SANYO LA1838 Datasheet

Ordering number : EN5888

40999RM (OT) No. 5888-1/9

Overview

The LA1838 is designed for use in home stereo systems
and is a single-chip tuner IC that provides electronic
tuning functions for AM, FM IF, and MPX reception. It is
optimal for use in products that adopt an automatic tuning
system based on an IF count.

Functions

• AM: RF amplifier, mixer, oscillator, IF amplifier,
detector, AGC, oscillator buffer, S-meter,
narrow-band SD, IF buffer

• FM IF: IF amplifier, quadrature detector, S-meter, SD
(signal detection), S-curve detection, IF buffer
output

• MPX: PLL stereo decoder, stereo display, forced
monaural, VCO stop, post amplifier, audio
muting, adjacent channel interference rejection
function

Features

• Integrated MPX VCO (External components are no
longer required.)

• Built-in adjacent channel interference rejection function
(third and fifth order)

• Adjustment-free FM detector circuit (Uses a ceramic
discriminator.)

• The AM and FM SD sensitivities can be set
independently.

• The AM and FM output levels can be set independently.

• Improved useable AM sensitivity and strong field
distortion characteristics.

Package Dimensions

unit: mm

3061-DIP30S

1

15

30

16

1.15 1.78

27.2

0.25

10.16

8.6

0.48 0.95

4.25

3.2

4.95max

0.51min

SANYO: DIP30S

[LA1838]

LA1838

SANYO Electric Co.,Ltd. Semiconductor Company

TOKYO OFFICE Tokyo Bldg., 1-10, 1 Chome, Ueno, Taito-ku, TOKYO, 110-8534 JAPAN

Single-Chip Home Stereo IC with Electronic

Tuning Support

Monolithic linear IC

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’s
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.

-40

0

300

200

100

400

-20

500

550

600

20 60 10004080

Ambient temperature, Ta —°C

Allowable power dissipation, Pdmax — mW

Pdmax-Ta

Specifications

Maximum Ratings at Ta = 25°C

Operating Conditions at Ta = 25°C

Operating Characteristics at Ta = 25°C, VCC= 9 V, in the specified test circuit.

No. 5888-2/9

LA1838

Parameter Symbol Conditions Ratings Unit

Maximum supply voltage V

CC

max 12 V
Allowable power dissipation Pd max Ta ≤ 70°C 550 mW
Operating temperature Topr –20 to +70 °C
Storage temperature Tstg –40 to +125 °C

Parameter Symbol Conditions Ratings Unit

Recommended supply voltage V

CC

9 V

Operating supply voltage range V

CC

op 7 to 11 V

Parameter Symbol Conditions

Ratings

Unit

min typ max
[FM Mono Characteristics] fc = 10.7 MHz, fm = 1 kHz
Current drain I

CCO-FM

With no input signal 18 31 44 mA

Demodulator output V

OFM

100 dBµ, 100% modulation, the pin 16 output 730 1100 1460 mVrms

Channel balance C.B-mono

100 dBµ, 100% modulation, the pin 16 output/the

–1.5 0 +1.5 dB

pin 17 output

Total harmonic distortion (mono) THD

FM

100 dBµ, 100% modulation, the pin 16 output 0.3 1.5 %

Signal-to-noise ratio S/N

FM

100 dBµ, 100% modulation, the pin 16 output 70 77 dB

AM rejection ratio AMR 100 dBµ, AM 30% modulation, the pin 16 output 40 55 dB

Input limiting voltage –3dBL.S

100 dBµ, 100% modulation, referenced to the output,

26 32 38 dBµ

the input when the output is down by –3 dB

LED indicator on sensitivity SD

On-FM

47 57 67 dBµ

LED indicator on bandwidth SD

BW

100 dBµ 130 210 300 kHz

IF counter buffer output V

IFBuff-FM

100 dBµ, the pin 13 output 80 120 160 mVrms

S-meter output

V

SM-FM1

0 dBµ, the pin 11 output 0 0.1 0.5 V

V

SM-FM2

100 dBµ, the pin 11 output 3.6 4.3 5.0 V
Mute attenuation Mute-Att 100 dBµ, 100% modulation, the pin 16 output 75 85 dB
[FM Stereo Characteristics] fc = 10.7 MHz, fm = 1 kHz, L + R = 90%, Pilot = 10%, 100 dBµ
Separation (left) SepLLeft channel modulated. The pin 16 output/the pin 17 output 30 45 dB
Separation (right) SepRRight channel modulated. The pin 17 output/the pin 16 output 30 45 dB
Stereo on level ST

ON

The pilot modulation such that V7 falls under 0.7 V 1.3 2.7 5 %
Stereo off level ST

