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1.4 Power Supply Loading Unit
This system power supply uses VD (8.3±0.5 V) supplied
from the mother substrate. The VD supply destination
is a 5-ch CD driver IC or 5 V regulator IC. The power
supply used inside the system is the two systems of the
above VD (drive system), and V+5 (control system).
The ON/OFF other than the loading and ejection of the
CD driver is controlled by the microcomputer with
"CONT" and the 5V ON/OFF is controlled by the
microcomputer with "CD5VON", respectively. For the
ON/OFF of the loading drive, no control terminal is
provided in particular, but input signal "CDEJET" or
"CDLOAD" functions in the same way.
CN701
32
31
PGND
30
29
28
GND
27
26
3
24
AGND
23
IC801
BA05SFP
CD5VON 13
1
4
2
CONT 20
CDEJET 11
CDLOAD 10
8
VD
7
6
DSCSNS 21
S903
S902
Fig.22:POWER SUPPLY / LOADING SYSTEM CIRCUIT BLOCK
The loading or ejection operation is controlled
according to the state changes of the clamp switch on
the mechanical unit and the three switches on the
control unit. The DSCSNS voltage changes according
to the ON/OFF states of these switches. For this
voltage, each of states (A to E) is judged using the
microcomputer A/D port. An eight/12 cm disk is judged
according to this state transition. Fig. 23 shows each
status and Fig. 24 shows the state transition.
DETECTION SWITCH STATUS AT THE TIME OF LOAD EJECTION
STATUS
A
SW1(S901)
ON
SW2(S902)
OFF
SW3(S903)
OFF
SW4(CLAMP SW)
OFF
MECH. STATUS
NO DISK
Fig.23:DSCSNS STATUS
IC401
BA5811FM
GND
19
LOP
10
MUTE
V+5
21
LOADING
M
REV
MOTOR
2
FWD
1
9
LOM
7
8
PREVCC
VCC
CLAMP SW
S901
Mechanism Unit
B
C
D
OFF
OFF
OFF
OFF
ON
ON
OFF
OFF
ON
OFF
OFF
OFF
E
ON
OFF
OFF
ON
CLAMP
CX-961
13
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