JVC HR-D540EE - Semiconductors

3.2.6 Semiconductors
1. Digital transistor
<a
R2
DTA114T
RA T mark only
<
2. Chip transistor
Cc Cc
E E
Ge
c
E
E
(Standard type)
3. Chip diode
DAP202U MA141WK
MA151WA MA151WK
MA141WA DAN202U
2 A2
3A 3c
1 Al
DA204U
DA204K 3
: Ge
: 2
Al ; 1
Note:
The digital transistor includes built in resistors.
It features small size and high reliability.
Both PNP and NPN types are available.
Uses:
Inverter, Interface, driver circuits.
3.2.7 Replacement of chip parts
For replacing chip parts, proceed it as follows.
Use a well insulated fine-tipped soldering iron (approx. 17 W,
130°C ~ 260°C in temp.).
In addition, it is recommended to use a soldering iron (55 W
approx.) with solder absorber for convenience.
Caution: e Do not apply heat for more than 3 seconds.
e Do not rub electrodes.
e Do not reuse chips removed once. Discard them.
e Supplementary cementing is not required.
1. Soldered condition of chip parts
@ Resistors, capacitors, etc.
Chip part
Pattern Solder
Cement
Fig. 3-2-1 Soldering condition-1
@ Transistors, diodes, etc.
Chip part
Pattern Solder
Board
|
:
Cement
Fig. 3-2-2 Soldering condition-2
2. How to remove chip parts
@ Resistors, capacitors, etc.
1) Set a chip parts replacing tool
onto the chip parts to hold it
down. Chip parts
2) Unsolder at a side of the chip replacing toe!
parts. J
Fig. 3-2-3 R/C removal-1
3) Remove the chip parts by twist-
ing and sliding it.
Fig. 3-2-4 R/C removal-2
3-3
3. How to remove transistors, diode.
1) Unsolder at the one-iead side of
the chip parts.
Tweezers
Fig. 3-2-5 Tr/Diode removal-1
2) Lift the unsoldered side upwards.
Fig. 3-2-6 Tr/Diode removal-2
3) Heat the other two leads simul-
taneously and remove the chip
parts upwards.
|
Fig.
3-2-7
Tr/Diode
removal-3
4. Preheating and soldering
When
setting
new
chip
parts,
especially
capacitors,
but
except
transistors,
preheat
them
with
hot
air
(150°C
approx.)
by
use
of
a
blower
type
of
hair
dryer
for
about
2
minutes
just
before
soldering.
For
soldering,
use
a
solder-
ing
iron
of
30
watt
approximately.
3-4
5.
How
to
set
and
solder
chip
parts
1) Presolder the contact points of
the circuit pattern to which the
chip parts will be soldered.
Fig. 3-2-8 Soldering-1
2) Holding down the chip parts
with the chip parts replacing tool,
solder it with a soldering iron.
Fig. 3-2-9 Soldering-2