Data carrier for the adaptation of a consumption time interval to the power consumption of the data carrier
US6883103B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 30, 2001 |
| Grant date | Apr 19, 2005 |
| Priority date | — |
| Expiry date | Feb 18, 2023 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06K7/0008
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A data carrier that communicates confidential data is configured to mask process-dependent power consumption by using power stored in an internal capacitor. The capacitor is initially charged to the voltage of an external power source, and then decoupled from the external power source. The capacitor provides power to an internal processor, and consequently discharges gradually. At the end of a given time interval, the capacitor is discharged to a fixed voltage, then charged to the supply voltage. In this manner the power consumed by charging of the capacitor is decoupled from the power consumed by the processor. If the capacitor drops below a threshold voltage before processing is completed, the processor is halted. To optimize the available processing time, the time interval before discharging the capacitor to the fixed voltage is dynamically adjusted to reduce the time that the processor is halted.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.