Sharp CD-CH1500 Service Manual page 42

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