US5663593A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Ball grid array package with lead frame
Assignee: National Semiconductor Corp
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Filing: 1995-10-17
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Granted: 1997-09-02
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Expires: 2015-10-17
Abstract
Abstract A ball grid array (BGA) package incorporates a lead frame which includes a die attach pad and a plurality of leads radiating away from the die attach pad. A die is mounted on the die attach pad and electrically connected to the leads by wire bonding. A non-conductive solder mask or tape is applied to the lead frame which defines a number of selectively positioned vias (openings). A molded plastic casing or a cap is positioned over the die, wiring and lead frame to encapsulate the package. Solder balls or columns are attached to selected leads of the lead frame through the vias.
Inventors
- 👤 Shahram Mostafazadeh
- 👤 Joseph O. Smith
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 06:28
CPC Classifications
H; H10; H10W; H10W70/00; H10W70/40; H10W70/421; H10W74/00; H10W74/10; H10W74/111; H10W72/00; H10W72/30; H10W72/381; H10W72/50; H10W72/551; H10W72/552; H10W72/5522; H10W72/851; H10W72/874; H10W72/884; H10W90/00; H10W90/701; H10W90/731; H10W90/734; H10W90/751; H10W90/754; H10W90/756
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
219 words
An electrical device comprising: a flat lead frame including: a centrally-located die attach pad, a plurality of elongated leads which are electrically isolated from the die attach pad and extend in a radial direction away from the die attach pad, and a tie bar attached to the die attach pad and extending in a radial direction away from the die attach pad, the tie bar being positioned between two of the plurality of leads, wherein the die attach pad, the plurality of elongated leads and the tie bar are located in a common plane, and wherein the lead frame has opposing first and second surfaces; an integrated circuit chip mounted on the die attach pad on the first surface of the lead frame, the integrated circuit chip including a plurality of die bond pads; a non-conductive coating formed on the second surface of the lead frame, the non-conductive coating defining a plurality of openings exposing selected portions the plurality of leads; and a plurality of conductors, each of the plurality of conductors being electrically connected through one of the openings in the non-conductive coating to one of the plurality of leads; wherein each of the die bond pads is electrically connected with a selected one of the plurality of leads; and wherein the non-conductive coating is a solder mask.
Claim 2
Dependent Claim
219 words
An electrical device comprising: a flat lead frame including: a centrally-located die attach pad, a plurality of elongated leads which are electrically isolated from the die attach pad and extend in a radial direction away from the die attach pad, and a tie bar attached to the die attach pad and extending in a radial direction away from the die attach pad, the tie bar being positioned between two of the plurality of leads, wherein the die attach pad, the plurality of elongated leads and the tie bar are located in a common plane, and wherein the lead frame has opposing first and second surfaces; an integrated circuit chip mounted on the die attach pad on the first surface of the lead frame, the integrated circuit chip including a plurality of die bond pads; a non-conductive coating formed on the second surface of the lead frame, the non-conductive coating defining a plurality of openings exposing selected portions the plurality of leads; and a plurality of conductors, each of the plurality of conductors being electrically connected through one of the openings in the non-conductive coating to one of the plurality of leads; wherein each of the die bond pads is electrically connected with a selected one of the plurality of leads; and wherein the non-conductive coating is a solder mask.
Claim 3
Dependent Claim
34 words
The electrical device of claim 1, further comprising a plurality of wires, each of the plurality of wires connecting one of the die bond pads with a selected one of the plurality of leads.
Claim 4
Dependent Claim
19 words
The electrical device of claim 1, further comprising a cover formed over the first surface of the lead frame.
Claim 5
Dependent Claim
12 words
The electrical device of claim 3, wherein the cover comprises molded plastic.
Claim 6
Dependent Claim
12 words
The electrical device of claim 3, wherein the cover comprises a cap.
Claim 7
Dependent Claim
12 words
The electrical device of claim 1, wherein the conductors are solder balls.
Claim 8
Dependent Claim
12 words
The electrical device of claim 1, wherein the conductors are solder columns.
Claim 9
Dependent Claim
168 words
An electrical device comprising: a flat lead frame formed from a single metal sheet, the lead frame including: a die attach pad, a plurality of elongated leads which are electrically isolated from the die attach pad, and a tie bar attached to the die attach pad, wherein the lead frame has opposing first and second surfaces; an integrated circuit chip mounted on the die attach pad on the first surface of the lead frame, the integrated circuit chip including a plurality of die bond pads; a solder mask deposited on the second surface of the lead frame, the solder mask defining a plurality of openings exposing selected portions the plurality of leads; a plurality of conductors, each of the plurality of conductors being electrically connected through one of the openings in the solder mask to one of the plurality of leads; and a plurality of wires, each of the plurality of wires connecting one of the die bond pads with a selected one of the plurality of leads.
Claim 10
Dependent Claim
168 words
An electrical device comprising: a flat lead frame formed from a single metal sheet, the lead frame including: a die attach pad, a plurality of elongated leads which are electrically isolated from the die attach pad, and a tie bar attached to the die attach pad, wherein the lead frame has opposing first and second surfaces; an integrated circuit chip mounted on the die attach pad on the first surface of the lead frame, the integrated circuit chip including a plurality of die bond pads; a solder mask deposited on the second surface of the lead frame, the solder mask defining a plurality of openings exposing selected portions the plurality of leads; a plurality of conductors, each of the plurality of conductors being electrically connected through one of the openings in the solder mask to one of the plurality of leads; and a plurality of wires, each of the plurality of wires connecting one of the die bond pads with a selected one of the plurality of leads.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2000-09-01 | 2001-03-03 | 2001-09-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-09-01 | 2005-03-03 | 2005-09-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-09-01 | 2009-03-03 | 2009-09-02 | $7700.00 | Window Closed / Lapsed |