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.