SOT23 lead frame and packaging process flow thereof

Abstract

The invention discloses an SOT23 lead frame structure and a packaging process flow thereof. The SOT23 lead frame structure comprises a frame and a plurality of mounting units, wherein the mounting units are arranged on the frame in a manner of X rows and XY columns; a column of runners is arranged at an interval of N columns of mounting units; N is not smaller than 2; each mounting unit comprises an outer pin; the outer pins of two adjacent rows of mounting units are crosswire staggered with one another; a dam bar I is arranged between two adjacent outer pins of the same mounting unit; a dam bar II is arranged between the adjacent outer pins of two adjacent mounting units in the same row of mounting units; a dam bar III is arranged between the outer pins at the outermost sides of the mounting units at the left end and the right end in the same row of mounting units and the frame; and in trimming and forming processes, the dam bar I at one side is firstly cut, the dam bar I at the other side is cut and conveyed to a track of a forming part, and then the dam bar II and the dam bar III are cut off.

Description

Technical field [0001] The invention relates to an integrated circuit packaging lead frame, and in particular to an SOT23 lead frame and its packaging process. Background technique [0002] Chip packaging is a technology that packages integrated circuits with insulating plastic or ceramic materials. It not only plays the role of placing, fixing, sealing, protecting the chip and enhancing thermal conductivity, but also serves as a bridge between the internal world of the chip and the external circuit. Small outline transistor package (SOT23, SmallOutlineTransistor) is a commonly used small patch chip package. like figure 1 As shown, the SOT23 lead frame structure includes a frame A, a plurality of mounting units B and a flow channel C arranged on the frame. Each mounting unit includes a base island and pins arranged on the upper and lower sides of the base island. Each pin Including external pins and internal pins. In the traditional SOT23 lead frame structure, the external...

AI Technical Summary

Problems solved by technology

like figure 1 As shown, the SOT23 lead frame structure includes a frame A, a plurality of installation units B and flow channels C arranged on the frame, each installation unit includes a base island and pins arranged on the upper and lower sides of the base island, and each pin Including the outer pins and inner pins, in the traditional SOT23 lead frame structure, the outer pins of the two adjacent installation units are aligned up and down and spaced apart from each other, and the spaced parts are formed as middle ribs D, so that the outer pins The area of ​​the middle rib between the outer pins and the gap between two adjacent outer pins is wasted, so the utilization rate of the frame is low; and every other column of installation unit B is provided with a column of flow channels C, that is, when plastic sealing Only one product can be plastic-sealed at a time, so more runners C must be set on the frame A to meet the demand, and more runners C will occupy more area, thereby reducing the utilization rate of the frame and causing the mold compound low utilization

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