Circuit delay monitoring apparatus and method
US9432009B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 15, 2013 |
| Grant date | Aug 30, 2016 |
| Priority date | — |
| Expiry date | Jul 31, 2034 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K5/135
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A circuit delay monitoring apparatus has a ring oscillator with a plurality of delay elements, a signal transition being propagated through the delay elements of the ring oscillator, and a plurality N of sampling points being distributed around the ring oscillator. Selection circuitry selects, in dependence on the indication of the current location of the signal transition generated by the fine sampling circuitry, one of the M transition counter circuits whose associated location is greater than said predetermined amount from the current location of the signal transition. Output generation circuitry then generates a count indication for a reference time period dependent on a sampled count value of the transition counter circuit selected by the selection circuitry, the indication of the current location of the signal transition within the ring oscillator, and reference count data relating to the start of the reference time period.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.