Pioneer deh-p980bt Service Manual page 126

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1.1.2 RF and RFAGC amplifiers
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The output from the photo-detector (A + C) and (B + D) is provided from the RFO terminal as the RF signal (which can be
used for eye-pattern check), after it is added, amplified, and equalized inside this LSI. The low frequency component of
the voltage RFO is calculated as below.
RFO = (A + B + C + D) x 2
The RFO is used for the FOK generation circuit and RF offset adjustment circuit.
The RFO signal, output from the pin 119, is A/C-coupled externally, input to the pin 118, and amplified in the RFAGC
amplifier to obtain the RFAGC signal.
Also, this LSI is equipped with the RFAGC auto-adjustment function, explained below, which switches feedback gains of
the RFAGC amplifier so that the RFO output will be 1.5 V.
This RFO signal is also used for the EFM, DFCT, MIRR, and RFAGC auto-adjustment circuits.
Pickup Unit
P3
P7
P9
VREF
TE
L 13942296513
P2
P4
P8
Fig.1.1.2 RF/AGC/FE
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CD CORE UNIT
UPD63763CGJ
VREF
A+C
A
13
13
124
10k
C
125
10k
B+C
D
6
6
127
10k
B
126
10k
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2 9
8
+
-
15.2k
15.2k
35k
RFOFF setup
R2
+
61.0k
-
+
-
Q Q
8.8k
3 6 7 1 3 1 5
111k
+ 61.0k
-
8.8k
co
.
CX-3164
7
9 4 2 8
RF-
RF2-
EQ2
10k 10k
EQ1
7.05k
+
-
-
+
AGCO
20k 11.2k
To DEFECT/A3T detection
For RFOK generation
+
FEO
-
0 5 8 2 9 9 4
FE A/D
FE-
FEOFF setup
VREF
m
7
8
9 9
A
B
123
4.7k
122
22p
1.2k
120
4p
56p
1.2k
121
5.6k
116
C
136
2 8 9 9
135
D
E
F
5
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