Polaroid PLA-4200M, Руководство по обслуживанию

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PDP TV SERVICE MANUAL
(2) MSP3450G
Multistandard Sound Processor Family
Release Note: Revision bars indicate significant changes to the previous edition. The hardware and software
description in this document is valid for the MSP 3450G version B5 and following versions.
Introduction
The MSP 3450G family of single-chip Multistandard Sound Processors covers the sound processing of all analog
TV-Standards worldwide, as well as the NICAM digital sound standards. The full TV sound processing, starting with
analog sound IF signal-in, down to processed analog AF-out, is performed on a single chip. Figure4 shows a
simplified functional block diagram of the MSP 3450G.
This new generation of TV sound processing ICs now includes versions for processing the multichannel television
sound (MTS) signal conforming to the standard recommended by the Broadcast Television Systems Committee
(BTSC). The DBX noise reduction, or alternatively, MICRONAS Noise Reduction (MNR) is performed alignment
free.
Other processed standards are the Japanese FM-FM multiplex standard (EIA-J) and the FM Stereo Radio standard.
Current ICs have to perform adjustment procedures in order to achieve good stereo separation for BTSC and EIA-J.
The MSP 3450G has optimum stereo performance without any adjustments.
All MSP 3450G versions are pin and software downward-compatible to the MSP 3450D. The MSP 34x0G further
simplifies controlling software. Standard selection requires a single I
2
C transmission only.
The MSP 34x0G has built-in automatic functions: The IC is able to detect the actual sound standard automatically
(Automatic Standard Detection). Furthermore, pilot levels and identification signals can be evaluated internally with
subsequent switching between mono/ stereo/bilingual; no I
2
C interaction is necessary (Automatic Sound Selection).
The ICs are produced in submicron CMOS technology. The MSP 34x0G is available in the following packages:
PLCC68, PSDIP64, PSDIP52, PQFP80, and PLQFP64.
Fig. 4: Simplified functional block diagram of the MSP 3450G
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