File name p35.pdfRepair Tips 105B2 CM23 GSIII 35
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0. Warning preferably be equipped with a thermal control (soldering
temperature: 225 to 250 C).
o
All ICs and many other semi-conductors are susceptible to - The chip, once removed, must never be reused.
electrostatic discharges (ESD). Careless handling during
repair can reduce life drastically. When repairing, make sure 1.4 Attachment of SMDs
that you are connected with the same potential as the mass - Locate the SMD on the solder lands by means of tweezers
of the unit via a wrist wrap with resistance. Keep components and solder the component on one side. Ensure that the
and tools also at the same potential ! component is positioned correctly on the solder lands (see
Fig.2A).
- Next complete the soldering of the terminals of the
1. Servicing of SMDs (Surface Mounted Devices) component (see Fiq. 2B).
1.1 General cautions on handling and storage Fig. 2 MOUNTING
- Oxidation on the terminals of SMDs results in poor soldering. e.g. A PAIR OF TWEEZERS
Do not handle SMDs with bare hands.
- Avoid using storage places that are sensitive to oxidation
such as places with sulphur or chlorine gas, direct sunlight, A
high temperatures or a high degree of humidity. The
SOLDER
capacitance or resistance value of the SMDs may be 0.5 - 0.8 mm
affected by this. SOLDERING
PRESURE
- Rough handling of circuit boards containing SMDs may IRON
cause damage to the components as well as the circuit
boards. Circuit boards containing SMDs should never be
bent or flexed. Different circuit board materials expand and SOLDERING TIME
< 3 sec/side
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