AMIS-30660 High Speed CAN Transceiver
Data Sheet
Figure 9 – Common-mode voltage peaks (see measurement setup Fig. 8.)
Soldering
If wave soldering is used the following conditions must be
observed for optimal results:
Introduction to soldering surface mount packages
• Use a double-wave soldering method comprising a
turbulent wave with high upward pressure followed by a
smooth laminar wave.
This text gives a very brief insight to a complex technology.
A more in-depth account of soldering ICs can be found in
our “Data Handbook IC26; Integrated Circuit Packages”
(document order number 9398 652 90011).
• For packages with leads on two sides and a pitch (e):
– larger than or equal to 1.27mm, the footprint
longitudinal axis is preferred to be parallel to the
transport direction of the printed-circuit board;
– smaller than 1.27mm, the footprint longitudinal axis
must be parallel to the transport direction of the printed-
circuit board.The footprint must incorporate solder thieves
at the downstream end.
There is no soldering method that is ideal for all surface
mount IC packages. Wave soldering is not always suitable
for surface mount ICs, or for printed-circuit boards with high
population densities. In these situations reflow soldering is
often used.
• For packages with leads on four sides, the footprint must
be placed at a 45º angle to the transport direction of the
printed-circuit board. The footprint must incorporate
solder thieves downstream and at the side corners.
Reflow soldering
Reflow soldering requires solder paste (a suspension of fine
solder particles, flux and binding agent) to be applied to the
printed-circuit board by screen printing, stencilling or
pressure-syringe dispensing before package placement.
During placement and before soldering, the package must
be fixed with a droplet of adhesive. The adhesive can be
applied by screen printing, pin transfer or syringe
dispensing. The package can be soldered after the adhesive
is cured.
Several methods exist for reflowing; for example,
infrared/convection heating in a conveyor type oven.
Throughput times (preheating, soldering and cooling) vary
between 100 and 200 seconds depending on heating
method.
Typical dwell time is 4 seconds at 250°C. A mildly-activated
flux will eliminate the need for removal of corrosive residues
in most applications.
Typical reflow peak temperatures range from 215 to 250°C.
The top-surface temperature of the packages should
preferably be kept below 230 °C.
Manual soldering
Fix the component by first soldering two diagonally-
opposite end leads. Use a low voltage (24 V or less)
soldering iron applied to the flat part of the lead. Contact
time must be limited to 10 seconds at up to 300°C.
When using a dedicated tool, all other leads can be
soldered in one operation within 2 to 5 seconds between
270 and 320°C.
Wave soldering
Conventional single wave soldering is not recommended for
surface mount devices (SMDs) or printed-circuit boards with
a high component density, as solder bridging and non-
wetting can present major problems.
To overcome these problems the double-wave soldering
method was specifically developed.
AMI Semiconductor
10
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