Special fixture for gold removal and tin coating for QFN encapsulated components, and method for gold removal and tin coating

Abstract

The invention discloses a special fixture for gold removal and tin coating for QFN encapsulated components, and a method for gold removal and tin coating. The special fixture is composed of a cross brace, a rail seat, a bottom frame, an upper supporting plate, a component supporting plate, a fastener, a press sheet, a long screw rod, a short screw rod, a component screw rod, a bearing seat, a cotter pin and a wheel shaft, wherein the cross brace and the rail seat form a guide rail; the wheel shaft, the bearing seat and the bottom frame are assembled into a lower supporting mechanism capable of moving on the guide rail; the upper supporting plate is fixed on the bottom frame, the component supporting plate is placed in a groove of the upper supporting plate, and the components are placed in installation hole positions of the component supporting plate; and the guide rail of the special fixture is horizontally placed on the table surface of a repair workbench for through-hole components, and the lower supporting mechanism is moved to enable bonding pads of the QFN components to complete gold removal and tin coating through the wave crests of a spewing molten tin-lead alloy. The method disclosed by the invention is high in applicability, and can be used for gold removal and tin coating for all the QFN components on the repair workbench for through-hole components.

Description

technical field [0001] The invention relates to a special jig for removing gold and tin from QFN packaged components and a method for removing gold and tin The method of degolding and tinning QFN devices on the rework bench is suitable for electronic assembly. Background technique [0002] Components with gold-plated pads are prone to "gold brittleness" during the process of soldering and assembling to printed boards, which seriously affects the reliability and service life of the product. Therefore, when high reliability and long life are required In the process of electronic assembly, such pads must be degolded and tinned. Compared with FP / QFP chips, etc., due to the special structure of QFN devices and other non-lead surface mount components, at present, most of them rely on the operator's manual soldering iron to remove gold and tin, which depends heavily on the operator's skill level, the product consistency is poor, and there are Pad bridging, overheating damage and ...

AI Technical Summary

Problems solved by technology

Compared with FP / QFP chips, etc., due to the special structure of QFN devices and other non-lead surface mount components, at present, most of them rely on operators to remove gold and tin with electric soldering irons, which rely heavily on the skill level of operators. The product consistency is poor, and there are Pad bridging, overheating damage and other risks

Images