DATASHEET SEARCH SITE | · • Level follower type pilot canceller circuit • HCC (high cut control) • Automatic stereo/mono switching • VCO ... VCC1 max Pins 5, 40, and 61

SANYO Electric Co.,Ltd. Semiconductor CompanyTOKYO OFFICE Tokyo Bldg., 1-10, 1 Chome, Ueno, Taito-ku, TOKYO, 110-8534 JAPAN

Ordering number : ENN8085

40706 MS OT B8-7756 No.8085-1/41

OverviewThe LA1776M 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

Feature• Reduced noise in the mixer and amplifier blocks for improved performance• Increased FM front end mixer dynamic range for improved three signal characteristics• Improved AM practical sensitivity and saturated signal-to-noise ratio• S-meter sample-to-sample variations can be improved by using the FM S-meter shift function (Fixed resistors can

be used for the SD, keyed AGC, muting on adjustment, muting attenuation, SNC, and HCC.)• High-speed searching can be implemented using the FM band mute time constant switching function.• Superb listenability provided by improved medium and weak field noise canceller characteristics.• Improved separation temperature dependency characteristics• Excellent FM S-meter voltage linearity• Noise rejection improved by modifications to the NC circuit• Sample-to-sample variation correction circuit (zapping) in the FM IF circuit• Stopping at stations with heavy interference is prevented by increasing the AM wide AGC sensitivity by 10 dB

during seek operations• Built-in anti-birdie filter

SANYO Semiconductors

DATA SHEET

LA1776MMonolithic Linear IC

Single-Chip Tuner IC for Car Radios

Any and all SANYO products described or contained herein do not have specifications that can handleapplications that require extremely high levels of reliability, such as life-support systems, aircraft'scontrol systems, or other applications whose failure can be reasonably expected to result in seriousphysical and/or material damage. Consult with your SANYO representative nearest you before usingany SANYO products described or contained herein in such applications.

SANYO assumes no responsibility for equipment failures that result from using products at values thatexceed, even momentarily, rated values (such as maximum ratings, operating condition ranges, or otherparameters) listed in products specifications of any and all SANYO products described or containedherein.

No.8085-2/41

LA1776M

Recommended Operating Conditions at Ta = 25°C

Parameter Symbol Conditions Ratings Unit

Maximum Recommended supply voltageVCC Pins 5, 9, 40, 46, 54, 59, 60, and 61 8 V

VCCST IND Pin 39 5 V

Operating supply voltage range VCC op 7.5 to 8.5 V

Function List

FM Front End (Equivalent to the Sanyo LA1193)• Double input type double balanced mixer, base injection• 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

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• 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)• Time constant switching during band muting• S-meter shifter

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 function• SNC (stereo noise controller)

SpecificationsMaximum Ratings at Ta = 25°C

Parameter Symbol Conditions Ratings Unit

Maximum supply voltageVCC1 max Pins 5, 40, and 61 9 V

VCC2 max Pins 9, 46, 54, 59, and 60 12 V

Allowable power dissipation Pd max Ta ≤ 85°C 950 mW

Operating temperature Topr –40 to +85 °C

Storage temperature Tstg –40 to +150 °C

No.8085-3/41

LA1776M

• Stereo display pin• Anti-birdie filter

AM• Double balanced mixer• 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 VCC)

No.8085-4/41

LA1776M

Operating Characteristics at Ta = 25°C, VCC= 8.0V, with the specified test circuit and for standards other thanSanyo's for the FM IF input

Continued on next page.

RatingsParameter Symbol Conditions

min typ maxunit

[FM Characteristics] At the FM IF input

Current drain ICCO-AM No input, I9 + I40 + I46 + I54 + I59 + I60 + I61 78 93 112 mA

Demodulation output VO-FM 10.7 MHz, 100dBµ, 1 kHz, 100%mod, The pin 15 output 205 310 415 mVrms

Pin 31 demodulation output VO-31 10.7 MHz, 100dBµ, 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 dBµ, 1 kHz –1 0 +1 dB

Total harmonic distortion THD-FM mono 10.7 MHz, 100 dBµ, 1 kHz, 100% mod, pin 15 0.3 1 %

Signal-to-noise ratio: IF S/N-FM IF 10.7 MHz, 100 dBµ, 1 kHz, 100% mod, pin 15 68 76 dB

AM suppression ratio: IF AMR IF 10.7 MHz, 100 dBµ, 1 kHz, fm = 1 kHz, 30% AM, pin 15 55 68 dB

Att-110.7 MHz, 100 dBµ, 1 kHz. The pin 15

5 10 15 dBattenuation when V33 goes from 0 to 2 V

Muting attenuation Att-210.7 MHz, 100 dBµ, 1 kHz. The pin 15

16 21 26 dBattenuation when V33 goes from 0 to 2 V*1

Att-310.7 MHz, 100 dBµ, 1 kHz. The pin 15

26 31 36 dBattenuation when V33 goes from 0 to 2 V*2

Separation Separation10.7 MHz, 100 dBµ, L+R = 90%, pilot = 10%. The pin 15 output

30 40 dBratio

Stereo on level ST-ON The pilot modulation such that V39< 0.5 V 2.3 3.5 5.5 %

Stereo off level ST-OFF The pilot modulation such that V39> 3.5 V 0.6 1.6 %

Main total harmonic distortion THD-Main L 10.7 MHz, 100 dBµ, L+R = 90%, pilot = 10%. The pin 15 signal 0.3 1.2 %

Pilot cancellation PCAN 10.7 MHz, 100 dBµ, pilot = 10%. 20 30 dB

The pin 15 signal/the pilot level leakage. DIN audio

SNC output attenuation AttSNC10.7 MHz, 100 dBµ, L-R = 90%, pilot = 10%.

4 8 12 dBV28 = 3 V → 0.6 V, pin 15

AttHCC-1 10.7 MHz, 100 dBµ, 10 kHz, L+R = 90%, pilot = 10%.2 6 10 dB

HCC output attenuationV29 = 3 V → 0.6 V, pin 15

AttHCC-2 10.7 MHz, 100 dBµ, 10 kHz, L+R = 90%, 7 11 15 dB

pilot = 10%. V29 = 3 V → 0.1 V, pin 15

Input limiting voltage Vi-lim 100 dBµ, 10.7 MHz, 30% modulation. The IF input such35 42 49 dBµ

that the input reference output goes down by 3 dB

Muting sensitivity Vi-mute The IF input level (unmodulated) when V33 = 2 V 45 53 61 dBµ

SD-sen1 FM The IF input level (unmodulated) (over 100 mV rms) 72 80 88 dBµ

SD sensitivity such that the IF counter buffer output goes on

SD-sen2 FM Unmodulated IF input such that the SD pin goes to the on state 72 80 80 dBµ

IF counter buffer output VIFBUFF-FM 10.7 MHz, 100 dBµ, unmodulated. The pin 23 output 150 230 300 mVrms

VSM FM-1 No input. The pin 24 DC output, unmodulated 0.1 0.3 V

Signal meter outputVSM FM-2 60 dBµ. The pin 24 DC output, unmodulated 0.6 1.2 1.8 V

VSM FM-3 80 dBµ. The pin 24 DC output, unmodulated 2.0 2.7 3.5 V

VSM FM-4 110 dBµ. The pin 24 DC output, unmodulated 4.5 5.2 5.9 V

Muting bandwidth BW-mute 100 dBµ. The bandwidth when V33 = 2 V, unmodulated 150 220 290 kHz

Mute drive output VMUTE-0 No input. The pin 33 DC output, unmodulated 1.8 2.5 3.3 V

VMUTE-100 100 dBµ, 0 dBµ. The pin 33 DC output, unmodulated 0 0.1 0.2 V

[FM FE Mixer Input

N-AGC on input VN-AGC83 MHz, unmodulated.

