ICD-PX312, ICD-PX312D, ICD-PX312F, ICD-PX312 M, ICD-PX312M (serv.man2) - Sony Audio Service Manual (repair manual). Page 3

1-1.  Battery Case Lid .............................................................   4
1-2.  Case Front Assy, Speaker (SP101)..................................   5
1-3.  Complete Main Board .....................................................   6
1-4.  Liquid Crystal Display Panel (LCD101), 
 

Main Board .....................................................................   6

TEST  MODE 

 ............................................................  

7

3-1.  Block Diagram –Main Section– .....................................   13
3-2.  Block Diagram –Power/Display Section– ......................   14
3-3.  Printed Wiring Board –Main Section (1/2)– ...................   16
3-4.  Printed Wiring Board –Main Section (2/2) .....................   17
3-5.  Schematic Diagram –Main Section (1/6)– ......................   18
3-6.  Schematic Diagram –Main Section (2/6)– ......................   19
3-7.  Schematic Diagram –Main Section (3/6)– ......................   20
3-8.  Schematic Diagram –Main Section (4/6)– ......................   21
3-9.  Schematic Diagram –Main Section (5/6)– ......................   22
3-10.  Schematic Diagram –Main Section (6/6)– ......................   23

4-1.  Case (Front) Section .......................................................   33
4-2.  Case (Rear) Section ........................................................   34

   ..............................   35

UNLEADED  SOLDER
Boards requiring use of unleaded solder are printed with the lead-
free mark (LF) indicating the solder contains no lead.
(Caution:  Some printed circuit boards may not come printed with 

the lead free mark due to their particular size)

Unleaded solder has the following characteristics.
•  Unleaded solder melts at a temperature about 40 °C higher 

than ordinary solder.

 

Ordinary soldering irons can be used but the iron tip has to be 
applied to the solder joint for a slightly longer time.

 

Soldering irons using a temperature regulator should be set to 
about 350 °C.
Caution: The printed pattern (copper foil) may peel away if 

the heated tip is applied for too long, so be careful!

• 

Strong viscosity

 

Unleaded solder is more viscous (sticky, less prone to fl ow) 
than ordinary solder so use caution not to let solder bridges 
occur such as on IC pins, etc.

• 

Usable with ordinary solder

 

It is best to use only unleaded solder but unleaded solder may 
also be added to ordinary solder.

NOTES  ON  CHIP  COMPONENT  REPLACEMENT
• 

Never reuse a disconnected chip component.

• 

Notice that the minus side of a tantalum capacitor may be dam-
aged by heat.

FLEXIBLE  CIRCUIT  BOARD  REPAIRING
• 

Keep the temperature of soldering iron around 270 °C during 
repairing.

• 

Do not touch the soldering iron on the same conductor of the 
circuit board (within 3 times).

• 

Be careful not to apply force on the conductor when soldering 
or unsoldering.

NOTE  FOR  REPLACEMENT  OF THE MAIN  BOARD
When the main board are exchanged, it is necessary to write the 
fi rmware newly.
Refer to each service headquarters about details.

CAUTION
Risk of explosion if battery is replaced by an incorrect type.
Dispose of used batteries according to the instructions.