ViewSonic N3735w-2M, Руководство по обслуживанию

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Flexible scalers provide wide adoption to various LCD panels for two of different video
sources at the same time. MT538x supports alpha blending for Video and two OSD planes. It
also supports 10bit gamma correction and advanced dithering processing for LCD display with
6/8/10 bit output.
C.
DTV and HDMI.
MT538x is a fully integrated single-chip 8-VSB and 64/256-QAM demodulator. The chip is
designed specifically for the digital terrestrial HDTV and CATV receivers. MT538x includes a
10-bit A/D converter, 8-VSB/QAM demodulator, TCM (Trellis-Coded modulation) decoder,
and Reed- Solomon Forward Error Correction decoder. Moreover, an internal controller
handles the acquisition and tracking to ensure the best receiving performance.
The internal controller communicates with the external host controller via the I2C-compatible
interface, and also provides direct control to the RF tuner via the second I2C-compatible
interface.
MT538x accepts either the direct IF signals and the IF signals are sampled by a 10-bit A/D
converter. Afterward, the digitized samples are further processed for adjacent channel
interference rejection. MT538x measures the power level of the digitized sequence, and feeds
the control voltages back to the RF tuner and the IF amplifier respectively. The control
voltages are converted to analog signals through the on-chip 1-bit sigma-delta D/A converters
plus the off-chip R-C low-pass filters. The automatic gain control keeps the received power
level at a desired level and maximizes the received SNR.
The MT538x includes a DTV Backend Decoder SOC which support flexible transport demux,
HD MPEG-2 video decoder, JPEG decoder, MPEG1,2, MP3, AC3 audio decoder.
It incorporates a processor for system control. The processor issues instructions to control the
peripheral via I²C. DDR
SDRAM is externally connected to the MT538x, the unified memory
allows all internal decoders can share data, which reduces external memory types and
capacities.
ViewSonic Corporation
Confidential - Do Not Copy
N
3735
w-
2M
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