GENERAL DESCRIPTION

The SAA5700 is a Chinese teletext decoder suitable for TV and multimedia applications. It incorporates all the data slicing, acquisition and display circuitry on-chip, as well as the logic for memory management. An external DRAM is used to store the currently displayed page and also the precaptured teletext pages.

FEATURES

• Acquisition and display of the 625-line PAL CCST Chinese standard for teletext, with Chinese and Latin character sets

• Supports multiple DRAM sizes: 256K × 4 bits, 1M × 4 bits, 4M × 4 bits and 2 × 1M × 4 bits with an additional decoder/demultiplexer IC

• Acquires and stores in background up to (typically) 400 pages with 1M × 4 bits external DRAM

• CCST Fastext, with capability of displaying Chinese characters on Fastext prompt row

• Meshing for reduced contrast video background in subtitles and boxes

• Full line and screen colour to all edges of screen

• Supports 625-line 50/100 Hz display modes

• Scan-locked and stand-alone sync modes; supports video-locked sync modes with external PLL

• Easy control via high level I2C-bus SAFARI commands

• Sync mode switching and picture centring via I2C-bus SAFARI commands

• Supports external decryption unit for encrypted data.