FKI10198

FKI10198-DS Rev.1.2

SANKEN ELECTRIC CO.,LTD.

5

Jan. 20, 2014

OPERATING PRECAUTIONS

In the case that you use Sanken products or design your products by using Sanken products, the reliability largely

depends on the degree of derating to be made to the rated values. Derating may be interpreted as a case that an operation

range is set by derating the load from each rated value or surge voltage or noise is considered for derating in order to

assure or improve the reliability. In general, derating factors include electric stresses such as electric voltage, electric

current, electric power etc., environmental stresses such as ambient temperature, humidity etc. and thermal stress caused

due to self-heating of semiconductor products. For these stresses, instantaneous values, maximum values and minimum

values must be taken into consideration. In addition, it should be noted that since power devices or IC’s including power

devices have large self-heating value, the degree of derating of junction temperature affects the reliability significantly.

Because reliability can be affected adversely by improper storage environments and handling methods, please

observe the following cautions.

Cautions for Storage

 Ensure that storage conditions comply with the standard temperature (5 to 35°C) and the standard relative humidity

(around 40 to 75%); avoid storage locations that experience extreme changes in temperature or humidity.

 Avoid locations where dust or harmful gases are present and avoid direct sunlight.

 Reinspect for rust on leads and solderability of the products that have been stored for a long time.

Cautions for Testing and Handling

When tests are carried out during inspection testing and other standard test periods, protect the products from power

surges from the testing device, shorts between the product pins, and wrong connections. Ensure all test parameters are

within the ratings specified by Sanken for the products.

Remarks About Using Silicone Grease with a Heatsink

 When silicone grease is used in mounting the products on a heatsink, it shall be applied evenly and thinly. If more

silicone grease than required is applied, it may produce excess stress.

 Volatile-type silicone greases may crack after long periods of time, resulting in reduced heat radiation effect.

Silicone greases with low consistency (hard grease) may cause cracks in the mold resin when screwing the

products to a heatsink.

Our recommended silicone greases for heat radiation purposes, which will not cause any adverse effect on the

product life, are indicated below:

Type

Suppliers

G746

Shin-Etsu Chemical Co., Ltd.

YG6260 Momentive Performance Materials Inc.

SC102

Dow Corning Toray Co., Ltd.

Cautions for Mounting to a Heatsink

 When the flatness around the screw hole is insufficient, such as when mounting the products to a heatsink that has

an extruded (burred) screw hole, the products can be damaged, even with a lower than recommended screw torque.

For mounting the products, the mounting surface flatness should be 0.05mm or less.

 Please select suitable screws for the product shape. Do not use a flat-head machine screw because of the stress to

the products. Self-tapping screws are not recommended. When using self-tapping screws, the screw may enter the

hole diagonally, not vertically, depending on the conditions of hole before threading or the work situation. That

may stress the products and may cause failures.

 Recommended screw torque:

Package

Recommended Screw Torque

TO-220, TO-220F

0.490 to 0.686 N・m

(5 to 7 kgf・cm)

TO-3P, TO-3PF, TO-247

0.686 to 0.882 N・m

(7 to 9 kgf・cm)

SLA

0.588 to 0.784 N・m

(6 to 8 kgf・cm)

 For tightening screws, if a tightening tool (such as a driver) hits the products, the package may crack, and internal

stress fractures may occur, which shorten the lifetime of the electrical elements and can cause catastrophic failure.

Tightening with an air driver makes a substantial impact. In addition, a screw torque higher than the set torque can

be applied and the package may be damaged. Therefore, an electric driver is recommended.

When the package is tightened at two or more places, first pre-tighten with a lower torque at all places, then tighten

with the specified torque. When using a power driver, torque control is mandatory.

 Please pay special attention about the slack of the press mold. In case that the hole diameter of the heatsink is less

than 4 mm, it may cause the resin crack at tightening.