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

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

300

200

100

400

-20

500

550

600

100

Ambient temperature, Ta --

Allowable power dissipation, Pdmax -- mW

Pd max - Ta

Specifications

Maximum Ratings

at Ta = 25°C

Operating Conditions

at Ta = 25°C

Operating Characteristics

at Ta = 25°C, V

= 9 V, in the specified test circuit.

No. 5888-2/9

LA1838

Parameter

Symbol

Conditions

Ratings

Unit

Maximum supply voltage

max

Allowable power dissipation

Pd max

70°C

550

Operating temperature

Topr

20 to +70

°C

Storage temperature

Tstg

40 to +125

°C

Parameter

Symbol

Conditions

Ratings

Unit

Recommended supply voltage

Operating supply voltage range

7 to 11

Parameter

Symbol

Conditions

Ratings

Unit

min

typ

max

[FM Mono Characteristics] fc = 10.7 MHz, fm = 1 kHz

Current drain

CCO-FM

With no input signal

Demodulator output

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

+1.5

pin 17 output

Total harmonic distortion (mono)

THD

100 dBµ, 100% modulation, the pin 16 output

0.3

1.5

Signal-to-noise ratio

S/N

100 dBµ, 100% modulation, the pin 16 output

AM rejection ratio

AMR

100 dBµ, AM 30% modulation, the pin 16 output

Input limiting voltage

3dBL.S

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

dBµ

the input when the output is down by 3 dB

LED indicator on sensitivity

On-FM

dBµ

LED indicator on bandwidth

100 dBµ

130

210

300

kHz

IF counter buffer output

IFBuff-FM

100 dBµ, the pin 13 output

120

160

mVrms

S-meter output

SM-FM1

0 dBµ, the pin 11 output

0.1

0.5

SM-FM2

100 dBµ, the pin 11 output

3.6

4.3

5.0

Mute attenuation

Mute-Att

100 dBµ, 100% modulation, the pin 16 output

[FM Stereo Characteristics] fc = 10.7 MHz, fm = 1 kHz, L + R = 90%, Pilot = 10%, 100 dBµ

Separation (left)

Sep

Left channel modulated. The pin 16 output/the pin 17 output

Separation (right)

Sep

Right channel modulated. The pin 17 output/the pin 16 output

Stereo on level

The pilot modulation such that V7 falls under 0.7 V

1.3

2.7

Stereo off level

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

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

with respect to the pin 16 output

[AM Characteristics] fc = 1000 kHz, fm = 1 kHz

Current drain

CCO-AM

With no input signal

Detector output

OAM1

23 dBµ, 30% modulation, the pin 16 output

100

180

360

mVrms

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

S/N

AM2

80 dBµ, 30% modulation, the pin 16 output

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

On-AM

dBµ

Local oscillator buffer output

OSC-AM

With no input signal, the pin 30 output

110

160

220

mVrms

IF counter buffer output

IFBuff-AM

80 dBµ, 100% modulation, the pin 13 output

160

220

300

mVrms

ST - IF output

STIF-AM

80 dBµ, 100% modulation, the pin 7 output

mVrms

S-meter output

SM-AM

0 dBµ, 100% modulation

0.2

Block Diagram

AC Test Circuit

No. 5888-3/9

LA1838

ALC

GND

AGC

DET

AM I F

FM I F

REG

L.P.F

MUTE

BUFF

OSC

MIX

RF.AMP

S-METER

DECODER

ANTI- BIRDIE

AM/FM

I F-BUFF

TUNING

DRIVE

STEREO

DRIVE

S-METER

S-CURVE

COMP

DET

T00147

P-DET

STEREO

VCO

304kHz

38k

19k

PILOT

DET

L.P.F

OSC
BUFF

FM IN
(10.7MHz)

AM IFT

L
E

I
F

(
S

-A

J
)

/
F

I
F

-B

V T

AM -STEREO
L / R - INPUT

FM SD
BAND -W

L-OUT R-OUT

MONO

0.047

0.47

SEEK1

0pF

1
00

0pF

0.047

0.01

0.033

0.047

3.3

1
00

0pF

39pF

20pF

1000pF

39mH

18k

3.3k

5.1k

300

68k

330

68k

10k

L.P.F

T00148

L.P.F

OSC

BUFF

(1.45MHz)

FM IN
(10.7MHz)

AM - ST

NORMAL

AM -IN

(1MHz)

OSC

REG

AFC

L-OUT R-OUT

MONO

STEREO

450kHz

( )

I
F

BUFF

9.0V

LA1838

T 2

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

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

)

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

Pin No.

