LMX9820 National Semiconductor, LMX9820 Datasheet - Page 36

• Manufacturer Part Number: LMX9820
• Description: Bluetooth Serial Port Module
• Manufacturer: National Semiconductor

www.national.com
15.0 Soldering
The LMX9820 bumps are designed to melt as part of the
Surface Mount Assembly (SMA) process. The LMX9820 is
assembled with a high temperature solder alloy to ensure
there are no re-reflow conditions imposed upon the module
when reflowed to a PCB with these typical low temperature
60/40 (S = 183°C, L = 188°C), 62/36/2 (E = 179°C), or
63/37 (E = 183°C) solder alloys.
Where:
• S: Solidus
• L: Liquidus
1.
Parameter
PCB Land Pad Diameter
PCB Solder Mask Opening
PCB Finish (HASL details)
Stencil Aperture
Stencil Thickness
Solder Paste Used
Flux Cleaning Process
Reflow Profiles
– Denotes the points in a phase diagram representing
– Denotes the points in a phase diagram representing
Typically defined by customer.
the temperature at which the solder composition be-
gins to melt during heating, or complete freezing dur-
ing cooling.
Table 39. Soldering Details
36
Low temperature 60/40 (S = 183°C, L = 188°C), 62/36/2 (E
• E: Eutectic
The low temperature solder alloy will reflow with the solder
bump and provide the maximum allowable solder joint reli-
ability.
Reflow at a peak of 215 --> 220°C (approximately 30 sec-
onds at peak) [not to exceed 225°C; measured in close
proximity of the modules] to avoid any potential re-reflow
conditions.
Table 39 and Figure 26 on page 37 provide the soldering
details required to properly solder the LMX9820 to stan-
dard PCBs. The illustration serves only as a guide and
National is not liable if a selected profile does not work.
– Denotes solid to liquid without a plastic phase.
= 179°C), or 63/37 (E = 183°C) solder alloys
63/37 (difference in thickness < 28 micron)
the temperature at which the solder has molten com-
ponents. The temperature that melting starts at.
See Figure 26 on page 37
No Clean Flux System
Value
24 mil
30 mil
28 mil
5 mil
1
1