LG GSA-4167B - Manual (Page 49)

4. Spindle Circuit
4-1-1. Block Diagram(FGCAV Servo)
53
Disc
Motor unit
Optical
Pick-up
HOP-7632TS
XCO
Control Clock
Generator
IC301
R8J32007
107
M
U
X
P
W
M
SPD
211
Motor Kick
REG
CAV FD
+
CAV PD
SFG
VCK4M
VCK4M
106
R349
C349
R375
1.65V
SPD
IC601
R2S30202FP
U
V
CTL1
CTL2
DAVC
1.65
1
20
21
12
13
19
42
SPD
SFG
CTL2
CTL1
SPIN
FG
W 14
XCI
213
R361
3.3V
X301
33.8688MHz
4-1-2. FG CAV Servo
1) CD 48x CAV : CD-ROM, CD-R
2) CD 40x CAV : CD-RW
3) DVD 8x CAV : DVD+RW
4) DVD 10x CAV : DVD+R
5) DVD 12x CAV : DVD-ROM DL
6) DVD 16x CAV : DVD-ROM
7) DVD 16x PCAV : DVD+R
When drive read PRESS CD, Closed Session CD-R/RW, the spindle motor is controlled using FG CAV Spindle
Servo. FG signal(R2S30202FP 19pin) input to SFG in DSP IC(R8J32007 213pin).
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(R8J32007 211pin) input to SPIN in Drive IC(R2S30202FP 1pin)
after Low-Pass Filtering.
The PWM output signal U, V, W signal(R2S30202FP 12, 13, 14pin) drives Spindle Motor without using a
sensor, and FG pulse output is generated as 18 pulses/rotation.