GL OBAL AND SCAL ABLE AR CHITECTURE

The TL855 is an integrated MPEG-2 MP@HL 4:2:2 video decoder, display processor and graphics accelerator for professional

supports direct video output to a variety of display types. It performs professional quality decoding (4:2:2) of a single HD program

(MP@HL). An integrated graphics accelerator renders text and graphics to an independent on-screen display (OSD) bitmap.

The IC buffers the audio data, allowing the use of a standard Dolby Digital (AC-3) decoder chip or software on a host CPU for

audio decoding.

The TL855 accepts MPEG compressed data encoded in the 4:2:2 format. Four Y, two Cb and two Cr values are generated for

every four pixels decoded. Compared to 4:2:0 decoding, 4:2:2 decoding generates two extra chroma components requiring a

considerable increase in performance over 4:2:0 consumer decoders. Therefore

the TL855 memory interface, the MPEG decoder core engine and the display

controller must be highly tuned for 4:2:2 processing. The memory interface has

twice the buffering of conventional 4:2:0 decoders to handle the extra amount of

chroma component during writes and reads. The MPEG decoder engine decodes

the extra chroma values. The display controller accepts 4:2:2 data from the SDRAM

as decoded by the MPEG decoder engine, then displays this higher quality video

on the screen.

The TL855 is able to process all ATSC, DVB-HD and ARIB formats (and other

worldwide and proprietary decoding such as DIRECTV) in high quality 4:2:2 video

and then display the resultant video at this quality. In addition to the MPEG-2 4:2:2 decode, the TL850 performs format conversion

from any ATSC format to any other ATSC format (including many non-standard resolutions). An on-chip 2D graphics accelerator

provides TV-centric graphics and OSD to complement the video quality. A PCI interface allows ease of interfacing to a variety of

common off-the-shelf components suitable for professional systems. In addition to these functions the TL855 can be programmed

into a 4:2:0 mode of operation.

All Format video/graphics solution for studio or professional quality equipment

TL855

Professional Digital TV Decoder

5.1

Channel

5.1

Channel

MPEG Transport Data

QPSK, QAM or

VSB Receiver

PCI Bus

32

64

8

16MB - 64MB

SDRAM

TL855

RGB or

YPbPr

and Sync

I2S

Digital RF

Studio Source

Audio Decoder

HDTV

Audio DACs

!

IEC958

TL855 SYSTEM DIAGRAM

TERA3359.SellSheets.ICs

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