ROHM BU9312AKS

Optical disc ICs
Servo signal processor for CD
BU9312AKS
The BU9312AKS is a CD servo signal processing IC that contains a speed doubling unadjusted PLL, program servo,
and signal processor, and that delivers low voltage operation and low power consumption. This IC is ideal for miniaturized, low-power-consumption applications.
FApplications
Portable CD players, portable stereos and mini component stereo systems
FFeatures
1) Internal PLL circuit, allowing EFM data demodulation
and bit clock sampling with minimum attached components.
2) Frame synch signal detection and protection.
3) Internal focus, tracking and thread servo filters.
Characteristics can be controlled with commands
from the controller.
4) Subcode serial output pin.
5) Output pins for P code and Q code.
6) Internal CLV sequencer that automatically sets the
CLV mode.
7) Internal track jump sequencer that jumps the desired number of tracks.
8) Single-chip IC with deinterleaving function and internal C1 / C2 double error detection, correction
and flag processor.
9) Signals to DAC are output via MSB fast 2’SCOMP
serial outputs, enabling control of ON / OFF operation of CD-ROM interpolators.
10) 16k bits of internal SRAM, for the storage of up to
± 4 frames of jitters.
11) Doubled-speed playback.
79
Optical disc ICs
FAbsolute maximum ratings (Ta = 25_C)
FRecommended operating conditions (Ta = 25_C)
FBlock diagram
80
BU9312AKS
Optical disc ICs
BU9312AKS
FPin description
81
Optical disc ICs
82
BU9312AKS
Optical disc ICs
BU9312AKS
FInput / output circuits
FElectrical characteristics (unless otherwise noted, Ta = 25_C, VDD = 5V)
83
Optical disc ICs
FExternal dimensions (Units: mm)
84
BU9312AKS