83 90 97 dBµThe input such that the pin 2 voltage is 2.0 V or below

W-AGC on input VWAGC83 MHz, unmodulated. The input such that the pin 2

98 104 110 dBµvoltage is 2.0 V or below. (When the keyed AGC is set to 4.0 V.)

Conversion gain A.V 83 MHz, 80 dBµ, unmodulated. The FE CF output 90 140 220 mVrms

Oscillator buffer output VOSCBUFFFM No input 85 110 165 mVrms

[Multipath Rejection Circuit] MRC input (pin 27)

MRC output VMRC V24 = 5 V 2.9 3.0 3.1 V

MRC operating level MRC-ONThe pin 26 input level at f = 70 kHz such that

35 55 70 mVrmspin 24 goes to 5 V and pin 27 goes to 2 V

No.8085-5/41

LA1776M

RatingsParameter Symbol Conditions

min typ maxunit

[AM Characteristics] AM ANT input

Practical sensitivity S/N-30 1 MHz, 30 dBµ, fm = 1 kHz, 30% modulation, pin 15 20 dB

Detector output VO-AM 1 MHz, 74 dBµ, fm = 1 kHz, 30% modulation, pin 15 140 210 280 mVrms

Pin 31 detector output VO-AM31 1 MHz, 74 dBµ, fm = 1 kHz, 30% modulation, pin 31 130 190 260 mVms

AGC F.O.M. VAGC-FOM1 MHz, 74 dBµ, referenced to the output, the input amplitude

51 56 61 dBsuch that the output falls by 10 dB. Pin 15

Signal-to-noise ratio S/N-AM 1 MHz, 74 dBµ, fm = 1 kHz, 30% modulation 50 56 dB

Total harmonic distortion THD-AM 1 MHz, 74 dBµ, fm = 1 kHz, 80% modulation 0.3 1 %

Signal meter outputVSM AM-1 No input 0.0 0.1 0.5 V

VSM AM-2 1 MHz, 130 dBµ, unmodulated 3.9 4.9 6.8 V

Oscillator buffer output VOSCBUFF AM No input, the pin 15 output 185 230 mVrms

Wide band AGC sensitivityW-AGCsen1 1.4 MHz, the input when V48 = 0.7 V 89 95 101 dBµ

W-AGCsen2 1.4 MHz, the input when V48 = 0.7 V (seek mode) 80 86 92 dBµ

SD sensitivitySD-sen1 AM 1 MHz, the ANT input level such that the IF counter output turns on. 24 30 36 dBµ

SD-sen2 AM 1 MHz, the ANT input level such that the SD pin goes to the on state. 24 30 36 dBµ

IF buffer output VIFBUFF-AM 1 MHz, 74 dBµ, unmodulated. The pin 23 output 180 220 mVrms

Note: These measurements must be made using the either the IC-51-0644-692 IC socket (manufactured by Yamaichi Electronics).* 1. When the resistor between pin 58 and ground is 200 kΩ.* 2. When the resistor between pin 58 and ground is 30 kΩ.

Package Dimensions

Unit:mm

3159A

Continued from preceding page.

Mounted on a 40 × 18 × 1.3 mm3

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No.8085-6/41

LA1776M

LA1776M AC Test Circuit

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No.8085-7/41

LA1776M

LA1776M Application Circuit Example

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An antenna damping current flows when the RFAGC voltage (pin 1) reaches VCC – VD.

FM antenna dampingdrive pin

No.8085-8/41

LA1776M


Pin Descriptions

1

ANT

1000 pF

1000 pF

100 Ω500 Ω

VCC 62 pin

RFAGC

1

2

2

NAGCDET

WAGCDET

KEYEDAGC

ANTDAMPING

VCC (61pin)

VCC-VD

12 kΩFET2ND GATE

+

Used to control the FET second gate voltage.

In AM mode, forcibly set the pin 2 voltage to the lowlevel and apply AGC to the FM RF system.

RF AGC

3

Oscillator connection

This pin is designed to drive an external oscillatorcircuit that uses external transistors and capacitors.

FM OSC

4

VCC VCC (5 pin)

25 pF

20 pF2 kΩ

10 kΩ

VT

4

EF. GND

Pin No. Pin Description Equivalent circuit

No.8085-9/41

LA1776M



3

5

FM OSC

AM/FMswitching circuit

VCC

4V

GND

8V

+–+

5 AM/FM SW

The pin 5 input voltage state (high or low) switchesbetween AM and FM modes.

V5 = high (8 V): FM

V5 = low (0 V): AM

This level is also used as the FM oscillator circuitVCC.

6 7

3 kΩ

15 kΩ

1 kΩ

3 kΩ

3 kΩ

2 MΩ0.01 µF

0.022 µF

200 Ω

+

67

Noise AGC sensitivityAGC adjustment

After setting up the medium field (about 50 dBµ)sensitivity with the noise sensitivity setting pin (pin6), set the weak field (about 20 to 30 dBµ) sensitivitywith the AGC adjustment pin (pin 7)

8

FM OSC AM OSC

8AM/FM oscillator bufferoutput

This pin is shared by the AM and FM systems.

9

VCC (16 pin)

A L C

9 AM OSC

AM system first oscillator

This oscillator can provide frequencies for use up tothe shortwave band.

This pin includes an ALC circuit.



No.8085-10/41

LA1776M



12 11 10VCC

0.01µF 6800 pF

Gate circuit

LPF

Differentialamp

1011

Memory circuitconnection

Recording circuit used during noise cancelleroperation.

11 12

30 kΩ

VCC

PLL

N.C

0.01 µF

12 Pilot input Pin 12 is the PLL circuit input pin.

13

10 kΩ

5.6 V 20 pF

33 pF

X tal10.26 MHz

to 2ndMIX

13 AM 2nd OSC

Crystal oscillator circuit

Use the HC-49/U-S manufactured by Kinseki, Ltd.

