GE Industrial Solutions EVW020A0A Series (Eighth-Brick) - Manual (Page 11)

Data Sheet
September 7, 2012
EVW020A0A Series Eighth-Brick Power Modules
36–75Vdc Input; 5.0Vdc Output; 20A Output Current
LINEAGE POWER 11
Surface Mount Information (continued)
solder joint. There are several types of SMT reflow
technologies currently used in the industry. These
surface mount power modules can be reliably
soldered using natural forced convection, IR (radiant
infrared), or a combination of convection/IR.
Tin Lead Soldering
The EVW020A0A power modules are lead free
modules and can be soldered either in a lead-free
solder process or in a conventional Tin/Lead (Sn/Pb)
process. It is recommended that the customer review
data sheets in order to customize the solder reflow
profile for each application board assembly. The
following instructions must be observed when
soldering these units. Failure to observe these
instructions may result in the failure of or cause
damage to the modules, and can adversely affect
long-term reliability.
In a conventional Tin/Lead (Sn/Pb) solder process
peak reflow temperatures are limited to less than
235
o C. Typically, the eutectic solder melts at 183 o C,
wets the land, and subsequently wicks the device
connection. Sufficient time must be allowed to fuse
the plating on the connection to ensure a reliable
solder joint. There are several types of SMT reflow
technologies currently used in the industry. These
surface mount power modules can be reliably
soldered using natural forced convection, IR (radiant
infrared), or a combination of convection/IR. For
reliable soldering the solder reflow profile should be
established by accurately measuring the modules CP
connector temperatures.
R
E
FLOW
TEM
P
(
C)
0
50
100
150
200
250
300
Preheat zo ne
max 4
o Cs -1
Soak zo ne
30-240s
Heat zone
max 4
o Cs -1
Peak Temp 235 o C
Co oling
zone
1-4
o Cs -1
T
lim
above
205 o C
REFLOW TIME (S)
Figure 22. Reflow Profile for Tin/Lead (Sn/Pb)
process
M
AX TE
M
P
S
O
LD
ER (
C)
200
205
210
215
220
225
230
235
240
0 10 20 30 40 50 60
Figure 23. Time Limit Curve Above 205
o
C for
Tin/Lead (Sn/Pb) process
Lead Free Soldering
The –Z version of the EVW020A0A modules are lead-
free (Pb-free) and RoHS compliant and are both
forward and backward compatible in a Pb-free and a
SnPb 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 Figure 23.
MSL Rating
The EVW020A0A modules have a MSL rating of 2.
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.