Description

The CXD2598Q is a digital signal processor LSI for CD players. This LSI incorporates a digital servo, digital filter, 1-bit DAC and analog low-pass filter on a single chip.

Features

• All digital signal processing during playback is performed with a single chip

• Highly integrated mounting possible due to a built in RAM



Digital Signal Processor (DSP) Block

• Playback mode supporting CAV (Constant Angular Velocity)

  • Frame jitter free

  • 0.5×to 4×continuous playback possible

  • Allows relative rotational velocity readout

• Wide capture range playback mode

  • Spindle rotational velocity following method

  • Supports normal-speed to 4×speed playback

• Supports variable pitch playback

• The bit clock, which strobes the EFM signal, is generated by the digital PLL.

• EFM data demodulation

• Enhanced EFM frame sync signal protection

• Refined super strategy-based powerful error correction

  C1: double correction, C2: quadruple correction

  Supported during 4×speed playback

• Noise reduction during track jumps

• Auto zero-cross mute

• Subcode demodulation and Sub-Q data error detection

• Digital spindle servo

• 16-bit traverse counter

• Asymmetry correction circuit

• CPU interface on serial bus

• Error correction monitor signal, etc. output from a new CPU interface

• Servo auto sequencer

• Fine search performs track jumps with high accuracy

• Digital audio interface outputs

• Digital level meter, peak meter

• Bilingual compatible

• VCO control mode

• CD TEXT data demodulation



Digital Servo (DSSP) Block

• Microcomputer software-based flexible servo control

• Offset cancel function for servo error signal

• Auto gain control function for servo loop

• E:F balance, focus bias adjustment functions

• Surf jump function supporting micro two-axis

• Tracking filter: 6 stages

  Focus filter: 5 stages



Digital Filter, DAC and Analog Low-Pass Filter Blocks

• DBB (digital bass boost) function

• Digital de-emphasis

• Digital attenuation

• 8fs oversampling digital filter

• Adoption of tertiary ∆∑noise shaper

• S/N: 100dB or more (master clock: 384Fs, typ.)

  Logical value: 109dB

• THD + N: 0.007% or less (master clock: 384Fs, typ.)

• Rejection band attenuation: –60dB or less

• Double-speed playback supported



Applications

CD players