CL = 20 pF

14 N. C, MPX, MRC, GND Ground for the N, C, MPX, and MRC circuits


No.8085-11/41

LA1776M



15

3.3 kΩ3.3 kΩ

VCC

0.015 µF 0.015 µ F

16

1516

MPX output (left) MPX output (right)

AM output

FM multiplex output

For deemphasis, use the following capacitors:

50 µS: 0.015 µF

75 µS: 0.022 µF

17 18

VCC

50 kΩ

10 kΩ

0.01 µF 50 kΩ

6.7 kΩ17

Pilot canceller signalinput

Adjustment is required since the pilot signal levelvaries with the sample-to-sample variations in the IFoutput level and other parameters.

17 18

VCC

0.01 µF

330 Ω300 Ω

50 kΩ

18Pilot canceller signaloutput

Pin 18 is the output pin for the pilot canceller signal.

No.8085-12/41

LA1776M



19

10 kΩDECODER

20 kΩ

0.01 µF

Compositesignal

19Separation adjustmentpin

Use a trimmer to adjust the subdecoder input level.(The output level is not modified in mono and mainmodes.)

20

CSB912JF108

VREF

20 VCOThe oscillator frequency is 912 Hz.

JF108

21 22

6 kΩ

6 kΩ

19 kHz∠90º

VREF

+

+

+

2122

PHASE COMP



No.8085-13/41

LA1776M



23

3.3 V

1.3 V

3.3 V

51 kΩ

STOP 2.5 V/5V

AM SD

FM SD

FM SD+–

+–

+–

23IF counter bufferseek/stop switching

This pin functions both as the IF counter buffer (ACoutput) and as the seek/stop switch pin.

FM mode

5 V (high): Seek mode

2.5 V: High-speed SD mode

0 V (low): Reception mode

AM mode

5 V (high): Seek mode

0 V (low): Reception mode

32

24

10 kΩ

10 kΩ

VCC

FMS-meter

AMS-meter

AM/FMSW

24

32

AM/FM signal meter

Dedicated FM signalmeter

Fixed-current drive signal meter output

27

7 µA

100 Ω

C2

VCCVCC

28 pin

+

27 MRC outputThe MRC detector time constant is determined by a100 Ω resistor and C2 when discharging and by the7-µA current and C2 when charging.

30 kΩ

C1

Dedicated MRC S-meter voltage

R226 +

–26 MRC AC input

The LA1776M supports two methods: detecting IF S-meter wideband components and detecting thenoise canceller high-pass filter noise output.

The noise amplifier gain is determined by R2 and theinternal 30 kΩ resistor as shown in the figure. Notethat the frequency characteristics are determined byC1.

No.8085-14/41

LA1776M



28

VCC

28 SNC control input The sub-output is controlled by a 0 to 1-V input.

32 29

VCC

1 µF1000 pF+

29 HCC control inputThe high-frequency output is controlled by an inputin the 0 to 1 V range.

VCC

50 kΩ

4.2 V

31 30

0.22 µF+

30 Noise canceller input The input impedance is about 50 kΩ.



No.8085-15/41

LA1776M



31

30

FMdetectoroutput

AMdetectoroutput

VCC

VCC

10 kΩ R

0.22 µF

Noisecanceller

50 kΩ

+30

31

Noise canceller input

AM/FM detector output

Pin 30 is the noise canceller input. The inputimpedance is 50 kΩ

Pin 31 is the AM and FM detector output

In FM mode, this is a low-impedance output.

In AM mode, the output impedance is 10 kΩ.

The AM detection output can be modified byadjusting the value of R.

32

29

VCC

VSM

10 kΩ 1000 pF32 IF S-meter output FM S-meter output block

33

SOFTMUTE

Bandmuting

SEEKOFF

VCC

0.022 µF

C1

10 kΩ 50 kΩ

MUTEAMP.

SD circuit

33 Mute drive output

• The muting time constant is determined by anexternal RC circuit as described below.Attack time: TA = 10 kΩ × C1Release time: TR = 50 kΩ × C1

• Noise convergence adjustmentThe noise convergence when V33 is 2 V will beabout 40 dB.(The basis can be varied from 5 to 35 dB for a 1kHz 22.5 kHz deviation output.)

* : There is no hole detection function.

• Muting off functionThe muting function is turned off by a 4 kΩ resistorbetween pin 33 and ground.

No.8085-16/41

LA1776M



37 36 35 34

Quadraturedetector

VCC

R2

VCC

VCC VCC

VCC

IF limitter amplifier

343536

Vref: 2.7 V

QD output

Null voltage

When tuned, the voltage between pins 34 and 37,V34 – 37, will be 0 V.

The band muting function turns on when |V34 – 37| ≥0.7 V.

38 37 34

Bandmuting

C38

500 Ω

R1

C34

During FMreception: on

+

38Band muting timeconstant switching

R1: Resistor that determines the width of the bandmuting function

When R1 is larger ... The band becomes narrower

When R1 is smaller ... The band becomes wider

The band muting time constants are determined bythe following components.

During reception: R1, C34, and C38

During seek: R1 and C34

The band muting time constant can be made smallerby reducing the value of C34. Degradation of totalharmonic distortion characteristics at lowtemperatures can be prevented by make C38 larger.

39

5 V

19

AM/FMSD

Stereoindicator

Seek/stopswitching

39AM/FM SD pin

Stereo indicator

V23 is switched by the voltage mode as describedbelow.

FM mode

5 V: V23 operates in conjunction with the SD pin and IF counter buffer.2.5 V: V23 operates as the forcible SD mode pin.0 V: Reception mode

AM mode (There are two modes: 0 V or 5 V.)

5 V: Linked operation with the seek SD pin.2.5 V: Reception mode, no function.0 V: Reception mode


No.8085-17/41

LA1776M



40 VCC IF, NC, MPX, VCC

42

DET

VCC

VCC

3.3 kΩ

3.3 kΩ

30 kΩ

30 kΩ

30 kΩ

19 kHz∠0º

BIAS

1 µF

1 kΩ

C

1kΩ

+–

+

+

42Pilot detector

AM L.C

This pin us used for both FM pilot detection and AMlow-cut filter.

Pilot detection

The system is forced to mono mode when a 1 MΩresistor is inserted between pin 42 and ground. InAM mode, the frequency characteristics of theunneeded audio band below 100 Hz are modifiedproducing a clear audio signal.

AM low-cut filter

The cutoff frequency fC can be determined from thefollowing formula.

FC = 1/2 π× 3.3 kΩ × C

0.8 V

Vsm

N-AGC 431 kΩ

1 kΩ

+–

43 Keyed AGC

Dedicated keyed AGC S-meter

The keyed AGC function starts operation when V43becomes less than or equal to 0.8 V. (Narrow AGCoff mode.)

24

38

SD

R

SD Adj

Vsm

4 V

Comparator

S-meter

20 kΩ

+–

41 FM SD

The comparison voltage is controlled by an externalresistor.

In seek mode, the seek operation will stop when V41< Vsm.



