Spindle Control - Sony DVP-M35 Operation Manual

3-2-3. Spindle Control
This section describes the flow of control signals in the spindle servo during DVD playback.
The CLV control signal is generated from the RF signal obtained from the optical pickup in
' IC806 (CXD1865) to generate the two servo error signals-disc CLV speed error (MDSO (_
P) and CLV phase error (MDPO (_)P).
These two error signals is added by IC301 (NJM3404) and output from OP.
The spindle error output signal SPERR of the OP of IC301 is input to the spindle drive IC
(IC303:LB 1896).
The IC303 is a 3-phase brushless motor drive IC, and it contains a spindle error signal
amplifying circuit, gain switching circuit, and motor forced acceleration and deceleration
control circuit.
Gain switching is done with the SPGC1 signal ((_)P).
Disc size (CD/DVD) SPGC1 level
12 cm H
8 cm L
At the start and stop of disc playing, the forced acceleration and deceleration control is
executed.
Control mode Input signals
SPCTRL0 ((_)P) SPCTRL 1 ((_)P)
Acceleration H L
Deceleration H H
No control L H
MB-78 board t
le806
CXD1865
ARP
IC301 NJM3404
MDPO , I-'_"___
IC303
LB1896
SPEER_
H' 12cm _:l
_I
' I I,-
,L:Scm , _1 ;_1
-- -- -- '-ol U_l
Gain switching
From
IC804
LGACXD8728
_1 TO spindle
• l motor
Figure 3-11. DVD spindle control
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