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Note
1. Plastic or metal protrusions of 0.25 mm maximum per side are not included.
REFERENCES
OUTLINE EUROPEAN
ISSUE DATE
VERSION PROJECTION
IEC JEDEC EIAJ
95-02-04
SOT307-2
97-08-01
1999 Apr 08 34
c
Philips Semiconductors Product specification
Speech and handsfree IC with auxiliary
TEA1099H
inputs/outputs and analog multiplexer
If wave soldering is used the following conditions must be
SOLDERING
observed for optimal results:
Introduction to soldering surface mount packages
" Use a double-wave soldering method comprising a
This text gives a very brief insight to a complex technology.
turbulent wave with high upward pressure followed by a
A more in-depth account of soldering ICs can be found in
smooth laminar wave.
our  Data Handbook IC26; Integrated Circuit Packages
" For packages with leads on two sides and a pitch (e):
(document order number 9398 652 90011).
 larger than or equal to 1.27 mm, the footprint
There is no soldering method that is ideal for all surface
longitudinal axis is preferred to be parallel to the
mount IC packages. Wave soldering is not always suitable
transport direction of the printed-circuit board;
for surface mount ICs, or for printed-circuit boards with
 smaller than 1.27 mm, the footprint longitudinal axis
high population densities. In these situations reflow
must be parallel to the transport direction of the
soldering is often used.
printed-circuit board.
The footprint must incorporate solder thieves at the
Reflow soldering
downstream end.
Reflow soldering requires solder paste (a suspension of
" For packages with leads on four sides, the footprint must
fine solder particles, flux and binding agent) to be applied
be placed at a 45° angle to the transport direction of the
to the printed-circuit board by screen printing, stencilling or
printed-circuit board. The footprint must incorporate
pressure-syringe dispensing before package placement.
solder thieves downstream and at the side corners.
Several methods exist for reflowing; for example,
During placement and before soldering, the package must
infrared/convection heating in a conveyor type oven.
be fixed with a droplet of adhesive. The adhesive can be
Throughput times (preheating, soldering and cooling) vary
applied by screen printing, pin transfer or syringe
between 100 and 200 seconds depending on heating
dispensing. The package can be soldered after the
method.
adhesive is cured.
Typical reflow peak temperatures range from
Typical dwell time is 4 seconds at 250 °C.
215 to 250 °C. The top-surface temperature of the
A mildly-activated flux will eliminate the need for removal
packages should preferable be kept below 230 °C.
of corrosive residues in most applications.
Wave soldering
Manual soldering
Conventional single wave soldering is not recommended
Fix the component by first soldering two
for surface mount devices (SMDs) or printed-circuit boards
diagonally-opposite end leads. Use a low voltage (24 V or
with a high component density, as solder bridging and
less) soldering iron applied to the flat part of the lead.
non-wetting can present major problems.
Contact time must be limited to 10 seconds at up to
To overcome these problems the double-wave soldering
300 °C.
method was specifically developed.
When using a dedicated tool, all other leads can be
soldered in one operation within 2 to 5 seconds between
270 and 320 °C.
1999 Apr 08 35
Philips Semiconductors Product specification
Speech and handsfree IC with auxiliary
TEA1099H
inputs/outputs and analog multiplexer
Suitability of surface mount IC packages for wave and reflow soldering methods
SOLDERING METHOD
PACKAGE
WAVE REFLOW(1)
BGA, SQFP not suitable suitable
HLQFP, HSQFP, HSOP, HTSSOP, SMS not suitable(2) suitable
PLCC(3), SO, SOJ suitable suitable
LQFP, QFP, TQFP not recommended(3)(4) suitable
SSOP, TSSOP, VSO not recommended(5) suitable
Notes
1. All surface mount (SMD) packages are moisture sensitive. Depending upon the moisture content, the maximum
temperature (with respect to time) and body size of the package, there is a risk that internal or external package
cracks may occur due to vaporization of the moisture in them (the so called popcorn effect). For details, refer to the
Drypack information in the  Data Handbook IC26; Integrated Circuit Packages; Section: Packing Methods .
2. These packages are not suitable for wave soldering as a solder joint between the printed-circuit board and heatsink
(at bottom version) can not be achieved, and as solder may stick to the heatsink (on top version).
3. If wave soldering is considered, then the package must be placed at a 45° angle to the solder wave direction.
The package footprint must incorporate solder thieves downstream and at the side corners.
4. Wave soldering is only suitable for LQFP, TQFP and QFP packages with a pitch (e) equal to or larger than 0.8 mm; [ Pobierz całość w formacie PDF ]