No.8085-18/41

LA1776M



44

soft mute

100 kΩ

MUTE

2.7 V30 kΩ

44FM muting on leveladjust

Modify the value of the external resistor to adjust themuting on level.

48

DET

45

VCC

VCC

3.3 µFC

3.3 kΩ

3.3 kΩ

300 kΩ

TR1

10 Ω

500 Ω

SEEKON

IFAGC

+

45 IF AGC

TR1: Seek mode time constant switching diode

Discharge diode

• Reception

τ = 3.3 µF × 300 kΩ

• Seek

τ = 3.3 µF × 10 Ω

The external capacitors are connected to VCC.

This is because the IF amplifier operates referencedto VCC.

46

DET

40 pin VCC

40 pin VCC

46 IF output The IF amplifier load


No.8085-19/41

LA1776M



47

56

Antennadamping

VCC

5.8 V 10 kΩ

3.3 µF

47 µF

For AGC use

–++

+

4756

RF AGC bypass

RF AGC

RF AGC rectification capacitor

The low frequency distortion is determined asfollows:

Increasing C47 and C56 improves the distortion but makes the response slower.

Reducing C47 and C56 aggravates the distortionbut makes the response faster.

* :If the audio is disturbed due to the RF AGC whenthere are rapid changes in the reception fieldstrength (on the order of off to 80 dBµ), thecombination of the time constants due to C56 andC47 must be changed.

50

51

5.7 V

10 kΩ 10 kΩ

0.022 µF

330 Ω5051

FM IF input

IF bypass

Due to the high gain of the limiter amplifer, caremust be taken when choosing the grounding pointfor the limiter amplifer input capacitor to preventoscillation.

52

2 kΩ

100 Ω

52 IF input The input impedance is 2 kΩ.

53

57

IF OUT

IF IN

3.75 V

200 Ω

300 Ω

61 pin VCC

53

57

IF amplifier output(AM/FM)

IF amplifier input(AM/FM)

• First IF amplifier input pin

• Inverted output amplifierThe gain is switched between AM and FM modes

No.8085-20/41

LA1776M



54

49

OSC

VCC 40 pin

40 pin VCC

10 kΩ10.7 M 10.7 M

5449

AM MIX OUT

AM MIX IN

The mixer coil connected to the pin 54 mixer outputmust be wired to VCC (pin 40).

The pin 49 mixer input impedance is 10 Ω

55

58

W-AGC

20 kΩ

1.5 kΩ

N-AGC62 pin

VCC

30 pF

50 pF

S-meter

AM SD

C1

C2

MIXIN

MIXOUT

+–

58

W-AGC IN

AM-SD Adj

N-AGC IN

Pins 55 and 58 include built-in DC cut capacitors.

The AGC on level is determined by the values of thecapacitors C1 and C2.

Pin 55 functions as the SD sensitivity adjustment pinin AM mode.

V55 is changed by the value of the external resistor.

SD is operated by comparing V55 with the S-metervoltage.

Seek mode stop condition: V55 < Vsm

48

VCC

VCC

50 pF

100 Ω

20 kΩ

ANT DAMPINGDRIVER

W.AGC AMP.

FM Vsm

I48

0.022 µF48

AM antenna dampingdrive output

Wideband AGC input

FM S-meter voltage shift

I48 = 6 mA

Antenna damping current

Resistor values under 5 kΩ cannot be used for theFM S-meter shift resistor.


No.8085-21/41

LA1776M


59

60

62

OSC

10 kΩ596062

FM/AM MIX output

AM MIX input

Y-type mixer circuit

Pins 59 and 60 are the mixer outputs

10.7 MHz (10.71 MHz)

Input impedance: 10 kΩ

V62 = 2.3 V

59

60

63

O S C

64

1ST.IF

30 Ω

VCC

10 pF

10 pF

RF AMP

59606364

Mixer output

Mixer input

Double balanced mixer

Pins 59 and 60 are the mixer 10.7-MHz output

Pins 63 and 64 are the mixer inputs

These are base injection type inputs.

Note: The lines for pins 63 and 64 must be keptseparated from the lines for pins 59 and 60.


No.8085-22/41

LA1776M

Test Conditions

Parameter Symbol SW1 SW2 SW3 SW4 SW5 SW6 SW7 SW8 SW9 SW10

Current drain ICCO-AM OFF B OFF B — ON OFF OFF ON —

Demodulation output VO-FM ON B OFF B — ON OFF OFF ON —

Pin 31 demodulation output VO-31 ON B OFF B — ON OFF OFF ON —

Channel balance CB ON B OFF B — ON OFF OFF ON —

Total harmonic distortion (FM) THD-FM mono 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 ON OFF ON —

Att-3 ON B OFF B — ON OFF ON 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 VIN-LIM ON B OFF B — ON OFF OFF ON ON

Muting sensitivity VIN-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 VIFBUFF-FM ON B OFF B OFF OFF OFF OFF ON —

VSM FM-1 ON B OFF B — ON OFF OFF ON —

Signal meter output (FM)VSM FM-2 ON B OFF B — ON OFF OFF ON —



Muting Bandwidth BW-mute ON B OFF B — ON OFF OFF ON —

Mute drive outputVMUTE-0 ON B OFF B — ON OFF OFF ON —

VMUTE-100 ON B OFF B — ON OFF OFF ON —

N-AGC on input VNAGC ON A ON B — ON OFF OFF — —

W-AGC on input VWAGC ON A ON B — ON OFF OFF — —

Conversion gain A.V ON A ON B — ON OFF OFF — —

Oscillator buffer output VOSCBUFF-FM ON A ON B — ON OFF OFF — —

MRC output VMRC 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 VO-AM OFF — OFF B ON ON — — — —

Pin 31 detection output VO-AM31 OFF — OFF B ON ON — — — —

AGC F.O.M. VAGC-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)VSM AM-1 OFF — OFF B ON ON — — — —

VSM AM-2 OFF — OFF B ON ON — — — —

Oscillator buffer output VOSCBUFF-AM OFF — OFF B ON ON — — — —

Wide band AGC sensitivityW-AGCsen 1 OFF — OFF B ON ON — — — —

W-AGCsen 2 OFF — OFF B ON ON — — — —

SD sensitivitySD-sen1 AM OFF — OFF B OFF OFF — — — —

SD-sen2 AM OFF — OFF B OFF OFF — — — —

IF buffer output VIFBUFF-AM OFF — OFF B OFF OFF — — — —

No.8085-23/41

LA1776M

Usage Notes

1.AM/FM SwitchingPin 5 is used for switching between AM and FM (dedicated FM oscillator VCC)

FM mode: When the pin 5 voltage is greater than 4 V.AM mode: When the pin 5 voltage is less than 4 V.

2.Pin 39: AM/FM SD and Stereo IndicatorPin 39 is used both for AM and FM station detection and as a stereo indicator.

