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4. Spindle Circuit
4-1-1. Block Diagram(FGCAV Servo)
46
Disc
Motor unit
Optical
Pick-up
HOP-8511T
XTALO
Control Clock
Generator
IC701
HD62604
127
M
U
X
P
W
M
DMO
20
Motor Kick
REG
CAV FD
+
CAV PD
SFG
VCK4M
VCK4M
126
R610
C606
SPIN
IC601
BD7905
U
V
MUTE2
MUTE1
VC
1.65
24
22
23
9
11
HU+
2
HU-
21
C601
HV+
HV-
3
4
HW+
HW-
5
6
1
27
SPIN
SFG
CTL2
CTL1
C602
C603
SPIN
FG
W
18
XTALI
17
R854
3.3V
X702
33.8688MHz
4-1-2. FG CAV Servo
1) CD 24x CAV : CD-RW
2) CD 32x CAV : CD-R, CD-ROM
3) DVD 8x CAV : DVD+RW, DVD+R, DVD-ROM dual
4) DVD 12x CAV : DVD-ROM(single)
When drive read PRESS CD, Closed Session CD-R/RW, the spindle motor is controlled using FG CAV Spindle
Servo. FG signal(BD7905 21pin) input to FGIN in DSP IC(IC701 17pin).
The spindle controller in DSP IC uses FGIN as spindle rotation frequency feedback, therefore the FG CAV
Spindle Servo doesn't work well if FG generation is abnormal.
The spindle controller PWM output signal DMO(IC701 20pin) input to SPIN in Drive IC(BD7905 24pin)
after Low-Pass Filtering.
The PWM output signal U, V, W signal(BD7905 9,11,18) drives Spindle Motor using Hall Sensor Output signal
(HU+, HU-, HV+, HV-, HW+, HW-) and SPIN, and FG pulse output is generated as 18 pulses/rotation.