Hitachi CL2554AN, Руководство по обслуживанию

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Service manual CL2554AN / CL2854AN
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4-2 MSP3415D Multistandard Sound Processor
The MSP 3415D is designed as a single-chip Multistandard Sound Processor for applications
in analogue and digital TV sets, video recorders, and PC cards.
MSP 3415D features
- sound IF input
- No external filters required
- Stereo baseband input via integrated AD converters
- Two pairs of DA converters
- Two carrier FM or NICAM processing
- AVC : Automatic Volume Correction
- Bass, treble, volume processing
- Full SCART in/out matrix without restrictions
- Improved FM-identification
- Demodulator short programming
- Auto-detection for terrestrial TV - sound standards
- Precise bit-error rate indication
- Automatic switching from NICAM to FM/AM or vice versa
- Improved NICAM synchronisation algorithm
- Improved carrier mute algorithm
- Improved AM-demodulation
- Reduction of necessary controlling
- Less external components
Basic Features of the MSP 3415D
Demodulator and NICAM Decoder Section
The MSP 3415D is designed to simultaneously perform digital demodulation and decoding of
NICAM-coded TV stereo sound, as well as demodulation of FM or AM mono TV sound.
Alternatively, two carrier FM systems according to the German terrestrial specs can be
processed with the MSP 3415D.
The MSP 3415D facilitates profitable multistandard capability, offering the following
advantages:
- Automatic Gain Control (AGC) for analogue input: input range: 0.10 - 3 Vpp
- integrated A/D converter for sound-IF input
- all demodulation and filtering is performed on chip and is individually programmable
- easy realisation of all digital NICAM standards (B/G, I, L and D/K)
- FM-demodulation of all terrestrial standards (include identification decoding)
- no external filter hardware is required
- only one crystal clock (18.432 MHz) is necessary
- high deviation FM-mono mode (max. deviation: approx. ±360 kHz)
DSP-Section (Audio Baseband Processing)
- flexible selection of audio sources to be processed
- performance of terrestrial de-emphasise systems (FM, NICAM)
- digitally performed FM-identification decoding and de-matrixing
- digital baseband processing: volume, bass, treble