US4588945A
Expired / Lapsed
US
⏱️ 0.0 years remaining
High throughput circuit tester and test technique avoiding overdriving damage
Assignee: Agilent Technologies Inc
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Filing: 1983-06-13
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Granted: 1986-05-13
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Expires: 2003-06-13
Abstract
Abstract A method and apparatus are disclosed for reducing the likelihood of damage to digital logic devices under test or located in close electrical proximity to the device under test while attempting to locate faults in circuit assemblies using digital incircuit test techniques.
Inventors
- 👤 William A. Groves
- 👤 Vance R. Harwood
- 👤 Thomas R. Fay
- 👤 Elton C. Bingham
- 👤 Michael A. Teska
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 10:35
CPC Classifications
G; G01; G01R; G01R31/00; G01R31/28; G01R31/317; G01R31/3181; G01R31/319; G01R31/31903; G01R31/31915
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
84 words
An improved method of testing circuits consisting of devices of the type in which test signals are applied directly to each device under test and output signals from each device under test are monitored, wherein the improvement comprises the additional step of introducing, between the application of test signals for each device, a predetermined variable length cool down time interval determined from characteristics of the devices and the circuit sufficient to avoid damage to the circuit due to overheating of devices of the circuit.
Claim 2
Dependent Claim
84 words
An improved method of testing circuits consisting of devices of the type in which test signals are applied directly to each device under test and output signals from each device under test are monitored, wherein the improvement comprises the additional step of introducing, between the application of test signals for each device, a predetermined variable length cool down time interval determined from characteristics of the devices and the circuit sufficient to avoid damage to the circuit due to overheating of devices of the circuit.
Claim 3
Dependent Claim
42 words
A method as in claim 1 wherein the predetermined variable length cool down time interval is determined by the steps of calculating the minimum time duration for each cool down time interval sufficient to avoid damage to any device of the circuit.
Claim 4
Dependent Claim
36 words
A method as in claim 1 wherein the predetermined variable length cool down time interval is introduced before the application of the test signals to the device under test for which the time interval was determined.
Claim 5
Independent Claim
73 words
A method for preventing the overheating of an electronic device under test with initialization test signals during an initializing period or regular test signals during a testing period, the method comprising: counting the number of times the initialization test signals are applied to the electronic device under test, measuring the duration of the testing period and terminating the application of test signals when a predetermined count or a predetermined period has been reached.
Claim 6
Independent Claim
73 words
A method for preventing the overheating of an electronic device under test with initialization test signals during an initializing period or regular test signals during a testing period, the method comprising: counting the number of times the initialization test signals are applied to the electronic device under test, measuring the duration of the testing period and terminating the application of test signals when a predetermined count or a predetermined period has been reached.
Claim 7
Dependent Claim
77 words
A circuit tester for testing circuits consisting of devices, the circuit tester comprising: means for applying test signals to each device under test; means for monitoring signals from each device under test; and means for introducing a predetermined variable length cool down time interval determined from characteristics of the devices and the circuit between the application of test signals for each device sufficient to prevent damage to any of the devices of the circuit due to overheating.
Claim 8
Dependent Claim
77 words
A circuit tester for testing circuits consisting of devices, the circuit tester comprising: means for applying test signals to each device under test; means for monitoring signals from each device under test; and means for introducing a predetermined variable length cool down time interval determined from characteristics of the devices and the circuit between the application of test signals for each device sufficient to prevent damage to any of the devices of the circuit due to overheating.
Claim 9
Dependent Claim
66 words
A circuit tester as in claim 5 further comprising: data flies containing information of circuit topology and safeguard parameters of circuit devices; a damage analyzer responsive to the information in the data files for calculating minimum length cool down time intervals sufficient to prevent overheating damage; and a controller responsive to signals from the damage analyzer to control the length of each cool down time interval.
Claim 10
Dependent Claim
46 words
A circuit tester as in claim 5 wherein the means for introducing the predetermined variable length cool down time interval is operative for introducing the time interval before the application of the test signals to the device under test for which the time interval was determined.
Claim 11
Dependent Claim
24 words
A circuit tester as in claim 7 further comprising means for varying the slope of the test signal applied to the device under test.
References Cited (Backward Citations)
US3870953A
Cited
US4507576A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-05-12 | 1989-11-11 | 1990-05-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-05-12 | 1993-11-11 | 1994-05-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-05-12 | 1997-11-11 | 1998-05-13 | $7700.00 | Window Closed / Lapsed |