OFF

The pilot modulation such that V7 rises to over 4.5 V 1.5 %
Total harmonic distortion (main) THD-main Left + right modulation. The pin 16 output. 0.3 1.5 %

fs = 113 kHz, Vs = 90%, pilot = 10%

Brej-3rd The left - right modulation 1 kHz demodulated output 40

dB

Adjacent channel rejection ratio

with respect to the pin 16 output

fs = 189 kHz, Vs = 90%, pilot = 10%

Brej-5th The left - right modulation 1 kHz demodulated output 40

dB

with respect to the pin 16 output
[AM Characteristics] fc = 1000 kHz, fm = 1 kHz
Current drain I

CCO-AM

With no input signal 15 25 35 mA

Detector output

V

OAM1

23 dBµ, 30% modulation, the pin 16 output 100 180 360 mVrms

V

OAM2

80 dBµ, 30% modulation, the pin 16 output 200 320 500 mVrms

Signal-to-noise ratio

S/N

AM1

23 dBµ, 30% modulation, the pin 16 output 18 22 dB

S/N

AM2

80 dBµ, 30% modulation, the pin 16 output 49 55 dB

Total harmonic distortion

THD

AM1

80 dBµ, 30% modulation, the pin 16 output 0.4 1.2 %

THD

AM2

80 dBµ, 80% modulation, the pin 16 output 1.0 4.0 %
LED indicator on sensitivity SD

On-AM

17 27 37 dBµ

Local oscillator buffer output V

OSC-AM

With no input signal, the pin 30 output 110 160 220 mVrms
IF counter buffer output V

IFBuff-AM

80 dBµ, 100% modulation, the pin 13 output 160 220 300 mVrms
ST - IF output V

STIF-AM

80 dBµ, 100% modulation, the pin 7 output 16 34 48 mVrms
S-meter output V

SM-AM

0 dBµ, 100% modulation 0 0 0.2 V

Block Diagram

AC Test Circuit

No. 5888-3/9

LA1838

ALC

V

CC

GND

AGC

DETAM IF

FM I F

REG

L.P.F

MUTE

BUFF

AM

OSC

AM

MIX

AM

RF.AMP

AM

S-METER

DECODER

ANTI

-

BIRDIE

AM/FM

IF-BUFF

TUNING

DRIVE

STEREO

DRIVE

FM

S-METER

S-CURVE

SD

COMP

FM

DET

T00147

30 29 28 27 26 25 24 23 22 21 20 19 18 17 16

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

P-DET

STEREO

SW

VCO

304kHzFF38k

FF

19k

∠

2

-

π

FF

19k

∠θ

PILOT

DET

+

++

+

+

+

+

+

+

+

L.P.F

+

OSC
BUFF

FM IN
(10.7MHz)

AM IFT

TU

-

LED

ST

-

LED

AM

-

IF

FM V

SM

AM V

SM

(SD

-

ADJ)

AM/FM

IF

-

BUFF

MUTE

AM NARROW

SD

VT

FM SD

ADJ

AM AGC

AM-STEREO
L/R-INPUT

OSC

RF

FM SD
BAND-W

L

L

-

OUT

R

-

OUT

R

AM

MONO

V

CC

FM ST

0.047µF

0.047

µ

F

0.047

µ

F

0.047

µ

F

0.047

µ

F

10

µ

F

0.47

µ

F

SEEK1000pF

1

µ

F

1

µ

F

1

µ

F

1000pF

47

µ

F

0.047µF

0.01µF

0.033

µ

F

10

µ

F

10

µ

F

0.033

µ

F

10µF

0.047

µ

F

0.047µF

33

µ

F

3.3

µ

F

22

µ

F

1000pF

39pF

20pF

1000pF

39mH

3k

Ω

50

Ω

18k

Ω

3.3kΩ3.3k

Ω

5.1k

Ω

300

Ω

75

Ω

68k

Ω

330

Ω

51

Ω

68k

Ω

5k

Ω

5k

Ω

5k

Ω

10k

Ω

3k

Ω

L.P.F

T00148

30 29 28 27 26 25 24 23 22 21 20 19 18 17 16

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

+

+

+ +

+

+

+

+

+

+

+

L.P.F

+

OSC

BUFF

(1.45MHz)

FM IN
(10.7MHz)

SD ST

AM

-

ST

V

SM

V

SM

NORMAL

AM-IN
(1MHz)

OSC

REG

AFC

L

-

OUT

R

-

OUT

MONO

V

CC

FM

AM

STEREO

450kHz

( )

FM

AM

V

DD

IF

-

BUFF

9.0V

LA1838

T1

T2

CDA10.7MGI-C
(For use as the DUT socket board)

The CDA10.7MG74 must be used for actual production models.
(Series resistance: 270 Ω)

*

T1: HW-50425
T2: YD-1073-1