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4. Spindle Circuit
4-1-1. Block Diagram(FGCAV Servo)
43
Disc
Motor unit
Optical
Pick-up
HOP-8541T
XCO
Control Clock
Generator
IC301
R8J32005FP
255
M
U
X
P
W
M
SPD
88
Motor Kick
REG
CAV FD
+
CAV PD
SFG
VCK4M
VCK4M
254
R330
C319
R329
1.65V
SPD
IC601
M63041AFP
U
V
CTL1
CTL2
DAVC
1.65
1
20
21
12
13
19
42
SPD
SFG
CTL2
CTL1
SPIN
FG
W
14
XCL
86
R326
3.3V
X301
33.8688MHz
4-1-2. FG CAV Servo
1) CD 40x CAV : CD-RW, CD-R, CD-ROM
2) DVD 8x CAV : DVD+RW, DVD-ROM dual
3) DVD 10x CAV : DVD+R
4) DVD 16x 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(M63041AFP 19pin) input to SFG in DSP IC(IC301 86pin).
The spindle controller in DSP IC uses SFG 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 SPD(IC301 88pin) input to SPIN in Drive IC(M63041AFP 1pin)
after Low-Pass Filtering.
The PWM output signal U, V, W signal(M63041AFP 12, 13, 14pin) drives Spindle Motor without using a sensor,
and FG pulse output is generated as 18 pulses/rotation.