Temperature tamper detection circuit and method
US7362248B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 26, 2006 |
| Grant date | Apr 22, 2008 |
| Priority date | — |
| Expiry date | Jun 26, 2026 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01K7/015
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A sensing circuit determines whether an integrated circuit is currently exposed to one of a relatively low or a relatively high temperature. A selection circuit selects a measured voltage across the base-emitter of a bipolar transistor if the sensing circuit indicates that the circuit is exposed to the relatively low temperature or, alternatively, selects a measured delta voltage across the base-emitter of the bipolar transistor if the sensing circuit indicates that the circuit is exposed to the relatively high temperature. A comparator compares the selected measured voltage against a first reference voltage indicative of a too cold temperature condition or compares the selected measured delta voltage against a second reference voltage indicative of a too hot temperature condition. As a result of the comparison, detection may be made as to whether the integrated circuit is currently exposed to a too cold or too hot temperature.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.