Service manual
CD-CH1500
– 42 –
IC6 VHiTA2147F/-1: Servo Pre Amp. (TA2147F)
1 VCC — 3.3V power supply terminal
2 FNI Input Main beam amp input terminal
3 FPI Input Main beam amp input terminal
4 TPI Input Sub-beam amp input terminal
5 TNI Input Sub-beam amp input terminal
6 MDI Input Monitor photodiode amplifier input terminal
7 LDO Output Laser diode amp output terminal
8 SEL Input APC circuit ON/OFF signal, LDO terminal control input terminal and bottom/peak
detection frequency switching terminal
9 TEB Input Tracking error balance adjustment signal input terminal
• TEBC input voltage
10 TEN Input Tracking error signal generation amp antiphase input terminal
11 TEO Output Tracking error signal generation amp output terminal
12 SBAD Output RF signal peak detection output terminal
13 GVSW Input AGC, FE, TE amp gain switching terminal
14 VRO Output Reference voltage (VRO) output terminal • VCC=3.3V: VRO=1/2 VCC
15 FEO Output Focus error signal generation amp output terminal
16 FEN Input Focus error signal generation amp antiphase input terminal
17 RFRP Output Signal generation amp output terminal for track count
18 RFIS Input Signal generation amp input terminal for track count
19 RFGO Output RF signal amplitude adjustment amp output terminal
20 RFGC Input RF amplitude adjustment control signal input terminal • RFGC input voltage
21 AGCI Input RF signal amplitude adjustment amp input terminal
22 RFO Output RF signal generation amp output terminal
23 RFN Input RF signal generation amp input terminal
24 GND — GND terminal
Terminal Name
Pin No.
Input/Output
Function
GND OFF Connection to VCC via 1kΩ
Hi-z ON Control signal output
VCC ON Control signal output
SEL
APC circuit
LDO
GND CD-RW
Hi-z CD-DA
VCC CD-CA
GVSW Mode
Figure 42 BLOCK DIAGRAM OF IC
PIN
SEL
(APC_SW)
TEB
(TE_BAL)
RFGC
(AGC_Gain)
GVSW
(CD/RW)
V
CTRL
V
CC
HiZ
GND
APC ON
APC ON
APC OFF
(LDO=H)
-50%
0%
+50%
+12dB
+6dB
0dB
DA
(0dB)
DA
(0dB)
RW
(+12dB)
GVSW
VRO
FEO
FEN
RFRP
20K
20K
20K
15K
15K
10p
50u
20µ
12K
20K
20K
20K
2K
40K
50K
50K
40K
10p
1.3V
1K
14K
2K
SBAD
TEO
TEN
TEB
SEL
LDO
MDI
TNI
TPI
FPI
FNI
VCC
80K
80K
20K
20K
240K
15p
240K
15p
180K
40p
40p
60k
60k
180K
40K
20K
30K
3K
20K
12K
RFGC
AGCI
RFO
RFN
GND
RFIS
RFGO
3K
1
2
3
4
56
78
9
10
11
12
13 14 15
16
17
18
19 20 21 22
23
24
BOTTOM
PEAK
PEAK
K
x0.5
x2
x2
x0.5
1