BBK 9903S, Service Manual

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MT1379
PRELIMINARY, SUBJECT TO CHANGE WITHOUT NOTICE MTK CONFIDENTIAL, NO DISCLOSURE
F
UNCTIONAL
B
LOCK
S e r v o
D S P
S e r v o
I O
A n a l o g
F r o n t e n d
D P U
C h a n n e l
D e c o d e
M i c r o p h o n e
I n p u t
A u d i o
O u t p u t
A u d i o
P r o c e s s o r
D R A M
I n t e r f a c e
V i d e o
D e c o d e r
S y s t e m
P a r s e r
V i d e o
O u t p u t
P l a y b a c k
C o n t r o l l e r
S y s t e m
C o n t r o l l e r
C S S /
C P P M
D R A M F l a s h
I R /
V F D
D V D m o d u l e
D e b u g
P o r t
S P D I F
S p i n d l e
C o n t r o l l e r
T V e n c o d e r
A u d i o D A C
MIC
Servo Controller
The servo control is accomplished through the servo DSP (Servo Digital Signal Processor) and its accessory I/O circuits. This servo
DSP is capable of performing complex operations an d also provides a friendly interface for the system controller. By issuing type
1 and type 2 commands from the system controller, the servo DSP can accomplish various complicated servo control functions,
such as tracking, seeking and MT1336/MT1376 chip register programming. As for the servo I/O circuits, it provides interface
between the input servo signals and the Servo DSP. It has built-in ADCs to digitize the servo control signal and DACs to provide
signals for the actuator and sledge motor. It also has a serial interface to communicate with the MT1336/MT1376 chip.
Analog Front End
The analog front end contains a data slicer circuit and a data PLL circuit. The RF analog signal from MT1336/MT1376 is
quantized by the data slicer to form the EFM/EFM+ bit st ream, from which the channel bit clock is extracted by the data PLL.The
EFM/EFM+bit stream and bit clock are then output to DPU for channel bit processing.
DPU
Data path unit (DPU) provides protection on data with lost synchronization patterns and demodulates EFM/EFM+ bit stream into
the channel raw data that will be corrected by the decoder. The synchronization protection makes data after the synchronization
pattern to be extracted even if the synchronization pattern is not found.
Spindle Controller
The spindle controller is used to control disc spindle motor. It includes a varipitch CLV clock generator, a CLV/CAV controller,
and a PWM generator. The varipitch CLV clock enerator generates a reference colck for the speed of operation. The CLV/CAV