GE Industrial Solutions PicoTLynx 3A - Manual (Page 23)

GE
Data Sheet
PicoTLynx TM 3A: Non-Isolated DC-DC Power Modules
2.4Vdc –5.5Vdc input; 0.6Vdc to 3.63Vdc output; 3A Output Current
September 11, 2013 ©2013 General Electric Company. All rights reserved. Page 23
Surface Mount Information
Pick and Place
The Pico TLynx TM 3A 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. If assembly on the bottom side is planned, please
contact GE for special manufacturing process instructions.
Only ruggedized (-D version) modules with additional epoxy will
work with a customer’s first side assembly. For other versions,
first side assembly should be avoided
Lead Free Soldering
The Pico TLynx TM 3A 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. 47.
Soldering outside of the recommended profile requires testing to
verify results and performance. For questions regarding Land
grid array(LGA) soldering, solder volume; please contact GE for
special manufacturing process instructions
MSL Rating
The Pico TLynx TM 3A 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.
Per J-STD-020 Rev. C
0
50
100
150
200
250
300
Reflow Time (Seconds)
R
efl
ow
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
Fi
gure 47. 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).