Panasonic PT-53TWD63, Technical Manual

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The tuner of the DT-Board outputs a 44MHz IF (Intermediate Frequency) sig
which is in digital form. The IF signal is then applied to a transport decoder circu
consisting of IC8008 to recover the Transport Stream. The MPEGII transport
stream then enters the input selection IC, IC8009. The 8VSB or 16 VSB
transport stream passes through the switch and enters IC8024. If a CableCard is
used, the 16VSB TS signal enters the CableCard for decoding and channel
mapping. Once the unit senses the presence of the CableCard, it automatically
instructs IC8009 to switch its output to the CableCard.
nal
it
n vectors. Video fields or frames are assembled and stored in
The Dolby Digital audio decoder circuit de-packetizes the data. Dolby Digital
provides five discrete full-bandwidth channels for front left, front right, center,
surround left and surround right, plus a LFE (Low Frequency Effect) subwoofer
channel. For a full Home Theater sound experience, an external
Dolby Digital decoder and a multi-channel amplifier must be connected to the
Digital Audio Out jack on the PTV.
Note:
When an ATSC channel is selected, the output from the Digital Audio Out
jack will be Dolby Digital. But, if NTSC channel is selected, the output will be
LPCM.
All TV related OSD information is generated by IC8024. Channel numbers,
program channels, etc are generated within this IC.
IC8024 is used as temporary storage location for the process of de-packetizing
the AC3 audio.
IC8018 contains the algorithmic (firmware) information for the operation of the
digital tuner. Due to possible changes that may come up as the OpenCable
service matures, the firmware information located in IC8018 may be upgraded by
using an SD card.
IC8015 contains the host identificatio
r and stores the POD identification
ts
al
The transport Stream enters the video decoder IC8024. When receiving the data
packets from the transport decoder, the video decoder de-packetizes the data,
nd extracts motio a
memory circuits, IC8020 and IC8021, and output as digital component-signals.
n numbe
number of the cable service provider.
IC8032 (See Figure 29) is used for analog audio inputs. All analog audio inpu
are converted to digital and entered into IC8024 for conversion into LPCM. The
digital audio is output via the Optical Audio Out jack for use with a Dolby Digit
decoder and a multi-channel amplifier.
Note:
The unit may also be operated without the DT board installed.
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