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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’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.
Monolithic Linear IC
Electronic Channel Select
System Control Circuit for TV/VCR Use
Ordering number:ENN2843
LA7938
SANYO Electric Co.,Ltd. Semiconductor Company
TOKYO OFFICE Tokyo Bldg., 1-10, 1 Chome, Ueno, Taito-ku, TOKYO, 110-8534 JAPAN
Overview
The SANYO LA7938 monolithic linear TV/VCR electronic
tuner system controller IC integrates all the peripheral circuitry for a TV or VTR tuner, with the exception of the
microcontroller, into a single chip.
It incorporates a 2-input/4-output band-switch, 5.0V and
5.75V voltage regulators, comparator, sync signal processing circuit, AFT DC shift circuit and constant current circuit. Each PNP output of the band-switch circuit typically
sources 40mA, eliminating the need for external current
drivers.
The LA7938 operates from a recommended supply voltage range of 8.7 to 12.5V. It is available in 22-pin shrink
DIPs.
Features
• Integrates all tuner peripheral circuits except controller.
• Band-switch outputs source up to 40mA.
• Regulators each supply up to 50mA.
• 22-pin shrink DIP.
Specifications
Maximum Ratings at Ta = 25˚C
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erutarepmetegarotSgtsT 051+ot55–
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V
1CC
egatlovtupnideilppA
egatlovylppusmumixamV
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81
I91xam 05–Am
I02xam 05–Am
I12xam 05–Am
I22xam 05–Am
V6xam 5.3V
V5xam 5.3V
Ta≤65˚C
xam 31V
Package Dimensions
unit:mm
3059-DIP22S
[LA7938]
22 12
6.4
7.62
111
0.95 0.48
21.2
1.78
3.25
3.9max
3.3
0.51min
1.7
SANYO : DIP22S
Continued on next page.
0.25
˚C
˚C
12501TN (KT)/N248YT, TS No.2843–1/4
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LA7938
Continued from preceding page.
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]tiucrictfihsTFA[
egatlovtupnimumixaMxam61VVCCV31=131V
* : The rating for the total current drawn from both the 5.0V and 5.75V supplies is 70mA.
Operating Conditions at Ta = 25˚C
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egnaregatlovgnitarepOV
xam 5.3V
1
xam 4.1– V
1
xamVCCV31=101V
3
xamVCCV=1
4
xam 31V
31
xam *05– Am
21
xam *05– Am
9
V8xamVCCV31=231V
V01xamVCCV31=231V
xam 6V
11
xam 34V
41
po 5.21ot7.8V
CC
V21=26.4V
CC
(Band Switch Truth Table)
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H
L
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B
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L
H
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Z
Operating Characteristics at Ta = 25˚C, V
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noitalugeregatlovtuptuo57.5+V
egatlovtuptuoV0.5+V
noitalugeregatlovtuptuoV0.5+V
CC
CC
F1).tas(IOAm04–= 7.0V
F2).tas(IOAm04–= 7.0V
F3).tas(IOAm04–= 7.0V
F4).tas(IOAm04–= 7.0V
V
V
V
OL5
V
OL6
LF
21
9
2F
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3F
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4F
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Z
Z
H
Z : HIGH-impedance
1, VCC2=12V
CC
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2 0.7Am
IH5
IH6
HT1
I
)tas(2
IH3
OH3
I
)tas(4
I
21
I
geR21
21
I
9
I9Am5= → Am0205001Vm
geR9
Am01=0.1V
KNIS
Am2=7.0V
KNIS
Am02–=53.557.551.6V
Am5= → Am0252– 52+Vm
Am02–=6.40.54.5V
.)pihcnoecnatsiserpu-llup(etats
FFOniebtsumretupmocorcimepytetagnepO
8.0V
8.0V
05– Aµ
4.027.05.1V
0.5V
0.3V
Continued on next page.
No.2843–2/4
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