40a digital megadlynx, Non-isolated dc-dc power modules, Data sheet – GE Industrial Solutions 40A Digital MegaDLynx User Manual
Page 35: Surface mount information
GE
Data Sheet
40A Digital MegaDLynx
TM
: Non-Isolated DC-DC Power Modules
4.5Vdc –14.4Vdc input; 0.45Vdc to 2.0Vdc output; 40A Output Current
April 24, 2013
©2012 General Electric Company. All rights reserved.
Page 35
Surface Mount Information
Pick and Place
The 40A Digital Mega DLynx
TM
modules use an open frame
construction and are designed for a fully automated
assembly process. The modules are fitted with a label
designed to provide a large surface area for pick and place
operations. The label meets all the requirements for surface
mount processing, as well as safety standards, and is able to
withstand reflow temperatures of up to 300
o
C. The label also
carries product information such as product code, serial
number and the location of manufacture.
Nozzle Recommendations
The module weight has been kept to a minimum by using
open frame construction. Variables such as nozzle size, tip
style, vacuum pressure and placement speed should be
considered to optimize this process. The minimum
recommended inside nozzle diameter for reliable operation is
3mm. The maximum nozzle outer diameter, which will safely
fit within the allowable component spacing, is 7 mm.
Bottom Side / First Side Assembly
This module is not recommended for assembly on the bottom
side of a customer board. If such an assembly is attempted,
components may fall off the module during the second reflow
process.
Lead Free Soldering
The modules are lead-free (Pb-free) and RoHS compliant and
fully compatible in a Pb-free soldering process. Failure to
observe the instructions below may result in the failure of or
cause damage to the modules and can adversely affect long-
term reliability.
Pb-free Reflow Profile
Power Systems will comply with J-STD-020 Rev. C
(Moisture/Reflow Sensitivity Classification for Nonhermetic
Solid State Surface Mount Devices) for both Pb-free solder
profiles and MSL classification procedures. This standard
provides a recommended forced-air-convection reflow profile
based on the volume and thickness of the package (table 4-
2). The suggested Pb-free solder paste is Sn/Ag/Cu (SAC). The
recommended linear reflow profile using Sn/Ag/Cu solder is
shown in Fig. 32.
Soldering outside of the recommended
profile requires testing to verify results and performance.
MSL Rating
The 40A Digital Mega DLynx
TM
modules have a MSL rating of
2a.
Storage and Handling
The recommended storage environment and handling
procedures for moisture-sensitive surface mount packages is
detailed in J-STD-033 Rev. A (Handling, Packing, Shipping and
Use of Moisture/Reflow Sensitive Surface Mount Devices).
Moisture barrier bags (MBB) with desiccant are required for
MSL ratings of 2 or greater. These sealed packages should
not be broken until time of use. Once the original package is
broken, the floor life of the product at conditions of
30°C
and 60% relative humidity varies according to the MSL rating
(see J-STD-033A). The shelf life for dry packed SMT packages
will be a minimum of 12 months from the bag seal date,
when stored at the following conditions: < 40° C, < 90%
relative humidity.
Figure 32. Recommended linear reflow profile using
Sn/Ag/Cu solder.
Post Solder Cleaning and Drying Considerations
Post solder cleaning is usually the final circuit-board
assembly process prior to electrical board testing. The result
of inadequate cleaning and drying can affect both the
reliability of a power module and the testability of the
finished circuit-board assembly. For guidance on
appropriate soldering, cleaning and drying procedures, refer
to Board Mounted Power Modules: Soldering and Cleaning
Application Note (AN04-001).
Per J-STD-020 Rev. C
0
50
100
150
200
250
300
Reflow Time (Seconds)
R
ef
lo
w
T
em
p
(
°C
)
Heating Zone
1°C/Second
Peak Temp 260°C
* Min. Time Above 235°C
15 Seconds
*Time Above 217°C
60 Seconds
Cooling
Zone