PCB design and manufacturing Flux and cleaning
XBee®/XBee-PRO SX RF Module User Guide
205
Time (seconds) Temperature (degrees C)
30 65
60 100
90 135
120 160
150 195
180 240
210 260
The maximum temperature should not exceed 260 °C.
The SX device will reflow during this cycle, and therefore must not be reflowed upside down. Take care
not to jar the device while the solder is molten, as this can remove components under the shield from
their required locations.
The device has a Moisture Sensitivity Level (MSL) of 3. When using this product, consider the relative
requirements in accordance with standard IPC/JEDEC J-STD-020.
In addition, note the following conditions:
a. Calculated shelf life in sealed bag: 12 months at < 40 °C and < 90% relative humidity (RH).
b. Environmental condition during the production: 30 °C /60% RH according to IPC/JEDEC J-STD-
033C, paragraphs 5 through 7.
c. The time between the opening of the sealed bag and the start of the reflow process cannot
exceed 168 hours if condition b) is met.
d. Baking is required if conditions b) or c) are not met.
e. Baking is required if the humidity indicator inside the bag indicates a RH of 10% more.
f. If baking is required, bake modules in trays stacked no more than 10 high for 4-6 hours at
125°C.
Flux and cleaning
We recommend that you use a “no clean” solder paste in assembling these devices. This eliminates
the clean step and ensures that you do not leave unwanted residual flux under the device where it is
difficult to remove. In addition:
n Cleaning with liquids can result in liquid remaining under the device or in the gap between the
device and the host PCB. This can lead to unintended connections between pads.
n The residual moisture and flux residue under the device are not easily seen during an
inspection process.
Rework
Once you mount the device, do not perform rework on the SX device (for example, removing it from
the host PCB).