STPCI2 STMicroelectronics, STPCI2 Datasheet - Page 74

• Manufacturer Part Number: STPCI2
• Description: STPC ATLAS DATASHEET - X86 CORE PC COMPATIBLE SYS
• Manufacturer: STMicroelectronics

MECHANICAL DATA
5.3. SOLDERING RECOMMENDATIONS
High quality, low defect soldering requires
identifying the optimum temperature profile for
reflowing the solder paste, therefore optimizing
the process. The heating and cooling rise rates
must be compatible with the solder paste and
components. A typical profile consists of a
preheat, dryout, reflow and cooling sections.
The most critical parameter in the preheat
section is to minimize the rate of temperature rise
to less than
thermal
components.
74/111
250
200
150
100
50
0
Temperature ( C )
0
shock
PREHEAT
C / second, in order to minimize
on
Figure 5-7. Reflow soldering temperature range
the
semi-conductor
DRYOUT
Issue 1.0 - July 24, 2002
Dryout section is used primarily to ensure that
the solder paste is fully dried before hitting reflow
temperatures.
Solder reflow is accomplished in the reflow zone,
where the solder paste is elevated to a
temperature greater than the melting point of the
solder. Melting temperature must be exceeded by
approximately 20 C to ensure quality reflow.
In reality the profile is not a line, but rather a range
of temperatures all solder joints must be
exposed. The total temperature deviation from
component thermal mismatch, oven loading and
oven uniformity must be within the band.
REFLOW
240
COOLING
Time ( s )