Bose Lifestyle CD5 Series I, Service Manual

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10
CD TERMS
Major Components of the System
ASP: Analog Signal Processor. The component in the CD circuitry that contains the RF ampli-
fier, VCO, and the tracking, focus, and sled servos.
DSP: Digital Signal Processor. The component in the CD circuitry that performs slicing, EFM
demodulation, CIRC decoding, error correction and concealment, track access, CLV regula-
tion, and drives the D/A.
Digital to Analog Converter (D/A, DAC): A device that converts digital information (usually a
serial data stream) into an analog signal.
µ
C: Micro Controller. The component of the CD circuitry that performs track access, se-
quences all events (such as focus, disc start, stop, etc.), monitors for servo errors, and pro-
cesses user information (commands, door open, etc.).
CLV Servo: The circuit that keeps the disc rotating at a constant linear velocity.
Focus Servo: The circuit that keeps the optical pickup’s lens the proper distance away from
the surface of the disc.
Sled Servo: The circuit that keeps the sled positioned within the linear range of the tracking
actuator.
Tracking Servo: The circuit that keeps the optical pickup’s lens positioned within a single track
as the disc rotates.
VCO: Voltage Controlled Oscillator. Part of the phased locked loop circuit that generates an
output frequency dependent on its input voltage.
Signal Names
ATSC: Anti-Shock Circuit.
SLEQ: Sled Equalizer
FDO: Focus Drive Output
FEAO: Focus Error Amplifier Output.
HFL: High Frequency Level
PDO: Phase Detector Output
PH: Peak Hold
SLDO: Sled Drive Output.
SPDO: Spindle Drive Output.