Toshiba 21E88, Service Manual

Page: 52 / 68

SERVICE MANUAL
6. MSP34X0G
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 MSP34X0G version B5 and following
versions.
1). Introduction
The MSP34X0G 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. Figure 10 shows a
simplified functional block diagram of the
MSP34X0G.
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 MSP34X0G has optimum stereo
performance without any adjustments.
All MSP34X0G versions are pin and
software downward-compatible to the
MSP34X0G. The MSP34X0G further simplifies
controlling software. Standard selection
requires a single I
2
C transmission only.
The MSP34X0G 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 MSP34X0G is available in the following
packages, PLCC68, PSDIP64, PSDIP52,
PQFP80 and PLQFP64.
2). Block Diagram
Fig. 23 Simplified Functional Block Diagram of the MSP34X0G
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