PCBA board will occasionally be repaired, repair is also a very important link, once there is a slight error, may directly lead to the board scrap can not be used. Today brings PCBA repair requirements ~ let’s have a look!
First,baking requirements
All new components to be installed must be baked and dehumidified according to the humidity sensitive level and storage conditions of the components and the requirements in the Usage Specification for Moisture Sensitive Components.
If the repair process needs to be heated to more than 110 ° C, or there are other moisture-sensitive components within 5mm around the repair area, it must be baked to remove moisture according to the humidity sensitivity level and storage conditions of the components, and in accordance with the relevant requirements of the Code for the Use of moisture-Sensitive Components.
For the moisture sensitive components that need to be reused after repair, if the repair process such as hot air reflux or infrared is used to heat the solder joints through the component package, the moisture removal process must be performed according to the humidity sensitive grade and storage conditions of the components and the relevant requirements in the Code for Use of Moisture Sensitive Components. For the repair process using manual ferrochrome heating solder joints, pre-baking can be avoided under the premise that the heating process is controlled.
Second, storage environment requirements after baking
If the storage conditions of the baked moisture sensitive components, PCBA, and unpacked new components to be replaced exceed the expiration date, you need to bake them again.
Third, the requirements of PCBA repair heating times
The total allowable rework heating of the component shall not exceed 4 times; The allowable rerepair heating times of new components shall not exceed 5 times; The number of reheating times allowed for the re-use components removed from the top is not more than 3 times.
Post time: Feb-19-2024