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5
EQUALIZER
b) Brake circuit
Since lead-in of servo is weakened during set-up or track
jump, stable lead-in to servo loop is performed, using a
brake circuit. The brake circuit detects the direction of a
lens and outputs only the drive signal of the cross
direction toward its operation to slow the lens speed down
and performs stable lead-in to the tracking servo. In
addition, the direction for sliding a track is determined by
TEC signal, MIRR signal and its phase relation.
TEC
TZC
(TEC becomes pulse)
(Internal signal)
MIRR
MIRR is latched
by the edge of
TZC pulse.
SWITCHING PULSE
EQUALIZER OUTPUT
(SWITCHED)
DRIVE DIRECTION
5
6
TEC
T.BRAKE
SERVO
SD
Fig.9-2 Multi-track jump(Speed control)
Lens moving forward
(from inner side to outer side)
REVERSE
(NOTES) The phase of equalizer output is written as the same as TEC phase.
Fig.10 Tracking brake circuit
CX-3168
6
7
50ms
Lens moving backward
FORWARD
Time
7
8
A
B
C
D
E
F
9
8
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