Pin function

Pin voltage

Notes

Equivalent circuit

Vreg 1.4

Vreg

Coil Specifications

· AM oscillator (for the DUT)

HW-50425 (Mitsumi)

Pin Functions

· IFT

YD-1073-1 (Mitsumi)

No. 5888-4/9

LA1838

A10633

86T

L = 270

YD-1073

SFU450B

A10634

58T

94T

= 450 kHz

= 110

A 180-pF capacitor is built in
With an external SFU450B

FM IF input

AM mixer output

Input impedance r

= 330

Connect the mixer coil between this pin and V

A10635

A10636

A10635

Vreg

FM IF input
bypass

Also used for the MPX regulator filter

A10637

Vreg

0 V

AM IF input

GND

Input impedance r

= 2 k

A10638

TU-LED

ST-LED,

AF-IF output

6
7

Active low

Open collector

AM stereo IF output (pin 7)

The influx current must be held under 150 µA.

A10639

FM detector

The CDA10.7 MG74 (Murata Mfg. Co., Ltd.) is
recommended as the ceramic discriminator. A
device with a series resistance of 270

must be

used.

Continued on next page.

Continued from preceding page.

No. 5888-5/9

LA1838

Pin No.

Pin function

Pin voltage

Notes

Equivalent circuit

1.3 V

AM narrow band
CF connection

Recommended narrow band CF: BFU450 C4N
(Murata Mfg. Co., Ltd.)

When the narrow band SD function is not used,
bypass this circuit with a 50

resistor and a

0.047 µF capacitor in series.

A10640

0 V

FM S-meter output

= 8 k

A10641

0 V (AM)

AM S-meter
output

The AM SD sensitivity is adjusted with an external
resistor connected between this pin and ground

A10642

0 V

AM/FM IF buffer
output,

Output control
switch
(mute switch)

V13

0.5 V: Reception state

1.4 V

V13

2.2 V: IF buffer output on

V13

3.5 V: IF buffer output and muting on

A10643

1.4 (FM)

0 V (AM)

Phase comparator
low-pass filter
(AM/FM switching)

The device operates in AM mode when this pin is
connected to ground through a resistor.

Limit values for the resistor:
2.7 k

(When V

= 7 V)

3.9 k

(8 V), 5.1 k

(9 V)

6.2 k

(10 V), 7.5 k

(11 V)

A10644

1.0

Pilot detector low-
pass filter (Forced
mono) (VCO stop)

The device is forced to monaural when a current of
over 50 µA flows from this pin.

The VCO is stopped if this pin is connected to
ground.

The limit values for the resistor are the same as
those for pin 14.

A10645

Vreg

Post-amplifier
inputs and outputs

Output impedance r

= 200

Pin 16: Right output, pin 17: Left output

Inverting input pins
Pin 18: Right input, pin 19: Left input

= 33 k

A10646

3.5 V

MPS outputs

Output impedance r

= 3.3 k

Pin 20: Right deemphasis
Pin 21: Left deemphasis

A10647

Continued on next page.

Continued from preceding page.

No. 5888-6/9

LA1838

Pin No.

Pin function

Pin voltage

Notes

Equivalent circuit

2.9 V

MPX input

Input impedance r

= 20 k

A10648

2.8 V (FM)

2.8 V (AM)

FM demodulator
output

Output impedance r

= 3.0 k

The channel separation can be adjusted with an
external capacitor connected between this pin and
ground.

The V

sub/V

main ratio is set to be about 0 dB.

A10649

0 V (FM)

0.5 V (AM)

AM detector
output

Output impedance r

= 3.3 k

The AM frequency characteristics can be adjusted
by modifying the time constant of the circuit
connected between this pin and pin 22 and
between this pin and ground.

A10650

0 V (FM)

0.5 V (AM)

AM AGC

The resistance of the built-in resistor R is 11 k

A10651

Vreg

AFC

The FM SD bandwidth can be adjusted with the
external resistor connected between this pin and
pin 28

A10652

Vreg

AM RF input

Must be used at the same potential as pin 28

A10653

Vreg

REG

Vreg = 3.6 V

A10654

Vreg

OSC

Connect the oscillator coil between this pin and
pin 28

A10655

1.6 V (FM)

1.3 V (AM)

Oscillator buffer
output,

FM SD sensitivity
adjustment

The FM SD sensitivity can be adjusted with an
external resistor connected between this pin and
ground.

