sensitivity sd-sen1 am 1 mhz, the ant input level such that the if counter output turns on. 26 32 38 db sd-sen2 am 1 mhz, the ant input level such that the sd pin goes to the on state. 26 32 38 db if buffer output v ifbuff-am 1 mhz, 74 db? unmodulated. the pin 23 output 200 290 mvrms no. 5724-3/38 LA1780m 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.
no. 5724-4/38 LA1780m 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 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 muting attenuation 1 att-1 on b off b on off off on muting attenuation 2 att-2 on b off b on off off on muting attenuation 3 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 signal meter output 1 v sm fm-1 on b off b on off off on signal meter output 2 v sm fm-2 on b off b on off off on signal meter output 3 v sm fm-3 on b off b on off off on signal meter output 4 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 thd-am off off b on on signal meter output 1 v sm am-1 off off b on on signal meter output 2 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 1 w-agcsen 1 off off b on on wide band agc sensitivity 2 w-agcsen 2 off off b on on sd sensitivity 1 sd-sen1 am off off b off off sd sensitivity 2 sd-sen2 am off off b off off if buffer output v ifbuff-am off off b off off test conditions
block diagram no. 5724-5/38 LA1780m if limiter amplifier
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. 5724-6/38 LA1780m
pin no. function description equivalent circuit 3 f.e.gnd pin descriptions no. 5724-7/38 LA1780m 62 pin an antenna damping current flows 1 antenna damping drive when the rf agc voltage (pin 2) reaches v cc -v d . 2 rf agc used to control the fet second gate. oscillator connection 4 osc the transistor and capacitors required for the oscillator circuit are integrated on the chip. 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. 5724-8/38 LA1780m 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. 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 memory circuit connection noise canceller operation. continued from preceding page. continued on next page. differential amp gate circuit
no. 5724-9/38 LA1780m pin no. function description equivalent circuit 15 mpx output (left) deemphasis 16 mpx output (right) 50 ?: 0.015 ? 75 ?: 0.022 ? 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. 5724-10/38 LA1780m pin no. function description equivalent circuit 20 vco the oscillator frequency is 912 hz. kbr-912f108 (kyocera corporation) csb-912jf108 (murata mfg. co., ltd.) composite signal 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. 5724-11/38 LA1780m pin no. function description equivalent circuit forced sd: 2.5 v sd circuit if counter buffer fm s-meter am s-meter outputs a 1-ma current during am reception stereo indicator seek/stop switching 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. fm reception: the voltage v23 switches between three modes as follows. 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 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. 5724-12/38 LA1780m pin no. function description equivalent circuit pin 28 continued from preceding page. continued on next page. the mrc detector time constant 27 mrc control voltage time is determined by a 1-k resistor constant and c2 when discharging and by the 7-? 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. mrc input
no. 5724-13/38 LA1780m pin no. function description equivalent circuit sd circuit fm detector output am detector noise canceller mrc input band muting 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 ?. 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. 5724-14/38 LA1780m pin no. function description equivalent circuit comparator quadrature detector if limiter amplifier band muting comparator s-meter s-meter 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 ?ull voltage 36 qd input when tuned, the voltage between 37 v ref pins 34 and 37, v 34 ?37 , will be 0 v. the band muting function turns on when |v 34 ?37 | 3 0.7 v. v 37 = 4.9 v a 130-? 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. 