NORA-B1 series - System integration manual
UBX-20027617 - R02
Handling and soldering
Page 36 of 58
C1-Public
The module is compatible with the industrial reflow profile for common SAC type RoHS solders. Use
of "No Clean" solder paste is strongly recommended.
The reflow profile used is dependent on the thermal mass of the entire populated PCB, heat transfer
efficiency of the oven, and type of solder paste used. The optimal soldering profile used must be
trimmed for each case depending on the specific process and PCB layout.
Process parameter
Unit
Target
Pre-heat
Ramp up rate to T
SMIN
K/s
3
T
SMIN
°C
150
T
SMAX
°C
200
t
S
(from +25 °C)
s
150
t
S
(Pre-heat)
s
60 to 120
Peak
T
L
°C
217
t
L
(time above T
L
)
s
40 to 60
T
P
(absolute max)
°C
245
Cooling
Ramp-down from T
L
K/s
4
Allowed soldering cycles
-
1
Table 12: Recommended reflow profile
Figure 11: Reflow profile
☞
Lower value of T
P
and slower ramp down rate (2 – 3 °C/sec) is preferred.
☞
After reflow soldering, optical inspection of the modules is recommended to verify proper
alignment.
⚠
Target values in Table 12 should be taken as general guidelines for a SAC type Pb-free process.
Refer to the JEDEC J-STD-020C [9] standard for further information.
5.3.2
Cleaning
Cleaning the modules is not recommended. Residues underneath the modules cannot be easily
removed with a washing process.
•
Cleaning with water will lead to capillary effects where water is absorbed in the gap between the
host board and the module. The combination of residues of soldering flux and encapsulated water
can lead to short circuits or resistor-like interconnections between neighboring pads. Water will
also damage the sticker and the ink-jet printed text.