Output impedance r

= 200

A10656

No. 5888-7/9

LA1838

t

--

Distortion vs. Frequency Characteristics

Separation vs. Frequency Characteristics

Frequency, freq -- kHz

Frequency, f

-- kHz

Frequency, freq -- kHz

Adjacent Channel Rejection Ratio

110

130

150

170

230

210

190

-10

-20

-30

-40

-50

-60

-70

-80

-90

0.01

2 3

5 7

0.1

1.0

2 3

5 7

2 3

5 7

2 3

0.1

1.0

0.01

2 3

5 7

2 3

5 7

0.1

1.0

t
a
l

h

a
r
m

i
c

d

i
s
t
o

r
t
i
o

,

T

a
n

e
l

s
e
p

a
r
a
t
i
o

,

S

e
p

Capture Range Characteristics

Pilot -- mV

SD Sensitivity Adjustment

Rsdadj -- k

a
p

t
u

r
e

r
a
n

e

--

-6

-2

-4

AM FM

Overall FM Characteristics

t
p

t
,

--

Input, -- dB

100

120

-10

-20

-30

-40

-50

-60

-70

-100

-90

-80

Out

AM Out

Noise

= 9 V

= 10.7 MHz

= 1 kHz ,75 kHzdev

AM = 30% mod

FM THD and V

Characteristics

Input, -- dB

t
a
l

h

a
r
m

i
c

d

i
s
t
o

r
t
i
o

,

T

-
m

e
t
e
r

o

t
p

t
,

V

110

100

120

VSM

THD

FM THD vs. Band Characteristics

Frequency, f

-- MH

10.60 10.62 10.64 10.66 10.68

10.72 10.74 10.76 10.78

10.70

10.80

3.0

4.0

2.0

1.0

5.0

t
a
l

h

a
r
m

i
c

d

i
s
t
o

r
t
i
o

,

T

= 9 V

= 100 dB

= 1 kHz , 75 kHzdev

Sep

-R

Sep-L

IF = 10.7 MHz, 100 dB

, 75 kHzdev

= 90%

PILOT = 10%
Referenced to the
L-R demodulated output

LA1836

LA1838

No. 5888-8/9

LA1838

Distortion vs. Ambient Temperature Characteristics

Output voltage, V

-- dBV

Frequency, f

-- kHz

Ambient temperature, Ta --

Frequency, fm -- kHz

Ambient temperature, Ta --

0.01

-40

-10

-5

-30

-35

-25

-20

-15

2 3

5 7

2 3

5 7

0.1

1.0

0.01

-40

-10

-5

-30

-35

-25

-20

-15

2 3

5 7

2 3

5 7

0.1

1.0

-40

0.1

1.0

-20

100

-40

-20

100

Channel separation, Sep -- dB

Total harmonic distortion, THD -- %

AM Detector Output Frequency Characteristics (1)

AM Detector Output Frequency Characteristics (2)

Separation vs. Ambient Temperature Characteristics

Sep - L

Sep - R

S/N Mono

THD Mono

THD Main

THD st

THD sub

S/N Stereo

0.01

C = 0.022

C = 0.047

C = 0.01

R = 10 k

R = 33 k

R = 18 k

Overall AM Characteristics

AM THD and V

Characteristics

Input, -- dB

Output, -- dBm

Total harmonic distortion, THD -- %

S-meter output, V

-- V

5.0

4.0

4.5

3.5

3.0

2.5

2.0

1.5

1.0

0.5

-20

100

120

140

-20

100

140

120

-10

-20

-30

-40

-50

-60

-70

-80

THD = 30%mod

THD = 80%mod

Out

Noise

= 9 V

= 1 MHz

= 1 kHz , 30%mod

= 9 V

= 1 MHz

= 1 kHz , 30%mod

350

300

150

100

200

250

SD Band Adjustment Characteristics

Radj -- k

BW --

kHz

No. 5888-9/9

LA1838

This catalog provides information as of April, 1999. Specifications and information herein are subject to
change without notice.

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's
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's products or equipment.

SANYO Electric Co., Ltd. strives to supply high-quality high-reliability products. However, any and all
semiconductor products fail with some probability. It is possible that these probabilistic failures could
give rise to accidents or events that could endanger human lives, that could give rise to smoke or fire,
or that could cause damage to other property. When designing equipment, adopt safety measures so
that these kinds of accidents or events cannot occur. Such measures include but are not limited to protective
circuits and error prevention circuits for safe design, redundant design, and structural design.

In the event that any or all SANYO products (including technical data, services) described or contained
herein are controlled under any of applicable local export control laws and regulations, such products must
not be exported without obtaining the export license from the authorities concerned in accordance with the
above law.

No part of this publication may be reproduced or transmitted in any form or by any means, electronic or
mechanical, including photocopying and recording, or any information storage or retrieval system,
or otherwise, without the prior written permission of SANYO Electric Co., Ltd.

Any and all information described or contained herein are subject to change without notice due to
product/technology improvement, etc. When designing equipment, refer to the "Delivery Specification"
for the SANYO product that you intend to use.

Information (including circuit diagrams and circuit parameters) herein is for example only; it is not
guaranteed for volume production. SANYO believes information herein is accurate and reliable, but
no guarantees are made or implied regarding its use or any infringements of intellectual property rights
or other rights of third parties.

Ð­Ð»ÐµÐºÑ‚Ñ€Ð¾Ð½Ð½Ñ‹Ð¹ ÐºÐ¾Ð¼Ð¿Ð¾Ð½ÐµÐ½Ñ‚: LA1838

ÐÐ»ÐµÐºÑ‚Ñ€Ð¾Ð½Ð½Ñ‹Ð¹ ÐºÐ¾Ð¼Ð¿Ð¾Ð½ÐµÐ½Ñ‚: LA1838