Lead free soldering, Pb-free reflow profile, Msl rating – GE Industrial Solutions EQW012-020-023-025 Series User Manual

Page 23: Storage and handling, Post solder cleaning and drying considerations

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Data Sheet

October 5, 2013

EQW012/020/023/025 Series, Eighth-Brick Power Modules:

36 - 75Vdc Input; 1.2Vdc to 5Vdc Output; 12A to 25A Output

LINEAGE

POWER

23

Surface Mount Information (continued)

Tin Lead Soldering

The recommended linear reflow profile using Sn/Pb
solder is shown in Figure 49 and 50. For reliable
soldering the solder reflow profile should be
established by accurately measuring the modules CP
connector temperatures.

R

E

FL

O

W

TE

M

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 49. Recommended Reflow Profile for Sn/Pb
Solder.

M

A

X

TEM

P

SOLDER (

C)

200

205

210

215

220

225

230

235

240

0

10

20

30

40

50

60

TIME LIMIT (S)

Figure 50. Time Limit, T

lim

, Curve Above 205

o

C

Reflow .

Lead Free Soldering

The –Z version SMT modules of EQW series are
lead-free (Pb-free) and RoHS compliant and are
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. D
(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. 51.

Figure 51. Recommended linear reflow profile
using Sn/Ag/Cu solder.

MSL Rating

The EQW series SMT 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.

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 Lineage Power Board
Mounted Power Modules: Soldering and Cleaning

Application Note (AN04-001).

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