← Back to Patent Explorer
US5008615A Expired / Lapsed US ⏱️ 0.0 years remaining

Means and method for testing integrated circuits attached to a leadframe

Assignee: NXP USA Inc
•
Filing: 1989-11-03
•
Granted: 1991-04-16
•
Expires: 2009-11-03
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract Apparatus and method of testing integrated circuits after the leads have been trimmed and partially formed, but before the package has been removed from the leadframe. One stage of a progressive trim and form process is adapted to test the integrated circuits by providing a membrane test head positioned underneath the IC package, wherein the membrane test head is coupled to an external tester. After the leads are electrically separated from each other end from the leadframe, the leads are aligned to the membrane test head and an inflatable bladder, which is positioned underneath the membrane test head, is inflated to couple the membrane test head to the leads. In this manner, one or more integrated circuits can be tested while still attached to the leadframe.

Inventors

  • 👤 Hugh W. Littlebury

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-08 09:32
CPC Classifications
G; G01; G01R; G01R1/00; G01R1/02; G01R1/06; G01R1/04; G01R1/0408; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49117; Y10T29/49121

Claims Analysis

Total Claims: 12
Claim 1
Independent Claim 75 words
A method of testing a plurality of integrated circuits which are enclosed in packages, wherein the packages are attached to a leadframe and a number of leads which are coupled to each of the integrated circuits extend from each package, the method comprising the steps of: separating the leads from each other and from the leadframe; coupling a tester to the leads; testing the integrated circuits; and separating the packages from the leadframe after testing.
Claim 2
Independent Claim 75 words
A method of testing a plurality of integrated circuits which are enclosed in packages, wherein the packages are attached to a leadframe and a number of leads which are coupled to each of the integrated circuits extend from each package, the method comprising the steps of: separating the leads from each other and from the leadframe; coupling a tester to the leads; testing the integrated circuits; and separating the packages from the leadframe after testing.
Claim 3
Dependent Claim 43 words
The method of claim 1 further comprising the step of bending the leads away from the package after the step of separating the leads from each other and the leadframe; and moving test contacts to the leads in order to perform the coupling.
Claim 4
Dependent Claim 30 words
The method of claim 2 further comprising the step of bending the leads into a predefined shape after testing the integrated circuits and before separating the packages from the leadframe.
Claim 5
Dependent Claim 92 words
A test fixture for testing a plurality of packaged integrated circuits which are attached to a leadframe, wherein each of the integrated circuits has a plurality of leads which are isolated from the leadframe, the test fixture comprising: a membrane test head having a plurality of contacts thereon positioned underneath the plurality of leads; a tester coupled to the test head; a drive means for moving the test head towards and away from the plurality of leads, wherein the membrane test head couples to a plurality of packaged ICs at one time.
Claim 6
Dependent Claim 92 words
A test fixture for testing a plurality of packaged integrated circuits which are attached to a leadframe, wherein each of the integrated circuits has a plurality of leads which are isolated from the leadframe, the test fixture comprising: a membrane test head having a plurality of contacts thereon positioned underneath the plurality of leads; a tester coupled to the test head; a drive means for moving the test head towards and away from the plurality of leads, wherein the membrane test head couples to a plurality of packaged ICs at one time.
Claim 7
Dependent Claim 15 words
The test fixture of claim 4 wherein the plurality of ICs are tested in parallel.
Claim 8
Dependent Claim 24 words
The test fixture of claim 4 wherein the ICs are tested serially by multiplexing the tester to each IC of the plurality of ICs.
Claim 9
Independent Claim 148 words
A method for leadforming and testing a plurality of integrated circuits in individual packages, wherein the packages are attached to a leadframe by tie bars and a number of leads which are coupled to the integrated circuits, the method comprising: cutting the leads and the bars to electrically separate the number of leads from each other and from the leadframe; bending the leads so that a portion of each of the leads extends below the package; contacting the leads with a membrane test head located below the packages, the membrane test head having a number of probe bumps which are coupled to an external tester and which are aligned to the number of leads of the plurality of integrated circuits; an innflatable bladder located below the membrane test head; bending the leads to complete a leadform; and cutting the tie bars to separate the package from the leadframe.
Claim 10
Independent Claim 148 words
A method for leadforming and testing a plurality of integrated circuits in individual packages, wherein the packages are attached to a leadframe by tie bars and a number of leads which are coupled to the integrated circuits, the method comprising: cutting the leads and the bars to electrically separate the number of leads from each other and from the leadframe; bending the leads so that a portion of each of the leads extends below the package; contacting the leads with a membrane test head located below the packages, the membrane test head having a number of probe bumps which are coupled to an external tester and which are aligned to the number of leads of the plurality of integrated circuits; an innflatable bladder located below the membrane test head; bending the leads to complete a leadform; and cutting the tie bars to separate the package from the leadframe.
Claim 11
Dependent Claim 35 words
The method of claim 7 further comprising providing a number of microstrip transmission lines formed on the membrane test head, wherein each microstrip transmission line is coupled to a probe bump and to the tester.
Claim 12
Dependent Claim 28 words
The method of claim 7 further comprising filling the inflatable bladder with gas to move the membrane test head so that the probe bumps couple to the leads.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1994-04-15 1994-10-15 1995-04-16 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1998-04-15 1998-10-15 1999-04-16 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2002-04-15 2002-10-15 2003-04-16 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag