Mitsubishi DD-4021, Руководство по обслуживанию

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2. Installation
(1) Using desoldering braid, remove the solder from the
foil of each pin of the flat pack-IC on the CBA so you
can install a replacement flat pack-IC more easily.
(2) The "
●
" mark on the flat pack-IC indicates pin 1.
(See Fig. S-1-7.) Be sure this mark matches the 1
on the PCB when positioning for installation. Then
pre- solder the four corners of the flat pack-IC. (See
Fig. S-1-8.)
(3) Solder all pins of the flat pack-IC. Be sure that none
of the pins have solder bridges.
Instructions for Handling
Semiconductors
Electrostatic breakdown of the semiconductors may
occur due to a potential difference caused by electro-
static charge during unpacking or repair work.
1. Ground for Human Body
Be sure to wear a grounding band (1M
Ω
) that is properly
grounded to remove any static electricity that may be
charged on the body.
2. Ground for Workbench
Be sure to place a conductive sheet or copper plate with
proper grounding (1M
Ω
) on the workbench or other
surface, where the semiconductors are to be placed.
Because the static electricity charge on clothing will not
escape through the body grounding band, be careful to
avoid contacting semiconductors with your clothing.
CBA
CBA
Grounding Band
Conductive Sheet or
Copper Plate
1M
Ω
1M
Ω
Presolder
Soldering Iron
CBA
Flat Pack-IC
Example :
Pin 1 of the Flat Pack-IC
is indicated by a "
●
" mark.
Fig. S-1-7
Fig. S-1-8
< Incorrect >
< Correct >
1-4-3 DVD_NOTE