Philips DVD580M Service Manual page 52

EN 52 9. DVD580M
CS, CLK and DATA perform the communication between VFD
driver and CPU.
VFD driver also keep scanning the keyboard (front panel
buttons) periodically to detect the user command and transfer
to CPU for performing the action.
Remote Control Isolation Circuit And Cpu Interface At
Front Panel
To CPU on front Board
R313
10k OHM
IR
Figure 9-24 Remote Control Isolation
The two transistors in the circuit are used for isolation of remote
signal. Infrared signal for remote receiver will be send to the
CPU (front panel board) for command processing. When the
set is in standby condition, no voltage is supply to the Decoder
IC; the output voltage at IR receiver is in low output condition,
the CPU (front panel) will not receive the IR signal from remote
handset without the isolation circuit.
In the following diagram shows that a high stage voltage will be
send out from U302 to turn off all supply other than the VCC.
R323 R315 D305 R321 R322 R325
10K 10K 1N4148 10K 10K 10K
U302
1
RA2
STD 2
RA3
3
T0CKI
4
/MCLR
5
Vss
K301 6
RB0
PMUTE
POWER + 7
RB1
HPON
8
RB2
9
RB3
C311
10uF
Figure 9-25 U302 Control Diagram
Digital Audio Output Circuit
+5V L1
AXIAL
+
R161
C133 C134 1K
47uF/16v 0 1UF
R163
2 2K
R162 C135
68 OHM 104
SPDIF1
R167
330OHM
Figure 9-26 Digital Audio Out
Circuit description
VCC
R320
10K
R319
10K
IR1
Q302
9014C
Q301
9014C
CL 26532085_048.eps
190702
VCC
R316 R317 R324
4 7K 4 7K 4 7K
C315
104
18 IR
RA1
17 NOTE STDBY
RA0
16
OSC1
15
OSC2
14
Vdd
13 POWOFF
RB7
PCON
12
RB6
11
RB5
10 C314 C313
RB4
47P 22P
PIC1 6C54S
D304 R318
DOUBLE LED 4 7K
R314
470
CL 26532085_049.eps
Q13
9014C
C136 R165
104 330 OHM
L2
SHORT£ 1000 OHM£©
R164 R166
1K 91 OHM C137
OPEN£ 220P£©
CL 26532085_050.eps
Digital audios are source from the decoder (ESS60x8) chip set
that is the serial data stream in SPDIF format. There are two
form of digital audio output, one of them is coaxial, and while
the other one is optical. The optical terminal is an electrical to
optical signal converter.
9.9 Trouble Shooting On The Disc Loader Of
Dvd580m
The Disc loader in DVD580M is of Slot-Entrance-type with a
high accuracy of the mechanical structure and a good
shockproof capability. The loader in the DVD player is not
belonging to component serviceable part. Hence, it is
necessary to clarify if any fault condition of the player is caused
by the loader, before replacing the loader.
In the DVD system, the linkage between loader and the
decoder board is the ATAPI standard. The loader is a stand-
alone system, the servo control board of the loader is
consisting all necessary device for disc reading and primary
decode, such as CPU, DSP and data memory. Once a stable
voltage is supplied to the loader, the loader itself can operate
even without connecting to the decoder board. By observing
the movement of optical assembly part and the major axis
motor will know the loader is operating. Hence, to clarify
whether the loader is in fault condition, remove the 40 pins wire
assembly and observe the movement descript above. If the
+12V and +5V supply voltage is normal by measure, and no
any movement can be obtained, the loader is faulty.
One the other hand, If the loader can operate alone, but lost it
after 40 pins connecter is reconnected, then the decoder board
or the decoder chipset itself may get faulty. In this situation,
check the circuit between the two modules (loader and decoder
board) or replace the decoder IC chipset if necessary.
The disc loader is having two type of laser pickup optical, one
for DVD disc, while the other one works for VCD or CD. If any
one type of disc (DVD or VCD / CD) dose not be identified. It
can be sure that the fault is come from the disc Loader.
Y1
4MHz
C312
22P
180702
COAX
1
2
3
OPT
1
2
3
180702