Leadframe and method of making the same
AssigneeChang Wah Technology Co., Ltd.
InventorChia-Neng HUANG
Life of this patent
Estimating the term…
Abstract
A leadframe includes first and second surfaces, a plurality of leads, and a hole-defining wall unit including a plurality of first-hole defining walls each defining a first through hole and a plurality of second-hole defining walls each defining a second through hole. Each of the first and second through holes is formed between two adjacent ones of the leads. Each of the first hole-defining walls has top and bottom edges respectively forming arcuate and burr regions with the first and surfaces at junctions therebetween. Each of the second hole-defining walls has top and bottom edges respectively forming burr and arcuate regions with the first and second surfaces at junctions therebetween.
Claims12
A leadframe, comprising:
- a first surface;
- a second surface opposite to said first surface;
- a lead unit including a plurality of leads each having a lead top surface and a lead bottom surface opposite to said lead top surface, said lead top surfaces of said leads cooperatively defining said first surface, said lead bottom surfaces of said leads cooperatively defining said second surface;
- and
- a hole-defining wall unit including a plurality of first hole-defining wall groups each having at least one first hole-defining wall and a plurality of second hole-defining wall groups each having at least one second hole-defining wall, each of said first hole-defining walls extending from said first surface to said second surface and surroundingly defining a first through hole, each of said second hole-defining walls extending from said first surface to said second surface and surroundingly defining a second through hole,
- wherein said first and second hole-defining wall groups are alternately disposed in said lead unit, each of said first through holes defined by said first hole-defining walls of said first hole-defining wall groups and said second through holes defined by said second hole-defining walls of said second hole-defining wall groups being formed between two adjacent ones of said leads;
- wherein said at least one first hole-defining wall of each of said first hole-defining wall groups has a first top edge connected to said first surface and a first bottom edge opposite to said first top edge and connected to said second surface, said first top edge and said first surface cooperatively forming an arcuate region at a first junction therebetween, said first bottom edge and said second surface cooperatively forming a burr region at a second junction therebetween, said burr region protruding from said second surface;
- and
- wherein said at least one second hole-defining wall of each of said second hole-defining wall groups has a second top edge connected to said first surface and a second bottom edge opposite to said second top edge and connected to said second surface, said second top edge and said first surface cooperatively forming a burr region at a third junction therebetween, said burr region protruding from said first surface, said second bottom edge and said second surface cooperatively forming an arcuate region at a fourth junction therebetween.
A method of making a leadframe, comprising:
- providing a substrate having an upper surface and a bottom surface opposite to the upper surface, the upper and bottom surfaces of the substrate being configured to serve as first and second surfaces of said leadframe;
- punching the substrate in a first direction from the upper surface to the bottom surface so as to form a portion of a lead unit including a plurality of leads;
- and punching the substrate in a second direction from the bottom surface to the upper surface so as to form a remainder of the lead unit.
Dependencies are inferred from the claim text.