Reflow Guidelines; B.6 Reflow Guidelines - Intel Quark SoC X1000 Design Manual

Exposed Pad* (e-Pad*) Design and SMT Assembly Guide—Intel
B.6

Reflow Guidelines

The typical reflow profile consists of four sections. In the preheat section, the PCB
assembly should be preheated at the rate of 1 to 2 °C/sec to start the solvent
evaporation and to avoid thermal shock. The assembly should then be thermally
soaked for 60 to 120 seconds to remove solder paste volatiles and for activation of flux.
The reflow section of the profile, the time above liquidus should be between 45 to 60
seconds with a peak temperature in the range of 245 to 250 °C, and the duration at the
peak should not exceed 30 seconds. Finally, the assembly should undergo cool down in
the fourth section of the profile. A typical profile band is provided in Figure 106, in
which 220 °C is referred to as an approximation of the liquidus point. The actual profile
parameters depend upon the solder paste used and specific recommendations from the
solder paste manufacturers should be followed.
Figure 107. Typical Profile Band
Notes:
1. Preheat: 125 °C -220 °C, 150 - 210 s at 0.4 k/s to 1.0 k/s
2. Time at T > 220 °C: 60 - 90 s
3. Peak Temperature: 245-250 °C
4. Peak time: 10 - 30 s
5. Cooling rate: <= 6 k/s
6. Time from 25 °C to Peak: 240 – 360 s
7. Intel recommends a maximum solder void of 50% after reflow.
Note: Contact your Intel representative for any designs unable to meet the recommended
guidance for E-pad implementation.
June 2014
Order Number: 330258-002US
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Quark™ SoC X1000
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Intel Quark™ SoC X1000
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