FM mode5 V: Operates as the SD pin, coupled to the IF counter buffer.2.5 V: Operates in forced SD mode.0 V: Reception mode

AM mode (two modes: 0 V and 5 V)5 V: Operates coupled as the seek SD pin2.5 V: Reception mode, no function0 V: Reception mode

3.Front EndNotes on interface characteristicsLike the previous Sanyo products, the LA1776M includes the 3 D (triple dimension) AGC circuit. This circuitallow the LA1776M to achieve at the same time both good three-signal interference characteristics (intermodulationcharacteristics) and two-signal sensitivity suppression characteristics.

3-1.Intermodulation characteristicsThe LA1776M prevents intermodulation from occurring by applying dual high-band AGC.

V5 VCC

43 5

FM OSC

FM/AM SW

AM/FM SW

FE

GN

D

FM

OS

C

FM

8V

/

50

60

70

80

90

100

110

-5 -4 -3 -2 -1 0 1 2 3 4 5

AG

C o

n se

nsiti

vity

Keyed AGC (10 K)

Narrow AGC (47 p)

∆ f [MHz]

Center frequency: 98.1 MHzKeyed AGC (43 pin) = 10 K

Wide AGC (47 p)

No.8085-24/41

LA1776M

3-2.Two-Signal Sensitivity SuppressionLike the earlier Sanyo products, the LA1776M's 3D AGC determines the amount of wide-band AGC appliedusing the information acquired from three frequency characteristics.

RF and antenna circuit information: Mixer input AGCMixer circuit information: Mixer output AGC <- Three dimensionsCF selectivity: S-meter output

3-3.FE Block AGCLike the earlier Sanyo products, the LA1776M uses the follow two functions(1) PIN diode antenna input control(2) FET second gate controlThe AGC input pins are pin 58 (narrow AGC) and pin 55 (wide AGC).

Applying AGCThe PIN diode drive circuit is turned on when (roughly) (VCC – V2) is 1 V or higher.In application circuits, there will be about 30 to 40 dB of attenuation. When an adequate current flows in theantenna attenuator PIN diode and the impedance falls, the FET second gate voltage falls, the FET gm falls, andthe AGC operates. The recommended FET is the Sanyo 3SK263, which is an enhanced type MOSFET, andthus the full AGC will be applied when the voltage between the second gate and the source (G2-S) is 0. Notethat if a depletion type MOSFET were used, AGC would not be applied unless VG2-Swere lower than 0 V.

3-4. MixerThe LA1776M's mixer circuit is a double balanced mixer that used balanced signals for both the input andoutput.

Input type: base inputInput impedance: 2 kΩ

7

6

5

4

3

2

1

0

9

8

–20 –10 0 20 3010 40 50 60 70 80 90 100 110 120 130

Pin 2 voltage

Region where the AGCdoes not operate

AGC amount dueto the PIN diode

PIN diode voltage

AGC amount dueto the MOSFET'ssecond gate.

AG

C v

olta

ge –

V

Field strength - dBµ

OSC

63 64

59 60

2 kΩ

2 kΩ

No.8085-25/41

LA1776M

3-5.MixerPin 4: The FM oscillator circuit is formed from external components.Pin 8: AM/FM oscillator buffer

3-6.FM: First IF Amplifier (10.7 MHz)Input impedance: 330 Ω (pin 57)Output impedance: 330 Ω (pin 53)

VCC VCC

VT

VCC

AM OSCBUFF

8

4

FM/AM OSC BUFF

No.8085-26/41

LA1776M

4. FM IF4-1.Notes on FM SD and SD Adjustment

The FM station detection and IF counter buffer operate with the following elements.

The following conditions must be met for the station detection and IF counter buffer to operate.(1) V24 > V41 - The S-meter voltage must be higher than the pin 41 voltage(2) V33 < 0.7 V (Vbe) - The band muting function must not be operating.(3) V23 = high - A high level (VDD) must be applied to pin 23 from a 51 kΩ resistor.

The figure below shows the relationships between the FM station detection, the IF counter buffer output, the S-meter voltage, and the muting operation output.

FM S-meter

SD

4 V 2.7 V

FM SD adjmute on

Soft mute

mute AMP

mute ATT

IF conut

IF conut

IF conut

FM IF

ST IND

SD/ST

2

12 12

13

13

mute d

SEEK = OF

SEEK = OFF

AFC

1 2

AFC

2.7 + 0.6 V-0.6 V

20 kΩ 30 kΩ

200 kΩ 30 kΩ

23

2.5 V 5 V

5 V

583344

38 37

3941

VCC

VCC

+_

+_

+_

+_

+_

V23DC

V23AC

V26

V33

V38

V24

5 V

Largervaluesof R33

Smaller values of R33

S-meter

V33over 0.7 V

V33over 0.7 V

SD as anSD signal

SDON

SDON Stereo

Mono

OFF OFFIF

countbuffer

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.

No.8085-27/41

LA1776M

4-2.Transient Response Characteristics During Automatic SelectionThe transient response characteristics when the SD or IF counter buffer are turned on or off are determined bythe time constant at the pins shown below.(1) AFC time constant – Pin 37(2) Muting time constant – Pin 33(3) S-meter time constant – Pin 24

(1) Station detection time constant due to the pin 37 AFC voltagetime constantSince there is a function for switching the AFC time constant, itis possible to set the time constants so that there are no harmfuleffects. For reception mode, if the pin 38 capacitor value is notmade comparatively large, the total harmonic distortion may bemade worse.

• Reception mode time constant: Make the time constant longerwith R34_37, C37, and C38.

• Seek mode time constant: A high-speed response can beachieved with R34_37 and C37, since the seek mode timeconstant is independent of C38.

• The following values are recommended.C37: About 0.022 µFC38: About 1 µF

(2) Station detection time constant due to the pin 33 muting voltage time constantThe volume changes due to fluctuations in the field during weak field reception can be made smoother bysetting the soft muting operation attack and release times appropriately.

(3) Station detection time constant due to S-meter time constantSince the pin 24 current (I24) changes with the field strength, the time constant also changes. There is nohysteresis in the comparator circuit. Note that if a smaller value is used for C24, the MRF frequencycharacteristics setting will need to be changed as well.

C37

C38

AFC

FM STOP: ONFM SEEK: OFF

C34

Vref

R34-37

1 kΩ

3734 38

VCC

+–

++

MUTEAMP

MUTEDRIVE

10 kΩ 50 kΩ

C33

33

Attack Release

24

10 kΩ

FM S-meter AM S-meter

4-3.FM Muting Function Control (pin 44: soft muting) and Attenuation Setting (pin 58)The -3 dB limiting sensitivity can be adjusted by changing the value of R44.The muting attenuation can be switched between three levels (-10, -20, and -30 dB) with R58.

5.AM BlockThe LA1776M adopts an upconversion method.

5-1.AM AGC SystemThe RF AGC pickup operates according to the input level on pins 48 and 49.Pin 48: AGC based on the components in the 10.7 MHz CF band.Pin 49: Wideband AGC (The level at which the wideband AGC turns on can be adjusted with Rw.)(The seek mode wideband AGC on level is increased by 10 dB.)

