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Thyristors
Application Note
Application Note
■ Heatsink
A larger contact area between the device and the heatsink is required for
more effective heat radiation. To ensure a larger contact area, minimize
mounting holes. And select a heatsink with a surface smooth enough and
free from burrs and slivers.
■ Soldering Temperature
In general, the device mounted on a printed circuit board is subjected to
high temperatures from flow solder in a solder bath, or, from a soldering
iron at hand soldering.
The testing method and test conditions (JIS-C-7021 standards) for a
device’s heat resistance to soldering are:
At a distance of 1.5mm from the device's main body, apply 260°C for 10
seconds, and 350°C for 3 seconds.
Please observe these limits and finish soldering in as short a time as
possible.
Since reliability can be affected adversely by improper storage environ-
ment or handling methods during Characteristic tests, please observe the
following cautions.
Since reliability can be affected adversely by improper storage environ-
ment or handling methods during Characteristic tests, please observe the
following cautions.
■ Cautions for Storage
●Ensure that storage conditions comply with the normal temperature (5 to
35°C) and the normal relative humidity (around 40 to 75%), and avoid
storage locations that experience high temperature and humidity, or
extreme changes in temperature or humidity.
●Avoid locations where dust or harmful gases are present, and avoid
direct sunlight.
●Reinspect the devices for rust in leads and solderability after stored for a
long time.
■
Cautions for Characteristic Tests and Handling
On characteristics test at incoming inspection, etc, take good care to avoid
the surge voltages from the test equipment, the short circuit at terminals,
or the wrong connection.
■ Silicone Grease
When using a heatsink, please coat thinly and evenly the back surface of
the device and both surfaces of the insulating plate with silicone grease to
lower the thermal resistance between the device and the heatsink.
Please select proper silicone grease carefully since the oil in some grease
products may penetrate the device and result in an extremely short device
life.
Recommended Silicone Grease
•G-746 (Shin-Etsu Chemical)
• YG6260 (Momentive Performance Materials Inc.)
• SC102 (Dow Corning Toray Silicone)
■ Mounting Torque
When mounting torque is insufficient, thermal resistance increases, and so
heat radiation effect is decreased. When the torque is excessive, the
screw may be broken, the heatsink may be deformed, and the device
frame may be distorted, resulting in the device damage. Recommended
mounting torque per package is as follows:
● Mounting Torque Table
*
When the surface of a heatsink where Full Mold package is to be
mounted is not flat due to the burred metal bracket for screwing around
the mounting hole of the heatsink, the resin of the package might be
cracked even if the torque is lower than the recommended value.
*
When a screw is fastened with an air driver for the Full Mold package, a
large impact is generated at the time of stop, and the resin may crack
even if the torque is lower than the recommended value. An electric
driver, therefore, should be used instead of an air driver.
Package Screw Torque
TO-220 (MT-25) 0.490 to 0.686 N•m (5 to 7kgf•cm)
TO-220F (FM20)
TO-3P (MT-100) 0.686 to 0.882 N•m (7 to 9kgf•cm)
TO-3PF (FM100)
SIP with Fin (SLA) 0.588 to 0.784 N•m (6 to 8kgf•cm)
3 Thyristors