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1.1.4 TE Generating Circuit
Tracking Error (TE) Generating Circuit
A
For DVD, using a phase difference method, TE is generated based on a phase difference between (A+C) and (B+D).
For CD, using a three beam method, TE is generated based on the equation TE = (F+H_G+H) - (E+G_E+F) after going
into the variable amplifier and AD converted.
DVD (TE based on phase difference)
CN1101
VIN4RF
B
17
A
99
0.1uF
VIN3RF
16
B
100
0.1uF
VIN2RF
18
C
98
0.1uF
19
VIN1RF
D
97
0.1uF
C
CD(TE based on the three-beam method)
CN1101
Input AMP
F+H_G+H
10
F+H_G+H
112
Gain switching
-6dB, 0dB, 9.5dB
E+G_E+F
11
E+G_E+F
111
D
After 10 bit ADC
F+H_G+H
Offset Cancel
E+G_E+F
E
F
4
1
2
LPF
Input AMP
Buffer gain
gain switching
switching
G=0,3,6,9,12,15dB
-6dB, 0dB, 3.5dB
LPF
11.3M
1MHz/2.5MHz/through
/5.7M Hz
LPF
11.3M
1MHz/2.5MHz/through
/5.7M Hz
LPF
11.3M
1MHz/2.5MHz/through
/5.7M Hz
LPF
11.3M
1MHz/2.5MHz/through
/5.7M Hz
MN2DS0018MA LSI
Selector
LPF
Buffer
LPF
50k Hz
G=0dB
Selector
LPF
50k Hz
MN2DS0018MA LSI
TE signal generating circuit
1+Ptbal0,1/0x0100
AMP
+
Tbal adjustment value
-
1-Ptbal0,1/0x0100
MN2DS0018MA LSI
2
3
HPF
Binary comparator
CMP
HPF
DAC
DAC
control filter
CMP
HPF
DAC
DAC
control filter
CMP
HPF
DAC
DAC
control filter
CMP
HPF
DAC
DAC
control filter
Buffer AMP
AMP
ADC
ADC
Gain switching
Gain switching
3dB, 9dB
6/7.5/9/10.5 dB
TE
CX-3283
3
4
TE signal generating circuit
Phase comparator
LPF (integrator)
AMP
Phase
D
comparator
+
+
4
TE
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