No.8085-28/41

LA1776M

Output level

When R44 is largeWhen R44 is small

V33

Output level

R58:OPENR58:200K

R58:30K

R58 Mute ATT

OPEN –10 dB

200 K –20 dB

30 K –30 dB

The RF AGC is picked up from two places.1. The wideband AGC determined by RW.2. Midband AGC picked up from the second mixer at pin 49.Operating bandwidth: 150 to 180 kHz (the 10.7 MHz CFbandwidth)

62

49

56

57 57RF 52 31

47

45

42

RW

1st MIX10.7 MHz CF

4910.7 MHz

2nd MIX450 kHz CF

IF Amp.IF Amp.

DET

AM AGC SYSTEM

1st OSC X'tal

Middle AGC IN

Wide AGC IN

ANTDUMPING

RF AGC

22 µF 3.3 µF

1 µF

IF AGC

1 µF

VCC

VCC

+ +

+

+

No.8085-29/41

LA1776M

5-2.AM SD Pin (pin 39) and the AM SD Adjustment PinThe LA1776M compares V24 and the reference voltage V55 to operate SD and the IF counter.

5-3.AM Wideband Cut and Detection Output Adjustment MethodsThe AM/FM detection output (pin 31) has an output impedance of 10 kΩ in AM mode, and an impedance of afew tens of ohms in FM mode. Therefore the AM detection output level is lowered by R31 and the AMwideband frequency characteristics are determined by C31.

55 24 23 39

AM IFS-meter

100 kΩ0.47 µF

51 kΩ

SEEK

5 V

5 V

IF BUFER

IF Buff Amp.

SD

0.022 µF

100 kΩ

50 pF

Comparator

50 µA

VCC+–

V23DC

V23AC

V39

V55

V24PIN

Largervaluesof R55

Smaller values of R55

5VPin 55: AM SD adjustment pin

OFF IF Buffer ON

SD ON

S-meter

0 V

31

30

FMdetector

AMdetector

VCC

VCC

10 kΩ

Noise cancellerinput 50 kΩ

R31 C31

+

No.8085-30/41

LA1776M

5-4.AM Low Region Cut AdjustmentThe AM low frequency region frequency characteristics can be adjusted with capacitor C42, which is insertedbetween pin 42 and ground. Since this capacitor is shared with the FM pilot detector, it is connected to ground.To prevent incorrect operation of the pilot detector, C42 must have a value of 0.33 µF or higher.

6.Noise Canceller Block6-1.The noise canceller input (pin 30) has an input impedance of about 50 kΩ. The low band frequency

characteristics require care when determining the value for the coupling capacitor. Note that fC will be about 3Hz in an application that uses a 1 µF capacitor.

6-2. The noise detection sensitivity and the noise AGC are set with pins 8 and 9. Good settings can be acquired byfirst setting the medium field strength (corresponding to an antenna input of about 50 dBµ) sensitivity with thenoise sensitivity setting pin (pin 8) and then setting the weak field (20 to 30 dBµ) with the AGC adjustment pin(pin 9). Note that if the noise detection sensitivity is increased, the effect of the AGC will be improved, but thatinversely the weak field sensitivity will be decreased.

The problem of incorrect operation of the noise canceller for 10 kHz overmodulation occurs when anovermodulated signal is input and the noise canceller responds to that signal even though it should not. Thecause of this is the IF detector output taking on the sort of waveform shown in the figure due to the band of theIF ceramic filter as shown below. (150 kHz × 1, 180 kHz (r) 2, f = 10 kHz, 180 kHz deviation) The noisecanceller responds to the whisker components generated by this overmodulation, resulting in distortion of theaudio output. (The whisker components due to the overmodulation are generated by the band of the ceramicfilter in the tuner.) This can be prevented as follows. The incorrect operation due to the overmodulation can beeliminated by removing the whisker components due to the overmodulation as described above with the low-pass filter consisting of a 1 kΩ resistor and 220 pF capacitor as shown in the figure. Note, however, that the FMseparation characteristics in the high band and the AM frequency characteristics will change.

AM detector

42

C42

1 kΩ10 kΩ

1 kΩTo 31PIN

Pilot det

+–

Detector Output – f [dB]

–20

–15

–10

–5

0

5

0.01 0.1 1 10

Modulation frequency [kHz]O

utpu

t [dB

]

C42 = 0.47u C42 = 1u

H1 W12.5OU

–2.5OU–19.00 µs 981.00 µs

IF audio output f = 10 kHz, 180 kHz dev

31 30

IF output Noise canceller input1 kΩ

1 µF2200 pF

+ –

No.8085-31/41

LA1776M

7.Multiplex Block7-1.Pilot Canceller

The pin 18 pilot canceller signal waveform is a 19 kHz signal in which the third harmonic is not present. Sincethis signal has the same phase as the pilot signal, no capacitor is required between pin 18 and ground. Since thethird harmonic is not present, excellent pilot cancellation in both the left and right channels can be acquired byadjusting the circuit with a variable resistor.

7-2.Separation Adjustment (pin 19)

The separation is adjusted by adjusting the sub-decoder input level with the pin 19 variable resistor VR.Adjusting VR only changes the sub-channel modulation. It does not change the monaural (main) output level.Degradation of high band separation in the decoder can be avoided if the impedance of the external capacitorvalue (C) is made enough smaller than the impedance of VR in the sub-channel signal frequency band (23 to 53kHz).

8. MRC Block

17

30

1110

6800 pF

18

0.01 µF 50 kΩ

PILOTCANCEL

GATE

Noise cancellerinput

To the multiplexer

–

19

5 kΩ

0.047 µF C

To the subdecoder

20 kΩ

Larger

24 32 27

MRC

5.5 kΩ

30 kΩ

5.5 kΩ

1 kΩ

DC BUFFER

FM Vsm

FM/AM Vsm

HPF: C26, 30KLPF: C32Gain: R26

7 µA

0.22 µF

C263.3 µF

100 Ω

10 kΩ

100 kΩ1000 pFR2651 kΩ

C27C24 C32

26

+ +

*: When the AC component is removed with C24.

No.8085-32/41

LA1776M

8-1.The S-meter DC input voltage is set by the variable resistor R1 connected to pin 32. While it is often said that acurve such as that shown in figure 59 is ideal for separation control when multipath interference occurs, if thepin 32 voltage is too high, separation control in strong field reception, as shown in figure 60, will becomeimpossible. Thus it is desirable to adjust the circuit so that the pin 32 voltage remains under 2 V whensaturated.

8-2. The time constant with which the MRC circuit controls the separation is determined by an internal 100 Ωresistor and C2 during charge and by a constant current of 7 µA and C2 during discharge.

AC 60%AC 30%

AC 30%

Field strength

SE

P (

dB)

Field strength

SE

P (

dB)

ACø%

ACø%

AC 100%

AC 60%AC 100%

41

+

VCC VCC

100 Ω

7 µFC2

No.8085-33/41

LA1776M

Crystal Oscillator ElementKinseki, Ltd.

