akira DM-300P User manual

Portable Disc Player
Service Manual

2
Model No.: DM-300P
Version: 1.0
MODEL:
DM-300P

3
Model No.: DM-300P
Version: 1.0
CONTENTS
MAIN BOARD CIRCUIT DIAGRAM & FUNCTION EXPLANATION ...................................... 4
TROUBLE SHOOTING................................................................................................................... 5
EASY DAMAGED COMPONENT & BADNESS PHENOMENON LIST.................................... 8
CIRCUIT DIAGRAM....................................................................................................................... 9

4
Model No.: DM-300P
Version: 1.0
MAIN BOARD CIRCUIT DIAGRAM & FUNCTION
EXPLANATION
Mechanism (SONY 900AA): Read disc signal
RF (SONY A2550N): Signal Amplifier
DSP (SONY CXD3068Q): Digital Signal
Processor
MPEG (SPCA716A) :
MPEG-1 Decoder
4 DC TO DC（ROAM
D5901）: Mechanism
power driver+ Power
Circuit
Power
5 VIDEO
(SPCA717A): Video
processor
AUDIO (WM8714+DF2308):
Audio processor (A/D
Transfer+ Amplify)
SDRAM
(SDRAM4*16M-80):
D
y
namic Stora
g
e
8 ROOM (2M
FLASH):
Storage
VIDEO OUT AUDIO OUT

5
Model No.: DM-300P
Version: 1.0
TROUBLE SHOOTING
1. There is smutch on the touching point of battery chip, or the chromed
place of it affects the function due to serious rusting. (Judgment: keep
pressing the ‘turn-on’ key, the voltage between negative of diode (D1
1N4002) and cathode of battery chip is lower than 2.3V.
2. Power socket (DC2) is damaged (bad touching between 2 pin and 3
pin)。(Judgment: bad connection between cathode of battery chip and
power).
3. Capacitance on main board 30 C35 (1UF/0603) is bad or its capacity is
low.
4. Amplifier multiple of main board Q3 (S8050D) is less than 200.
Batteries can’t play
CD
Correction process:
Check battery chip Clean the smutch or change
battery chip
Check power
socket
Change power socket
Check the
capacitance of
C30C35 on main
board
Change capacitance
Check Q3 on main
board
Change dynatron
 OK
Yes
Yes
Yes
Yes
OK
OK
OK
OK
NG
NG
NG

6
Model No.: DM-300P
Version: 1.0
1. Power socket (DC2) is damaged (bad 3pin). (Judgment: when keep
pressing ‘turn-on’ switch, there is no voltage between negative of D1
1N4002 and ground).
2. The circuit from DC to DC (AT5801 IC and circumjacent circuit) is bad.
The most possible component is Q6 (S8050D).
3. ROM (SST39VF020/040 IC) is in bad connection or losing data.
4. ‘PLAY’ button is in bad connection.
No display when
switch on the player
Correction process:
Check power socket Change the socket
Check Q6。Change Q6。
Check ROM。Reinstall or change ROM
Check the
p
anel Clean the touching point
 OK
1 Please ask the technician for help
2 Please send back 2~3pcs defective
sample for our analysis.
Yes
Yes
Yes
Yes
Yes
OK
OK
OK
OK
NG
NG

7
Model No.: DM-300P
Version: 1.0
1. The screws on Control Board are loosing or the LCD is broken, due to
bad protection during transportation.
2. Bad Control Board.
Absent Stroke on
LCD
Correction process:
Some button
malfunction or
touch-feeling not
well
Cause analysis and Correction method:
1) There are smutch between button and main board. Please clean smutch.
2) Bad Button Housing: Please chance button housing.
3) Bad Control Board: Please ask Engineer to repair it.
Show ‘No Disk”
when reading disc
Cause analysis and Correction method:
1) Improper Disc：Serious-Scratched disk or the format of Disc is out of
MPEG-1Standard.
2) There are dusts on Pick up lens: please clean the lens with professional
cleaning disc.
Check if the scre
w
is loosing
Fix it firmly
Check if the LCD is
crashed Change LCD
Check if Control
Board is bad
Change bad
component or Control
Board
 OK
Yes
Yes
NG
NG
NG
OK
OK
OK

8
Model No.: DM-300P
Version: 1.0
EASY DAMAGED COMPONENT AND BADNESS
PHENOMENON LIST
COMPONENT BADNESS PHENOMENON
AC power AC no power.
Line control Malfunction.
Batteries for remote controller No controlling function.
Bettery chip No power.
Power socket No power.
Q6 (C4115S) Weak power can’t start the unit or no. 3.3V power
voltage.
HOLD switch Malfunction.
Open switch Show “OPEN” or power off when turn on the
unit.
Touching between ROOM (2M FLASH) and
socket
No feekback when turn on the unit.
Earphone socket No sound or single sound or interrupted sound.
Connecting housing of control board No feednack or no display when turn on the unit.

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Model No.: DM-300P
Version: 1.0
CIRCUIT DIAGRAM

10
Model No.: DM-300P
Version: 1.0

11
Model No.: DM-300P
Version: 1.0