Resistor/capacitor based identification detection
US7631176B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 24, 2006 |
| Grant date | Dec 8, 2009 |
| Priority date | — |
| Expiry date | Jan 7, 2028 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05K2201/09927
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A resistor/capacitor identification detection (RCID) circuit may provide system level identification of hardware (e.g. circuit board ID) through a single pin interface, by identifying up to a specified number of more than two quantized RC time constant states by measuring the discharge and charge times of an external RC circuit coupled to the single pin. The RCID circuit may initiate the discharge followed by a charging of the external RC circuit. The signal developed at the signal pin may be provided to the input of a threshold detector, with the threshold set at a specified percentage of a supply voltage used for operating the RCID circuit. The digitized output of the threshold detector may be used to gate a counter, after having been filtered through an input glitch rejection filter. A resolution of the counter may be determined by a high frequency clock used for clocking the counter. The numeric values of the charge and discharge times may be stored in data registers comprised in the RCID circuit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.