Frequency: 10.26 MHzCL: 20 pFModel No.: HC-49/U-S

Coil SpecificationsSumida Electronics, Ltd.

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

3

2

4

1 6

S

3

2

4

1 6

S

3

2

4

1 6

S

S3

2

4

1 6

S

3

2

4

1 6

S

3

2

48

71 6

S

SC1

C2

3

2

4

1 6

S S

0.1ø2UEW

AM FILTER (SA-1051)[AM Block]

[FM Block]

AM OSC (SA-359)

AM IF1 (SA-264) AM IF2 (SA-1063)

AM loading (SA-1062)

AM RF amplifier (RC875-222J)

AM ANT IN (SA-1048)

FM RF (SA-1060) FM ANT (SA-1061)

FM OSC (SA-1052) FM MIX (SA-266)

FM DET (SA-208)

No.8085-34/41

LA1776M

0.1ø2UEW

AM FILTER (A2861BIS-15327)[AM Block]

[FM Block]

AM OSC (V666SNS-214BY)

AM IF1 (7PSGTC-5001A) AM IF2 (7PSGTC-5002Y)

AM loading (269ANS-0720Z)

AM RF amplifier (187LY-222)

AM ANT IN (385BNS-027Z)

FM RF (V666SNS-208AQ) FM ANT (V666SNS-209BS)

FM OSC (V666SNS-205APZ) FM MIX (371DH-1108FYH)

FM DET (DM600DEAS-8407GLF)

1 2 3

6 4

3

2

4

1 6 0.1ø2UEW

3

2

4

1 6 0.05ø3UEW

3

2

4

1 6 0.05ø3UEW

3

2

4

1 6 0.05ø3UEW

3

2

4

1 6 S

S

ø0.1 – 2UEW

3

2

4

1 6 Sø0.1 – 2UEW

3

2

4

1 6 Sø0.12 – 2UEW

3

2 5

4

1 6 S

S

ø0.07 – 2UEW

3

2

4

1 6 0.07ø2MUEW

3

2

4

1 6

S

S

The Toko Electric Corporation

No.8085-35/41

LA1776M

1 2 3

6 4

3

2

4

1 6

S

3

2

4

1 6S S

S S

180 pF

1-3:20 µH3-4:120 pF

62.7 nH

30 mH

180 pF

5.1 µH

100 µH

105.5 nH

1-2:100 pF2-3:100 pF

3

2

4

1 6

S

3

2

4

1 6

S

3

2

4

1 6

S

S3

2

4

1 6

S

3

2

4

1 6

S S

S

2.2 mH

AM FILTER (000021055)[AM Block]

[FM Block]

AM OSC (000021056)

AM IF1 (000021057) AM IF2 (000021059)

AM loading (000021061)

AM RF amplifier (000021063)

AM ANT IN (000021062)

FM RF (000021064) FM ANT (000021065)

FM OSC (000021066) FM MIX (000021067)

FM DET (010021075)

3

2 5

4

1 6

3

2

4

1 6

S

3

2

4

1 6

Sagami Elec Co., Ltd.

No.8085-36/41

LA1776M

-10

-20

-30

-40

-50

-60

-70

10 8

7

6

5

4

3

2

1

0

8

7

6

5

4

3

2

1

0

4

3

2

1

0

0

-20 -10 0 20 3010 40 50 60 70 80 90 100 110 120 130

-10

-20

-30

-40

-50

-60

-70

10

0

-20 -10 0 20 3010 40 50 60 70 80 90 100 110 120 130

6

5

4

3

2

1

0

8

7

-20 -10 0 20 3010 40 50 60 70 80 90 100 110 120

-50

-40

-30

-20

-10

-60

10

0

40 60 80 100 140120

-50

-40

-30

-20

-10

-60

10

0

40 60 80 100 140120

-10

-20

-30

-40

-50

-60

-70

10

0

-20 -10 0 20 3010 40 50 60 70 80 90 100 110 120 130

6

5

4

3

2

1

0

-2

-4

-6

-8

-10

2

0

10 2 3 5 7 2 3 5 7 2 3 5 7100 1k 10k

7

6

5

4

3

2

1

0

9

8

-20 -10 0 20 3010 40 50 60 70 80 90 100 110 120 130

S

Vsm

AMR(1K,30%)

N

RF AGC

THD (100%)

ANT D

THD (30%)

S

N

Vsm

output

THD (80%)

THD (30%)

SEP(R) SEP(L)

Vsnc

THD (80%)

RF AGC

THD (30%)

S(80 dBµ)

N (80 dBµ)N (80 dBµ)

S (60 dBµ)S (40 dBµ)

N (60 dBµ)

N (60 dBµ)

N (40 dBµ)

N(80 dBµ)

S(60 dBµ)S(40 dBµ)

N(60 dBµ)N(80 dBµ)

N(60 dBµ)

N(40 dBµ)

FM Input/Output CharacteristicsO

utpu

t – d

B

Out

put –

dB

Out

put –

dB

Sep

arat

ion,

Sep

– d

BV

snc

– V

AG

C –

VT

otal

har

mon

ic d

isto

rtio

n, T

HD

– %

Tot

al h

arm

onic

dis

tort

ion,

TH

D –

%S

-met

er v

olta

ge, V

sm –

VT

otal

har

mon

ic d

isto

rtio

n, T

HD

– %

S-m

eter

vol

tage

, Vsm

– V

S-m

eter

vol

tage

, Vsm

– V

Field strength – dB µ Field strength – dB µ

Field strength – dB µ

Field strength – dB µ Frequency, fm – Hz

fu input level – dBµ fud input level – dBµ

Field strength – dB µ

FM Input/Output Characteristics

AM Frequency Characteristics

AM Input/Output Characteristics

AM Input/Output Characteristics

AM Two-Signal Interference SuppressionCharacteristics (∆ 400 kHz)

AM Two-Signal Interference SuppressionCharacteristics (∆ 40 kHz)

FM Separation Input/Output Characteristics

Tot

al h

arm

onic

dis

tort

ion,

TH

D –

%

S (80 dBµ)

ANT D

No.8085-37/41

LA1776M

350

300

250

200

400

-40 -30 -20 -10 0 20 3010 40 50 60 70 80 90

-40 -30 -20 -10 0 20 3010 40 50 60 70 80 90

-40 -30 -20 -10 0 20 3010 40 50 60 70 80 90

-40 -30 -20 -10 0 20 3010 40 50 60 70 80 90

70

60

50

40

80

-40 -30 -20 -10 0 20 3010 40 50 60 70 80 90

-40 -30 -20 -10 0 20 3010 40 50 60 70 80 90

-40 -30 -20 -10 0 20 3010 40 50 60 70 80 90

-40 -30 -20 -10 0 20 3010 40 50 60 70 80 90

10

5

0

-5

20

15

80

70

60

50

100

90

1

0

3

2

2.5

2.6

2.7

2.8

2.4

3

2.9

20

10

0

40

30

30

20

10

0

50

40

output S/N

AMR (80 dB)

