Lead frame

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Lead frames are the metal structures inside a chip package that carry signals from the die to the outside.

Leadframe for a QFP package

The die inside the package is typically glued to the lead frame, and then bond wires attach the die pads to the leads. In the last stage of the manufacturing process, the lead frame is moulded in a plastic case, and outside of the lead frame is cut-off, separating all leads.

Manufacturing[edit]

Lead frames are manufactured by removing material from a flat plate of copper or copper-alloy. Two processes used for this are etching (suitable for high density of leads), or stamping (suitable for low density of leads).[1]

Uses[edit]

Amongst others, leadframes are used to manufacture a quad flat no-leads package (QFN), a quad flat package (QFP), or a dual in-line package (DIP).

See also[edit]

References[edit]