High-speed, adaptive IDDQ measurement
US6342790B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 13, 2000 |
| Grant date | Jan 29, 2002 |
| Priority date | — |
| Expiry date | Apr 13, 2020 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R31/3008
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Test device (DUT) current flow is mirrored through a capacitor. If the mirrored current is switched to bypass the capacitor, the capacitor discharges. Otherwise, the mirrored current charges the capacitor. The charging capacitor's voltage rise time is proportional to the DUT's IDDQ current. Several IDDQ reference values can be derived, each representing quiescent state operation of a defect-free copy of the DUT. An IDDQ test value is derived for each IDDQ reference value. Each test value represents quiescent state operation of the DUT after application of the test vector which produced the corresponding reference value. The reference values are compared to their corresponding test values and a plurality of scaling factors derived. Each scaling factor represents a proportionality between corresponding reference and test values. The DUT is “non-defective” if the scaling factors are equal within a predefined error range . Otherwise, the DUT is “defective”.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.