Symphonic ST27S3, Service Manual

Page: 10 / 52

3-3 L6115STA
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 "
I
" 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 prop-
erly 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 cloth-
ing will not escape through the body grounding band,
be careful to avoid contacting semiconductors with
your clothing.
Example :
Pin 1 of the Flat Pack-IC
is indicated by a " " mark.
Fig. S-1-7
Presolder
CBA
Flat Pack-IC
Fig. S-1-8
CBA
<Incorrect>
CBA
Grounding Band
Conductive Sheet or
Copper Plate
1M
Ω
1M
Ω
<Correct>