5724-15/38 LA1780m pin no. function description equivalent circuit 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. 5724-16/38 LA1780m pin no. function description equivalent circuit 45 if output the if amplifier load pin 40 v cc pin 40 v cc continued from preceding page. continued on next page. q1: used for time constant switching during seeks. t = 2.2 ? 300 k seek 44 if agc t = 2.2 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. 5724-17/38 LA1780m pin no. function description equivalent circuit 52 if input the input impedance is 2 k . antenna damping inverter pin 24 for agc use 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. 5724-18/38 LA1780m pin no. function description equivalent circuit pin 40 v cc pin 40 v cc pin 62 v cc 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 ? 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 ?, 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. signal meter
no. 5724-19/38 LA1780m pin no. function description equivalent circuit am/fm switching circuit to rf amp. to 2nd mix continued from preceding page. continued on next page. double balanced mixer pins 60 and 61 are the mixer 10.7-mhz output pins 63 and 64 are the mixer input. 59 mixer output this is an emitter insertion type 60 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 60 and 61. pin 62 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
usage notes 1. notes on v cc and ground 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 4. relationship between pin 23 and pin 26 fm mode pin 26 functions as both the stereo indicator and the sd pin. pin 23: dc-input seek/stop pin (control pin) ac output if counter buffer pin the pin 23 control function and the relationship between pin 23 and pin 26 no. 5724-20/38 LA1780m 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 8fm open am between 0 and a few thousand ohms. if counter buffer sw1 sw2 pin 23 voltage pin 26 pin 26 open open 5 v if counter buffer on sd on open 2.5 v off high-speed sd on under 0.7 v off stereo indicator
no. 5724-21/38 LA1780m used as rds and similar function sd detection by switching this mode. larger r 38 smaller r 38 s-meter v 33 0.7 v or over on and function- ing as sd if counter buffer on v 33 0.7 v or over stereo mono if counter output off notes on fm sd band muting mute drive output s-meter if counter buffer if counter output
am mode pin 55: am sd adjustment pin no. 5724-22/38 LA1780m ? pins that support am stereo to attenuate the pin 39 ac level: add a capacitor between pin 39 and ground. for example, if a capacitor is added between pin 39 and ground, and pin 51 is attached, the am if output will be reduced by about 6 db. s-meter larger r 55 smaller r 35 keyed agc to an am stereo decoder 400-mv rms 450-khz output
notes on the muting attenuation the resistor between pin 58 and ground switches the muting attenuation to one of three levels, ?0, ?0, and ?0 db. this is also related to the tuner? total gain. no. 5724-23/38 LA1780m r mute att open ?0 db 200k ?0 db 30k ?0 db if r33 is reduced, the attenuation will be reduced as listed in the table above. muting time constants attack: 10 k c33 release: 50 k c33 quadrature detector limiter
?mrc circuit if there is no ac noise on pin 32: v27 will be about 2.5 v for an antenna input of 60 db or higher. since the mrc noise amplifier gain is fixed, the mrc circuit is adjusted by reducing the ac input level. the mrc circuit attack and release times are determined by the capacitor c27 on pin 27. attack: 7 ? c27 release: 500 c27 5. fm soft muting by comparing the pin 47 mute on adjustment voltage to the s-meter voltage (v24), the muting on point can be adjusted. no. 5724-24/38 LA1780m s-meter fm s-meter to snc pin 28 noise amplifier fc = the mpf + amp 70 khz required external transistor: 2sc536 or equivalent reason: since the LA1780m mrc is a simplified circuit, an omrc level shifter is required. v24 = v27 ?v be - q mrc smaller r 47 larger r 47 larger r 47 smaller r 47
