AMIS30512 ON Semiconductor, AMIS30512 Datasheet - Page 29

• Manufacturer Part Number: AMIS30512
• Description: Micro-stepping Motor Driver
• Manufacturer: ON Semiconductor

Introduction to Soldering Surface Mount Packages
technology. A more in-depth account of soldering ICs can be
found in the AMIS “Data Handbook IC26; Integrated
Circuit Packages” (document order number 9398 652
90011). 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
(PCB) with high population densities. In these situations
re-flow soldering is often used.
Re−flow Soldering
fine solder particles, flux and binding agent) to be applied to
the PCB by screen printing, stencilling or pressure-syringe
dispensing before package placement. Several methods
exist for re-flowing; for example, infrared/convection
heating in a conveyor type oven.
vary between 100 and 200 seconds depending on the heating
method. Typical re-flow peak temperatures range from 215
to 260°C. The top-surface temperature of the packages
should preferably be kept below 230°C.
Wave Soldering
for surface mount devices (SMDs) or PCBs 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.
observed for optimal results:
7. All surface mount (SMD) packages are moisture sensitive. Depending upon the moisture content, the maximum temperature (with respect
8. These packages are not suitable for wave soldering as a solder joint between the PCB and heatsink (at bottom version) can not be achieved,
9. If wave soldering is considered, then the package must be placed at a 45° angle to the solder wave direction. The package footprint must
10. Wave soldering is only suitable for LQFP, TQFP and QFP packages with a pitch (e) equal to or larger than 0.8 mm; it is definitely not suitable
11. Wave soldering is only suitable for SSOP and TSSOP packages with a pitch (e) equal to or larger than 0.65 mm; it is definitely not suitable
Table 32. Soldering Process
BGA, SQFP
HLQFP, HSQFP, HSOP, HTSSOP, SMS
PLCC (Note 9) , SO, SOJ
LQFP, QFP, TQFP
SSOP, TSSOP, VSO
This text gives a very brief insight to a complex
Re-flow soldering requires solder paste (a suspension of
Throughput times (preheating, soldering and cooling)
Conventional single wave soldering is not recommended
If wave soldering is used the following conditions must be
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.”
and as solder may stick to the heatsink (on top version).
incorporate solder thieves downstream and at the side corners.
for packages with a pitch (e) equal to or smaller than 0.65 mm.
for packages with a pitch (e) equal to or smaller than 0.5 mm.
Package
Not recommended (Notes 9 and 10)
http://onsemi.com
Not recommended (Note 11)
Soldering
Not suitable (Note 8)
29
Not suitable
Suitable
Wave
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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. Typical dwell time is four seconds at 250°C. A
mildly-activated flux will eliminate the need for removal of
corrosive residues in most applications.
Manual Soldering
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.
soldered in one operation within two to five seconds
between 270 and 320°C.
During placement and before soldering, the package must
Fix the component by first soldering two diagonally-
When using a dedicated tool, all other leads can be
Use a double-wave soldering method comprising a
turbulent wave with high upward pressure followed by
a smooth laminar wave.
For packages with leads on two sides and a pitch (e):
For packages with leads on four sides, the footprint
must be placed at a 45° angle to the transport direction
of the PCB. The footprint must incorporate solder
thieves downstream and at the side corners.
1. Larger than or equal to 1.27 mm, the footprint
2. Smaller than 1.27 mm, the footprint longitudinal
longitudinal axis is preferred to be parallel to the
transport direction of the PCB;
axis must be parallel to the transport direction of
the PCB. The footprint must incorporate solder
thieves at the downstream end.
Soldering Method
Re-flow (Note 7)
Suitable
Suitable
Suitable
Suitable
Suitable