UX-M55
1-31
18
19
20
21
22
23
24
25
26
27
28
29
30
SEB
VRO
RFRP
BTC
RFCT
PKC
RFRPIN
RFGO
GVSW
AGCIN
RFO
GND
RFN2
RFRP output circuit switching terminal
SEL level Bottom detection Peak detection
GND ON ON
Vcc OFF ON
Reference signal (VRO) output terminal
Track count signal output terminal
Time constant adjustment terminal for bottom detection
RFRP signal center level output terminal
Time constant adjustment terminal for peak detection
Input terminal for track count signal output amplifier
Output terminal for RF signal amplitude adjustment amplifier
Amplifier (AGC, FE, TE) gain switching terminal
GVSW Mode
GND CD-RW
Hiz Normal
Vcc Normal
Input terminal for RF signal amplitude adjustment amplifier
Output terminal RF signal amplifier
Ground terminal
Input terminal for RF signal amplifier
I
O
O
I
O
I
I
O
I
I
O
-
I
Pin No.
Symbol
I/O
Function
1 2 3
1. Terminal layout
NJM7812A (IC302) : Regulator
1.INPUT
2.OUTPUT (+12V)
3.GND
2. Block diagram
BANDGAP REFERENCE
1
INPUT
THERMAL SHUTDOWN
OVER VOLTAGE PROTECTION
SOA PROTECTION
SHORT CIRCUIT
PROTECTION
3
GND
2 OUTPUT
R1
R2
Q1