noise canceller notes the characteristics of the noise canceller have been improved by implementing the circuit that determines the gate time in logic. in earlier noise canceller circuits, since the time constant was determined with an rc circuit such as the one shown in figure 5, the rise time was influenced by the rc circuit time constant as show in figure 6. this meant that the rise was delayed and the associated switching delay resulted in a reduction of the circuit? ability to exclude noise. in the LA1780m, the rise time is made shorter by implementing the circuit that determines the gate time in logic. this allows the LA1780m to eliminate noise reliably. gain distribution (fm) this section analyzes the gain in each of the blocks in the LA1780m when the sanyo recommended circuit is used. test conditions ambient temperature: 26? antenna and mixer input frequency: 98.1 mhz first and second if input frequency: 10.7 mhz input levels when vsm = 2 v were measured to be: antenna input: 19 db mixer input: 30 db first if input: 42 db second if input: 60 db these values allow the gains in each block to be calculated as follows. rf gain: 11 db mixer gain: 12 db no. 5724-25/38 LA1780m figure 5 figure 6
am this section analyzes the gain in each of the blocks in the LA1780 when the sanyo recommended circuit is used. test conditions ambient temperature: 26? antenna and mixer 1 input frequency: 1 mhz mixer 2 input frequency: 10.71 mhz if and detector input frequencies: 450 khz an am dummy is attached. when an input level such that the output becomes ?5 dbm is determined, the i/o characteristics of each stage were determined to be as follows: antenna input: 9.5 db mixer 1 input: 25.6 db mixer 2 input: 29.5 db if input: 36.0 db detector input: 102.0 db these values allow the gains in each block to be calculated as follows. rf gain: 16.1 db mixer 1 gain: 3.9 db mixer 2 gain: 6.5 db if gain: 66.0 db no. 5724-26/38 LA1780m
input circuits used at each stage [fm] mixer input first if input no. 5724-27/38 LA1780m actual measurement if input [am] first mixer input second mixer input if input detector input
3d agc (keyed agc) settings the antenna damping function operates by providing the pin diode antenna damping current from the pin when the pin 2 voltage becomes equal to v cc ?v be . the noise agc circuit operates as follows: when the pin 39 voltage is greater than (6.4/3.6) times the pin 24 voltage, the acg circuit is off. when the pin 39 voltage is less than (6.4/3.6) times the pin 24 voltage, the acg circuit is on. no. 5724-28/38 LA1780m s-meter vs-meter
am agc system the LA1780m rf agc is picked up from three locations. the wide agc determined by rw the middle agc picked up from the pin 49 second mixer input the operating bandwidth is 150 khz to 180 khz (the bandwidth of the 10.7 mhz cf) the narrow agc picked up from pin 52 the operating bandwidth is 7 khz (the bandwidth of the 450 khz cf) no. 5724-29/38 LA1780m am agc frequency characteristics agc on level frequency, ?hz wide agc operates for wide-band interfering stations. wide agc operates for wide-band interfering stations. middle agc operates for interfering stations that are ?0 khz from the received frequency. middle agc operates for interfering stations that are ?0 khz from the received frequency. narrow agc operates at the received frequency.
?sample am application using the lc72144 and the LA1780m no. 5724-30/38 LA1780m am 1st if step fm if 1f osc 10.25 mhz 10.7 mhz 10 k, 1 k 10.7 mhz 2f osc 10.35 mhz 10.8 mhz 9 k, 10 k 10.8 mhz
no. 5724-31/38 LA1780m crystal oscillator element (kinseki, ltd.) hc-49/u-s frequency: 10.26 mhz load capacitance: 20 pf equivalent series resistance: 90 coil specifications (sumida electric co., ltd.) application: am block ?sa-359 (am filter) ?sa-1063 (am if2) ?sa-1048 (am ant in) ?sa-264 (am if1) ?sa-1062 (am loading) ? - 16t - ? 16t 0.08 uew ? - 75t - ? 75t 0.05 uew ? ? 74t 0.07 uew ? - 30t 19t - ? 151t 0.05 uew ? ? 850t 0.05 uew prototype number model number [am block] am filter sa-1051 y-5g (for the first mixer input: 5 mm diagonal) am osc sa-359 s-7lb am if1 (mix) sa-264 pg78 sa-1111 pg57 (5 mm, high reliability) sa-1009 p-5dj (5 mm diagonal) am if2 sa-1063 pg78 sa-1112 pg57 (5 mm, high reliability) sa-265 p-5dj (5 mm diagonal) am loading sa-1062 mg78 am antenna input sa-1048 mg78 am rf amplifier rc875-222j rc875 [fm block] fm rf sa-1060 s-7ldj fm ant sa-1061 s-7ldj fm osc sa-1052 s-7ldj fm mix sa-266 p-7lfj (double balanced mixer) fm det sa-208 qu-7l (quadrature detector) sa-360 qu57 (5 mm diagonal, quadrature detector)
