Document Number: 002-10635 Rev. *I
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159 of 325
S6J3310/20/30/40 Series
8.1.2
Precautions for Package Mounting
Package mounting may be either lead insertion type or surface mount type. In either case, for heat resistance during soldering, you
should only mount under Cypress’s recommended conditions. For detailed information about mount conditions, contact your sales
representative.
Lead Insertion Type
Mounting of lead insertion type packages onto printed circuit boards may be done by two methods: direct soldering on the board,
or mounting by using a socket.
Direct mounting onto boards normally involves processes for inserting leads into through-holes on the board and using the flow
soldering (wave soldering) method of applying liquid solder. In this case, the soldering process usually causes leads to be
subjected to thermal stress in excess of the absolute ratings for storage temperature. Mounting processes should conform to
Cypress recommended mounting conditions.
If socket mounting is used, differences in surface treatment of the socket contacts and IC lead surfaces can lead to contact
deterioration after long periods. For this reason it is recommended that the surface treatment of socket contacts and IC leads be
verified before mounting.
Surface Mount Type
Surface mount packaging has longer and thinner leads than lead-insertion packaging, and therefore leads are more easily
deformed or bent. The use of packages with higher pin counts and narrower pin pitch results in increased susceptibility to open
connections caused by deformed pins, or shorting due to solder bridges.
You must use appropriate mounting techniques. Cypress recommends the solder reflow method, and has established a ranking of
mounting conditions for each product. Users are advised to mount packages in accordance with Cypress ranking of recommended
conditions.
Lead-Free Packaging
CAUTION: When ball grid array (BGA) packages with Sn-Ag-Cu balls are mounted using Sn-Pb eutectic soldering, junction
strength may be reduced under some conditions of use.
Storage of Semiconductor Devices
Because plastic chip packages are formed from plastic resins, exposure to natural environmental conditions will cause absorption
of moisture. During mounting, the application of heat to a package that has absorbed moisture can cause surfaces to peel,
reducing moisture resistance and causing packages to crack. To prevent, do the following:
(1) Avoid exposure to rapid temperature changes, which cause moisture to condense inside the product. Store products in
locations where temperature changes are slight.
(2) Use dry boxes for product storage. Products should be stored below 70 % relative humidity, and at temperatures between 5 ˚C
and 30 ˚C. When you open Dry Package that recommends humidity 40 % to 70 % relative humidity.
(3) When necessary, Cypress packages semiconductor devices in highly moisture-resistant aluminum laminate bags, with a silica
gel desiccant. Devices should be sealed in their aluminum laminate bags for storage.
(4) Avoid storing packages where they are exposed to corrosive gases or high levels of dust.
Baking
Packages that have absorbed moisture may be de-moisturized by baking (heat drying). Follow the Cypress recommended
conditions for baking.
Condition: 125 ˚C/24 h
Static Electricity
Because semiconductor devices are particularly susceptible to damage by static electricity, you must take the following
precautions:
(1) Maintain relative humidity in the working environment between 40 % and 70 %.
Use of an apparatus for ion generation may be needed to remove electricity.
(2) Electrically ground all conveyors, solder vessels, soldering irons and peripheral equipment.
(3) Eliminate static body electricity by the use of rings or bracelets connected to ground through high resistance (on the level of 1
MΩ).
Wearing of conductive clothing and shoes, use of conductive floor mats and other measures to minimize shock loads is
recommended.
(4) Ground all fixtures and instruments, or protect with anti-static measures.
