Environmental conditions for storage of surface assembly components:
Ambient temperature: stock temperature <40℃.
Production site temperature <30℃.
Ambient humidity : < RH60%.
Ambient atmosphere: there should be no toxic gases such as sulfur, chlorine and acid which can affect the welding performance in the storage and operating environment.
Anti - static measures: to meet the requirements of anti - static SMT components.
Storage cycle of components: the inventory time shall not exceed 2 years from the production date of the components manufacturer; The inventory time after the purchase of the complete machine factory user is generally not more than 1 year; If it is a whole machine factory with a relatively humid natural environment, SMT components should be used within 3 months after purchase, and appropriate moisture-proof measures should be taken in the storage place and the packaging of components.
SMD devices with moisture-proof requirements. It must be used within 72 hours after opening, no more than a week. If it can not be used up, it should be stored in the RH20% drying oven, and the damp SMD devices should be dried and dehumidified according to the regulations.
SMD (SOP, SJ, LCC and QFP, etc.) with plastic tube packaging, its packaging tube is not high temperature resistance, can not be directly put into the oven baking, should be separately placed in the metal tube or metal plate to bake.
QFP packaging plastic tray has two kinds of high temperature and high temperature. High temperature resistant (note TMAX =135℃, 150℃ or MAX180 ℃, etc.) can be directly put into the oven for baking; High temperature resistant can not be directly into the oven to bake, in order to prevent accidents, should be placed in the metal plate for baking. Pins should be prevented from being damaged during rotation, so as not to destroy their coplanar properties.
Transportation, sorting, inspection or manual stacking:
If the staff needs to take the SMD device, they should wear anti-static wristband, try to use the suction pen operation, and pay special attention to avoid touching the pins of SOP, QFP and other devices, to prevent pin warping deformation.
Saving method of remaining SMD:
Equipped with special low temperature and low humidity storage box. Store the SMD temporarily unused after opening or with the feeder in the box. However, it is more expensive to equip a large special low temperature and low humidity storage box.
Use the original package in good condition. As long as the bag is not damaged and the desiccant inside is good (all the black circles on the humidity indicator card are blue, no pink), you can still put the unused SMD back into the bag and seal it with tape.