no. 5724-32/38 LA1780m fm block ?sa-1060 (fm rf) ?sa-1052 (fm osc) ?sa-208 (fm det) ?sa-1061 (fm ant) ?sa-266 (fm mix) 1t 0.10 uew ? ? 3t ? ? 3t 0.16 uew ? 2t ? 2t 0.18 uew ? 18 1 t 4 0.08 uew ? ? 70 1 t 4 0.06 uew 3t 3t 0.16 uew ? ? 3t - 6 1 t 2 - 6 1 t 2 0.10 uew coil specifications (toko inc) [am block] toko part no. am ant 269ans-0720 ant 385bns-027z choke 187ly-222k mix lpf a286lbis-15327 am 2nd mix l7tcs-3039a am osc v666sns-213by am ift2 7psg-5002 [fm block] am, fm, mix 3710h-1108fyh fm det dm600deas-8407 fm ant 666sns-219nk fm rf 666sns-218aq fm osc v666sns-205apz
no. 5724-33/38 LA1780m fm block ?3710h-1108fyh (am ?fm ?mix) ?666sns-219nk (fm ant) ?v666sns 205apz (fm osc) ?dm600deas-8407glf (fm det) ?666sns-218aq (fm rf) 2 1 t 2 0.1?zuew ? ? 2 1 t 2 1t 0.1?zuew ? ? 13t ? 6 1 t 2 ? 6 1 t 2 2t 0.07?zuew ? 19 1 t 2 2 1 t 2 ? ? 59t 0.07?zuew ? 2 0.12?zuew am block ?269ans-072z (am ant) ?187ly-222k (choke) ?385bns-027z (ant) ?a286lbis-15327 (mix lpf) ? ? 60t 0.06 3uew 243 0.1?zuew ? ? 60t 0.06?3uew
no. 5724-34/38 LA1780m ?l7tcs-3039a (am 2nd mix) ?7psg-500z (am iftz) ?v666sns-213by (am osc) ? ? 152t ? - 25t - ? 127t 16t 0.05?3uew ? ? 148t ? - 74t - ? 74t 0.05?3uew ? ? 24 1 t 2 ? - 12 1 t 4 - ? 12 1 t 4 0.1?zuew
no. 5724-35/38 LA1780m fm i/o characteristics fm i/o characteristics antenna input, ?db fm distortion antenna input, ?db fm sensitivity suppression antenna input, ?db fm gain distribution (1) antenna input, ?db fm gain distribution (2) input, ?db mixer i/o characteristics input, ?db first if i/o characteristics mixer input, ?db first if input, ?db output, noise, am output, lr output ?db hcc, snc, rf agc, muting voltage, s- meter voltage, v sm ?v total harmonic distortion, thd ?% output, noise ?db output, noise, am output ?db dcv ?v mixer output ?db first if output ?db
no. 5724-36/38 LA1780m first if frequency characteristics. am i/o characteristics frequency, ?mhz am distortion antenna input, ?db am dc characteristics antenna input, ?db fm antenna input temperature characteristics (1) antenna input, ?db fm antenna input temperature characteristics (2) ambient temperature, ta ?? fm antenna input temperature characteristics (3) ambient temperature, ta ?? fm antenna input temperature characteristics (4) ambient temperature, ta ?? ambient temperature, ta ?? first if output ?db output, noise ?db output ?db total harmonic distortion, thd ?% agc, s-meter voltage ?v output - mv rms s/n, am output ?db agc on, separation, input level ?db antenna input ?db separation, sep ?db separation
no. 5724-37/38 LA1780m fm antenna input temperature characteristics (5) fm antenna input temperature characteristics (6) ambient temperature, ta ?? am antenna input temperature characteristics (1) ambient temperature, ta ?? am antenna input temperature characteristics (2) ambient temperature, ta ?? am antenna input temperature characteristics (3) ambient temperature, ta ?? fm soft muting (1) ambient temperature, ta ?? fm soft muting (2) antenna input, ?db fm soft muting (3) antenna input, ?db antenna input, ?db total harmonic distortion, thd ?% s-meter voltage, v sm ?v agc on level ?db agc fom, s/n, qs, sd sensitivity ?db total harmonic distortion, thd ?% s-meter voltage, v sm ?v output ?mv rms output, noise ?db output, noise ?db output ?db output ?db
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 customer? 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 customer? 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 ?elivery 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. 5724-38/38 LA1780m this catalog provides information as of march, 2000. specifications and information herein are subject to change without notice. agc on level ?db with a 10-pf capacitor connected to pin 58 agc on level ?db frequency, ?mhz frequency, ?hz am agc frequency characteristics am agc frequency characteristics

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