Datasheet

Solder Paste
183
Time
Temperature(
C)°
165
135
Maximum235 ,Minimum195° °C C
Minimum60s
Maximum120s
Minimum30s
Maximum90s
EXAMPLE REFLOW PROFILE
220
Time
Temperature(
C)°
180
150
Maximum260 ,Minimum230° °C C
Minimum60s
Maximum120s
Minimum30s
Maximum90s
THS7319
www.ti.com .............................................................................................................................................................. SBOS468A – JUNE 2009 – REVISED JULY 2009
TI recommends using a Type 3 or finer solder paste
when mounting the MicrostarCSP. This paste offers
the following advantages:
• It acts as a flux to aid wetting of the solder ball to
the PCB land.
• The adhesive properties of the paste hold the
component in place during the reflow process.
• Solder paste selection is normally driven by the
overall system-assembly requirements. In general,
the no clean compositions are preferred because
of the difficulty in cleaning below the mounted
components. Customers should check with the
solder-paste vendors regarding electrical issues
Figure 55. SnPb Temperature Profile Example
from residues left on the board.
TI recommends a pressure safety zone in mounting
the MicrostarCSP package. The recommended force
should be controlled to 5N maximum for static and
2.5N for impact.
The MicrostarCSP package solder ball is compatible
with lead and lead-free pastes. Example reflow
profiles for SnPb and Pb-free are shown in Figure 55
and Figure 56 . Table 4 lists the profiles for SnPb and
Pb-free reflow.
TI recommends that the solder-paste manufacturer
temperature profile be used to optimize flux activity
within the MSL guidelines for the most
Figure 56. Pb-Free Temperature Profile Example
thermally-sensitive component. Refer to J-STD-033
for more details on the MSL classification.
Table 4. SnPb and Pb-Free Example Reflow Profiles
PARAMETER SnPb Pb-FREE
Ramp rate 3 ° C/second, maximum 3 ° C/second, maximum
135 ° C to 165 ° C 150 ° C to 180 ° C
Preheat
60 to 120 seconds 60 to 120 seconds
183 ° C 220 ° C
Time above liquids
30 to 90 seconds 30 to 90 seconds
Peak temperature 235 ° C 260 ° C +0/ – 5 ° C
Time within 5 ° C peak temperature 10 to 20 seconds 10 to 20 seconds
Ramp down rate 6 ° C/second, maximum 6 ° C/second, maximum
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Product Folder Link(s): THS7319