METHOD FOR DESIGNING MOISTURE-PROOF STRUCTURE OF LED SMD HOLDER

摘要

A method for designing a moisture-proof structure of an LED SMD holder. The moisture-proof structure comprises: a metal holder (1); a reflector cup (2) covering the metal holder; bonding wires (3); LED chips (4) fixed to the metal holder; plastic (5); and a packaging adhesive used for sealing and protecting the LED chips. The metal holder comprises metal leads (11) embedded in the reflector cup and metal pins (12) exposed out of the reflector cup and used as positive and negative electrodes of the metal holder. Area minimization of the metal leads and maximization of bonding of the plastic and the packaging adhesive are guaranteed on the premise of reserving necessary setting areas for the LED chips and welding areas for the bonding wires. The design of the metal leads of the conventional LED holder is changed, the area of the metal leads is reduced to expand the bonding area of the reflector cup and the packaging adhesive, and further the bonding force of the reflector cup and the packaging adhesive is increased, moisture entering the reflector cup is reduced, moisture proofing is achieved, and accordingly the reliability and service life of an LED are improved.