VESTEL 17MB45-2, Руководство по обслуживанию

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36
Pin Configuration
11.13 XC5000 (Optional)
XC50000 is a RF to Baseband Silicon Tuner and the usage of XC5000 is optional on
MB45TV set.
General Description
The Single-Chip Multi-Standard Tuner + VIF/SIF XC5000 supports all analog TV formats
transmitted worldwide in the 42-864 MHz band on either cable or terrestrial broadcast
channels. It implements on-chip tuning, channel filtering and demodulation, without external
(SAW) filters and has no manually tunable parts. The broadband tuner converts the selected
channel into an Intermediate Frequency (IF), which is then sampled by an internal high-
resolution analog-to-digital converter (A/D) for further processing. For analog broadcast
standards the video signal is demodulated and output as a composite video base-band signal
(CVBS) through a high-performance smoothing filter. The sound carrier is filtered and output
as a 2nd Sound IF (SIF) or demodulated and output as a mono TV sound. In DTV mode, the
Digital TV signals are filtered using a standard-dependent high-rejection channel fitler and
converted to a user-programmable output frequency. At the output of the D/A converter, the
DTV signal is low-pass filtered using a high-performance smoothing filter and input to a
variable gain amplifier. The amplifier gain can be controlled via an external analog signal on
Vagc.
Features
_ Standard specific digital picture carrier recovery:
Alignment-free
Quartz-stable and accurate
No externally tunable parts
_ Multi-standard RF-to-baseband receiver
_ Integrated RF PLL filter reducing risk of noise pickup on the board
_ Standard specific digital video/audio splitting
_ Integrated DSP for high quality demodulation both in analog and digital modes
_ Integrated smoothing filters for CVBS output (analog mode) and IF-output (digital mode)
_ Supports DDI (digital direct interface) interfacing to the digital demodulator equipped with
DDI, eliminating the quantization noise (from DAC/ADC).
_ Onboard digital processing for the following analog standards: B/G, D/K, I, L/L’ and M/N
_ Inter-carrier sound output or mono analog sound direct output