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Each precaution in this manual should be followed during servicing.

Components identified with the IEC symbol

in the parts list are special significance to safety. When replacing a component identified with

, use only the replacement parts designated, or parts with the same ratings or resistance, wattage, or voltage that are designated in the

parts list in this manual. Leakage-current or resistance measurements must be made to determine that exposed parts are acceptably

insulated from the supply circuit before retuming the product to the customer.

Some semiconductor (solid state) devices can be damaged easily by static electricity. Such components commonly are called

Electrostatically Sensitive (ES) Devices. Examples of typical ES devices are integrated circuits and some field effect transistors and

semiconductor "chip" components.

The following techniques should be used to help reduce the incidence of component damage caused by static electricity.

1. Immediately before handling any semiconductor component or semiconductor-equipped assembly, drain off any electrostatic charge on

your body by touching a known earth ground. Alternatively, obtain and wear a commercially available discharging wrist strap device,

which should be removed for potential shock reasons prior to applying power to the unit under test.

2. After removing an electrical assembly equipped with ES devices, place the assembly on a conductive surface such as aluminum foil, to

prevent electrostatic charge build-up or exposure of the assembly.

3. Use only a grounded-tip soldering iron to solder or unsolder ES devices.

4. Use only an anti-static solder removal device. Some solder removal devices not classified as "anti-static" can generate electrical charges

sufficient to damage ES devices.

5. Do not use freon-propelled chemicals. These can generate electrical change sufficient to damage ES devices.

6. Do not remove a replacement ES device from its protective package until immediately before you are ready to install it. (Most replacement

ES devices are packaged with leads electrically shorted together by conductive foam, aluminum foil or comparable conductive material.)

7. Immediately before removing the protective material from the leads of a replacement ES device, touch the protective material to the

chassis or circuit assembly into which the device will be installed.

Be sure no power is applied to the chassis or circuit, and observe all other safety precautions.

8. Minimize bodily motions when handling unpackaged replacement ES devices. (Otherwise harmless motion such as the brushing together

or your clothes fabric or the lifting of your foot from a carpeted floor can generate static electricity sufficient to damage an ES devices.

CAUTION :

2-2

The following check should be performed for the continued
protection of the customer and service technician.

Measure leakage current to a known earth ground (water
pipe, conduit, etc.) by connecting a leakage current tester
between the earth ground and all exposed metal parts of the
appliance (input/output terminals, screwheads, metal
overlays, control shaft, etc.). Plug the AC line cord of the
appliance directly into a 120V AC 60Hz outlet and turn the
AC power switch on. Any current measured must not exceed
o.5mA.

Device

under

test

Test all
exposed metal
surfaces

Also test with
plug reversed
(Using AC adapter
plug as required)

Leakage
current
tester

Reading should
not be above
0.5mA

Earth
ground

2-3

3-1

•

Special information for BGA-ICs:

• For sets produced before 1.1.2005 (except products

of 2004), containing leaded solder-alloy and
components, all needed spare-parts will be available
till the end of the service-period. For repair of such
sets nothing changes.

• BGA-de-/soldering (+ baking instructions)

You will find this and more technical information within 
the “magazine”, chapter “workshop news”.

For additional questions please contact your local 
repair-helpdesk.

How to Remove / Install Flat Pack-IC

Special Information of BGA IC & Flat Pack-IC

1. Removal

With Hot-Air Flat Pack-IC Desoldering Machine:

1. Prepare the hot-air flat pack-IC desoldering

machine, then apply hot air to the Flat Pack-IC
(about 5 to 6 seconds). (Fig. S-1-1)

2. Remove the flat pack-IC with tweezers while

applying the hot air.

3. Bottom of the flat pack-IC is fixed with glue to the

CBA; when removing entire flat pack-IC, first apply
soldering iron to center of the flat pack-IC and heat
up. Then remove (glue will be melted). (Fig. S-1-6)

4. Release the flat pack-IC from the CBA using

tweezers. (Fig. S-1-6)

CAUTION:

1. The Flat Pack-IC shape may differ by models. Use

an appropriate hot-air flat pack-IC desoldering
machine, whose shape matches that of the Flat
Pack-IC.

2. Do not supply hot air to the chip parts around the

flat pack-IC for over 6 seconds because damage
to the chip parts may occur. Put masking tape
around the flat pack-IC to protect other parts from
damage. (Fig. S-1-2)

Fig. S-1-1

3. The flat pack-IC on the CBA is affixed with glue, so

be careful not to break or damage the foil of each
pin or the solder lands under the IC when
removing it.

With Soldering Iron:

1. Using desoldering braid, remove the solder from

all pins of the flat pack-IC. When you use solder
flux which is applied to all pins of the flat pack-IC,
you can remove it easily. (Fig. S-1-3)

2. Lift each lead of the flat pack-IC upward one by

one, using a sharp pin or wire to which solder will
not adhere (iron wire). When heating the pins, use
a fine tip soldering iron or a hot air desoldering
machine. (Fig. S-1-4)

3. Bottom of the flat pack-IC is fixed with glue to the

CBA; when removing entire flat pack-IC, first apply
soldering iron to center of the flat pack-IC and heat
up. Then remove (glue will be melted). (Fig. S-1-6)

4. Release the flat pack-IC from the CBA using

tweezers. (Fig. S-1-6)

With Iron Wire:

1. Using desoldering braid, remove the solder from

all pins of the flat pack-IC. When you use solder
flux which is applied to all pins of the flat pack-IC,
you can remove it easily. (Fig. S-1-3)

2. Affix the wire to a workbench or solid mounting

point, as shown in Fig. S-1-5.

3. While heating the pins using a fine tip soldering

iron or hot air blower, pull up the wire as the solder
melts so as to lift the IC leads from the CBA
contact pads as shown in Fig. S-1-5.

4. Bottom of the flat pack-IC is fixed with glue to the

CBA; when removing entire flat pack-IC, first apply
soldering iron to center of the flat pack-IC and heat
up. Then remove (glue will be melted). (Fig. S-1-6)

5. Release the flat pack-IC from the CBA using

tweezers. (Fig. S-1-6)

Note:  When 

using 

a soldering iron, care must be 

taken to ensure that the flat pack-IC is not 
being held by glue. When the flat pack-IC is 
removed from the CBA, handle it gently 
because it may be damaged if force is applied.

Hot-air
Flat Pack-IC
Desoldering
Machine

CBA

Flat Pack-IC

Tweezers

Masking
Tape

Fig. S-1-2

Flat Pack-IC

Desoldering Braid

Soldering Iron

Fig. S-1-3

Fine Tip
Soldering Iron

Sharp
Pin

Fig. S-1-4

To Solid 
Mounting Point

Soldering Iron

Iron Wire

or

Hot Air Blower

Fig. S-1-5

Fine Tip
Soldering Iron

CBA

Flat Pack-IC

Tweezers

Fig. S-1-6

3-2

Special Information of BGA IC & Flat Pack- IC