Overview The LC895297 is a single-chip CD-ROM decoder and CD-DSP system that supports full CAV 20× operation and includes a built-in ATA-PI (IDE) interface. Features [CD-ROM Decoder and ATA-PI (IDE) Interface Blocks] • Full CAV 20× operation • ATA-PI (IDE) interface • Supports the use of EDO DRAM. • Supports the use of up to 4 Mbits of buffer RAM. • The user can set up arbitrary CD main channel and C2 flag areas in buffer RAM. • Batch transfer function (function that automatically transfers the CD main channel and C2 flag data in a single operation.) • Multi-block transfer function (function that automatically transfers multiple blocks in a single operation.) • DVD ECC interface • Intelligent functions [CD-DSP Block] • The IC inputs a high-frequency signal, slices that signal at the correct level, converts that result to an EFM coded signal, and compares the phase with that of the built-in VCO. • Uses an external 16.9344-MHz crystal element to generate a standard clock and to correctly generate the required internal timings. • Performs frame synchronization, signal detection, protection, and insertion, and assures stable data readout. • Demodulates the EFM coded signal to produce 8-bit symbol data. • After applying a CRC check to the subcode Q signal, outputs that signal to a microprocessor over a parallel I/O channel. • Performs unscrambling and de-interleaving to reorder the demodulated EFM signal in the prescribed manner. • Performs error code detection and correction, and flag processing. (C1: dual errors, C2: four errors) • Sets the C2 flags based on the C1 flags and a C2 check, and performs interpolation or muting depending on the C2 flags. Adopts a 2-point interpolation circuit, and converges the signal to the muting level if the C2 flags indicate over 2 consecutive uncorrectable errors. • Accepts the input of commands from a control microprocessor over an 8-bit parallel interface. Supports track jump, disc motor start/stop, muting on/off, and track counting commands. • Can perform arbitrary track counts. • Includes CAV audio functions. • Adopts zero-cross muting. • Includes 8× oversampling digital filters. • D/A converter with PWM output. • Includes independent left and right channel digital attenuators. • Provides digital deemphasis. • Supports bilingual functions.
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