Sharp DV-500D Technical Manual page 23

4. How to Make Spindle Error Signal
Due to CLV control, error signals come from the reproduction signal.
DVD: approx. 580rpm ~ 1400rpm CD: 200rpm ~ 460rpm
A A
B
B
+
C C
D D
Reproduction Signal
<Wave shape Image>
Reproduction Signal
(after 2 values)
VCO output
The VCO same wave number is low.
Increase it with the phase comparison error signal.
VCO output
X'tal output
The VCO same wave number is high.
Decelerate the spindle motor with the phase comparison error signal.
Amplifier AGC
Phase
Comparison
VCO
Phase
Comparison
X'tal
27MHZ
Then
The VCO same wave number is low.
Increase it with the phase
comparison error signal.
23
Asymmetrical
EQ
Revision
LPF
Error Signal
CLV Spindle Error Signal
LPF
Found the phase!
PLL lock
Locked
X'tal and VCO
(immediate 5 reproduction signals) locked.
After all, the disc is rotating
at the regulated line speed.
DVD-Series
PLL Signal
Spindle
Error Signal