QFP (Quad Flat Package) grounding welding plate

Abstract

The invention belongs to the QFP (Quad Flat Package) field and particularly relates to a QFP grounding welding plate. The QFP grounding welding plate comprises a heat radiating hole and a matrix arrangement hole, wherein the heat radiating hole is positioned in the middle of the grounding welding plate; and the matrix arrangement hole is positioned on the grounding welding plate and bypasses the heat radiating hole. The thickness of the periphery of the grounding welding plate is larger than that of the middle part of the grounding welding plate; solder paste is filled in the matrix arrangement hole; the thickness of the middle part of the grounding welding plate is 0.15-0.18 millimeter; the thickness of the periphery of the grounding welding plate is 0.3-0.4 millimeter; and the matrix arrangement hole is square or circular or triangular. The QFP grounding welding plate has the beneficial effects that as the heat radiating hole positioned in the middle of the grounding welding plate, the grounding welding plate has good heat radiation; and meanwhile, as the periphery of the grounding welding plate is thickened to 0.3-0.4 millimeter, a proper amount of solder paste is moistened and diffused to the whole grounding welding plate and does not generate solder balls, so that the grounding requirements are satisfied.

Description

Technical field [0001] The invention belongs to the field of QFP packaging, and particularly relates to a QFP grounding pad. Background technique [0002] QFP (quad flat package), which is a four-side pin flat package, is one of surface mount packaging technology (SMT). The pins are drawn from four sides in a seagull wing (L) shape. The base material is ceramic, metal and Three kinds of plastic. Plastic QFP is the most popular multi-pin LSI package. It is used not only for digital logic LSI circuits such as microprocessors and gate displays, but also for analog LSI circuits such as VTR signal processing and audio signal processing. It is easy to operate and suitable for high-frequency applications. . However, in the QFP packaging process, there is an unequal distance between the solder pin plane and the ground pad plane of about 0.15mm, which can easily lead to poor grounding and I / O open circuit during soldering. For some high-power QFPs, the amount of tin on the ground pad i...

AI Technical Summary

Problems solved by technology

However, in the QFP packaging process, there is a distance between the plane of the solder pin and the plane of the ground pad of about 0.15mm, which may easily lead to poor grounding and I / O open circuit during soldering.

For some high-power QFPs, the amount of tin on the ground pad is often insufficient, and the problem is manifested as overflow tin on the ground, floating height, and large-area air bubbles lead to insufficient wetting area, which affects conductivity

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