AMR (50 dB)

Q.S (S/N = 50)

U.S (S/N = 30)

SEP (80 dBµ)

SEP (35 dBµ)

–3dB (mute on)

–3dB (mute off)

W-AGC

N-AGC

THD (mono)

THD (main)

Vref

Vafc

FM Temperature CharacteristicsO

utpu

t – m

V r

ms

–3dB

L.S

– d

BN

-AG

C, W

-AG

C o

n le

vel –

dB

µT

otal

har

mon

ic d

isto

rtio

n, T

HD

– %

Q.S

., U

.S.,

Noi

se c

onve

rgen

ce –

dB

µ, d

BS

/N, A

MR

– d

BS

epar

atio

n, S

ep –

dB

Vaf

c,V

ref –

V

Ambient temperature, Ta – ºC Ambient temperature, Ta – ºC





FM Temperature Characteristics




FM Temperature CharacteristicsFM Temperature Characteristics


Noise convergence

No.8085-38/41

LA1776M

0.4

0.3

0.2

0.1

0

-0.5

-0.4

-0.3

-0.2

-0.1

0.5

-40 -30 -20 -10 0 20 3010 40 50 60 70 80 90

-40 -30 -20 -10 0 20 3010 40 50 60 70 80 90

-40 -30 -20 -10 0 20 3010 40 50 60 70 80 90

-40 -30 -20 -10 0 20 3010 40 50 60 70 80 90

120

110

100

90

80

130

-40 -30 -20 -10 0 20 3010 40 50 60 70 80 90

-40 -30 -20 -10 0 20 3010 40 50 60 70 80 90

-40 -30 -20 -10 0 20 3010 40 50 60 70 80 90

-40 -30 -20 -10 0 20 3010 40 50 60 70 80 90

40

20

0

-80

-60

-40

-20

80

60

50

40

70

60

300

250

200

400

350

40

50

60

30

80

70

30

25

20

40

35

4

3

2

1

0

6

5

VnullSD bandwidth

SD on level

Vsm (80 dBµ)

Vsm (70 dBµ)

Vsm (60 dBµ)

Vsm (50 dBµ)

Vsm (40 dBµ)

Vsm (30 dBµ)

S/N

AMR (60 dBµ)

SD bandwidth (+)

96.3 MHz beating worst case

107 MHz beating worst case

FM Temperature CharacteristicsV

null

– V

SD

ban

dwid

th –

kH

zS

igna

l-to-

nois

e ra

tio w

ith IF

bea

ting

– dB

outp

ut –

mV

rms

SD

on

leve

l – d

Bµ

SD

ban

dwid

th –

kH

zS

-met

er v

olta

ge, V

sm –

VS

/N, A

MR

– d

B










FM Temperature CharacteristicsFM Temperature Characteristics


output

SD bandwidth (–)

No.8085-39/41

LA1776M

70

60

50

40

30

80

-40 -30 -20 -10 0 20 3010 40 50 60 70 80 90

-40 -30 -20 -10 0 20 3010 40 50 60 70 80 90

-40 -30 -20 -10 0 20 3010 40 50 60 70 80 90

-40 -30 -20 -10 0 20 3010 40 50 60 70 80 90

50

40

30

20

60

-40 -30 -20 -10 0 20 3010 40 50 60 70 80 90

-40 -30 -20 -10 0 20 3010 40 50 60 70 80 90

-40 -30 -20 -10 0 20 3010 40 50 60 70 80 90

80

75

70

90

85

1

0

3

2

2

0

6

4

50

45

40

60

55

4

3

2

1

0

6

5

ST S/N (15 kHz)

ST S/N (OFF)

–3 dB (mute on)

IF count buff

N-AGC on

SD on level

THD (mono)

THD (main)

FM Temperature CharacteristicsS

T S

/N –

dB

N-A

GC

on

LEV

EL

– dB

µT

otal

har

mon

ic d

isto

rtio

n, T

HD

– %

S-m

eter

vol

tage

, Vsm

– V

SD

on

LEV

EL

– dB

µ–3

dB

L.S

– d

Bµ

IF c

ount

BU

FF

LE

VE

L –

mV

rms












Vsm (90 dBµ)Vsm (80 dBµ)

Vsm (70 dBµ)

Vsm (60 dBµ)

Vsm (50 dBµ)

Vsm (40 dBµ)

Vsm (30 dBµ)

No.8085-40/41

LA1776M

60

50

40

70

-40 -30 -20 -10 0 20 3010 40 50 60 70 80 90

-40 -30 -20 -10 0 20 3010 40 50 60 70 80 90

-40 -30 -20 -10 0 20 3010 40 50 60 70 80 90

35

30

25

20

40

-40 -30 -20 -10 0 20 3010 40 50 60 70 80 90

-40 -30 -20 -10 0 20 3010 40 50 60 70 80 90

-40 -30 -20 -10 0 20 3010 40 50 60 70 80 90

4

3

2

1

0

6

5

3

2

1

0

5

4

50

45

40

60

55

-5

0

-1

-2

-3

-4

S/N

AGC FOMPractical sensitivity

SD

Vsm (130 dBµ) W-AGC

W-AGC (SEEK)

N-AGC

Vsm (74 dBµ)

Vsm (30 dBµ)

Vsm (–20 dBµ)

THD (0.1 k, 80 %)

100 Hz attenuationTHD (0.1 k, 30 %)

THD (1 k, 80 %)

THD (1 k, 30 %)

AM Temperature CharacteristicsS

/N, A

GC

FO

M –

dB

Vsm

– V

Tot

al h

arm

onic

dis

tort

ion,

TH

D –

%

N-A

GC

, W-A

GC

on

LEV

EL

– dB

µP

ract

ical

sen

sitiv

ity –

dB

µ, S

D o

n –

dBµ

AM

LC

(10

0 H

z) –

dB





AM Temperature Characteristics





PS No.8085-41/41

LA1776M

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 guaranteesof the performance, characteristics, and functions of the described products as mounted in the customer'sproducts 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's products or equipment.

SANYO Electric Co., Ltd. strives to supply high-quality high-reliability products. However, any and allsemiconductor 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 sothat these kinds of accidents or events cannot occur. Such measures include but are not limited to protectivecircuits and error prevention circuits for safe design, redundant design, and structural design.

In the event that any or al l 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 expor ted without obtaining the expor t l icense from the authorit iesconcerned in accordance with the above law.

No part of this publication may be reproduced or transmitted in any form or by any means, electronic ormechanical, 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 toproduct/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 notguaranteed for volume production. SANYO believes information herein is accurate and reliable, butno guarantees are made or implied regarding its use or any infringements of intellectual property rightsor other rights of third parties.

This catalog provides information as of July, 2005. Specifications and information herein are subject

to change without notice.

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